,transcriber's ,notes ,when italics were used in the original book1 the corresponding text has been surrounded by underscores4 ,the oe ligature has been replaced by the letters oe4 ,the ,greek letter lambda has been represented as lambda4 ,some presumed printer's errors have been corrected4 ,these have been listed in a second transcriber's note at the end of the text4 ,,mars ,,and ,,its ,,canals ---------------------------------------- -------------------------------- ,illustration3 ,mars' ,hill ---------------------------------------- -------------------------------- ,,mars ,,and ,,its ,,canals ,,by ,,percival ,,lowell ,,director ,,of ,,the ,,observatory ,,at ,,flagstaff1 ,,arizona2 ,,non-,,resident ,,professor ,,of ,,astronomy ,,at ,,the ,,massachusetts ,,institute ,,of ,,technology2 ,,fellow ,,of ,,the ,,american ,,academy ,,of ,,arts ,,and ,,sciences2 ,,membre ,,de ,,la ,,soci,t ,,astronomique ,,de ,,france2 ,,member ,,of ,,the ,,astronomical ,,and ,,astrophysical ,,society ,,of ,,america2 ,,mitglied ,,der ,,astronomischen ,,gesellschaft2 ,,membre ,,de ,,la ,,soci,t ,,belge ,d',,astronomie2 ,,honorary ,,member ,,of ,,the ,,sociedad ,,astronomica ,,de ,,mexico2 ,,janssen ,,medalist ,,of ,,the ,,soci,t ,,astronomique ,,de ,,france1 #aijd1 ,,for ,,researches ,,on ,,mars2 ,,etc41 ,,etc4 ,,illustrated ,new ,york ,,the ,,macmillan ,,company ,,london3 ,,macmillan ,,co41 ,,ltd4 #aijf ,all rights reserved ,,copyright1 #aijf1 ,,by ,,the ,,macmillan ,,company4 ------- ,set up and electrotyped4 ,published ,december1 #aijf4 ,norwood ,press ,j4 ,s4 ,cushing ,co4--,berwick ,smith ,co4 ,norwood1 ,mass41 ,u4,s4,a4 ---------------------------------------- -------------------------------- ,to ,g4 ,v4 ,,schiaparelli ,,the ,,columbus ,,of ,a ,,new ,,planetary ,,world ,,this ,,investigation ,,upon ,,it ,,is ,,appreciatively ,,inscribed ,,preface ,eleven years have elapsed since the writer's first work on ,mars was published in which were recorded the facts gleaned in his research up to that time and in which was set forth a theory of their explanation4 ,continued work in the interval has confirmed the conclusions there stated2 sometimes in quite unexpected ways4 ,five times during that period ,mars has approached the earth within suitable scanning distance and been subjected to careful and prolonged scrutiny4 ,familiarity with the subject1 improved telescopic means1 and long-continued training have all combined to increased efficiency in the procuring of data and to results which have been proportionate4 ,a mass of new material has thus been collected1--some of it along old lines1 some of it in lines that are themselves new1--and both have led to the same outcome4 ,in addition to thus pushing inquiry into advanced portions of the subject1 study has been spent in investigation of the reality of the phenomena upon which so much is based1 and in testing every theory which has been suggested to account for them4 ,from diplopia to optical interference1 each of these has been examined and found incompatible with the observations4 ,the phenomena are all they have been stated to be1 and more4 ,each step forward in observation has confirmed the genuineness of those that went before4 ,to set forth science in a popular1 that is1 in a generally understandable1 form is as obligatory as to present it in a more technical manner4 ,if men are to benefit by it1 it must be expressed to their comprehension4 ,to do this should be feasible for him who is master of his subject and is both the best test of1 and the best training to1 that post4 ,especially vital is it that the exposition should be done at first hand2 for to describe what a man has himself discovered comes as near as possible to making a reader the co-discoverer of it4 ,not only are thus escaped the mistaken glosses of second-hand knowledge1 but an aroma of actuality1 which cannot be filtered through another mind without sensible evaporation1 clings to the account of the pioneer4 ,nor is it so hard to make any well-grasped matter comprehensible to a man of good general intelligence as is commonly supposed4 ,the whole object of science is to synthesize1 and so simplify2 and did we but know the uttermost of a subject we could make it singularly clear4 ,meanwhile technical phraseology1 useful as shorthand to the cult1 becomes meaningless jargon to the uninitiate and is paraded most by the least profound4 ,but worse still for their employ symbols tend to fictitious understanding4 ,formul are the ansthetics of thought1 not its stimulants2 and to make any one think is far better worth while than cramming him with ill-considered1 and therefore indigestible1 learning4 ,even to the technical student1 a popular book1 if well done1 may yield most valuable results4 ,for nothing in any branch of science is so little known as its articulation1--how the skeleton of it is put together1 and what may be the mode of attachment of its muscles4 ,,contents ,,page ,,preface vii ,,part ,i ,,natural ,,features ,,chapter ,i4 ,,on ,,exploration #c ,,ii4 ,a ,,departure-,,point #ab ,,iii4 ,a ,,bird',s-,,eye ,,view ,,of ,,past ,,martian ,,discovery #bj ,,iv4 ,,the ,,polar ,,caps #cb ,v4 ,,behavior ,,of ,,the ,,polar ,,caps #da ,,vi4 ,,martian ,,polar ,,expeditions #ed ,,vii4 ,,white ,,spots #gc ,,viii4 ,,climate ,,and ,,weather #hb ,,ix4 ,,mountains ,,and ,,cloud #if ,x4 ,,the ,,blue-,,green ,,areas #ajh ,,xi4 ,,vegetation #aai ,,xii4 ,,terraqueousness ,,and ,,terrestriality #abh ,,xiii4 ,,the ,,reddish-,,ochre ,,tracts #adh ,,xiv4 ,,summary #aei ,,part ,,ii ,,non-,,natural ,,features ,,xv4 ,,the ,,canals #agc ,,xvi4 ,,their ,,system #ahd ,,xvii4 ,,gemination ,,of ,,the ,,canals #aib ,i4 ,,the ,,diplopic ,,theory #aif ,,ii4 ,,the ,,interference ,,theory #bja ,,iii4 ,,the ,,illusion ,,theory #bjb ,,xviii4 ,,the ,,double ,,canals #bjd ,,xix4 ,,canals ,,in ,,the ,,dark ,,regions #bdc ,,xx4 ,,oases #bdi ,,xxi4 ,,carets ,,on ,,the ,,borders ,,of ,,the ,,great ,,diaphragm #bfe ,,xxii4 ,,the ,,canals ,,photographed #bga ,,part ,,iii ,,the ,,canals ,,in ,,action ,,xxiii4 ,,canals3 ,,kinematic #bha ,,xxiv4 ,,canal ,,development ,,individually ,,instanced #cjd ,,xxv4 ,,hibernation ,,of ,,the ,,canals #cac ,,xxvi4 ,,arctic ,,canals ,,and ,,polar ,,rifts #cbe ,,xxvii4 ,,oases3 ,,kinematic #ccj ,,part ,,iv ,,explanation ,,xxviii4 ,,constitution ,,of ,,the ,,canals ,,and ,,oases #ccg ,,xxix4 ,,life #cdh ,,xxx4 ,,evidence #cfj ,,xxxi4 ,,the ,,husbanding ,,of ,,water #cff ,,xxxii4 ,,conclusion #cgf ,,index #che ,,list ,,of ,,illustrations ,,plates ,,mars' ,,hill ,frontispiece ,,page ,,the ,,hermitage #h ,,the ,,san ,,francisco ,,peaks #ah ,,martian ,,maps ,,by3 ,i4 ,,beer ,,and ,,maedler4 #ahdj #bf ,,ii4 ,,kaiser4 #ahfd #bf ,,iii4 ,,flammarion 7,r,,sum74 #ahgf #bg ,,iv4 ,,green4 #ahgg #bg ,v4 ,,schiaparelli4 #ahgg #bh ,,vi4 ,,schiaparelli4 #ahgi #bh ,,vii4 ,,schiaparelli4 #ahha #bi ,,viii4 ,,schiaparelli4 #ahhd #bi ,,ix4 ,,lowell4 #ahid #cj ,x4 ,,lowell4 #ahif #cj ,,xi4 ,,lowell4 #aija #ca ,,xii4 ,,lowell4 #aije #ca ,,south ,,polar ,,cap4 #aije #db ,,north ,,polar ,,cap4 #aije #dd ,,mare ,,erythraeum1 ,,martian ,,date1 ,,december #cj #abj ,,mare ,,erythraeum1 ,,martian ,,date1 ,,january #af #abb ,,mare ,,erythraeum1 ,,martian ,,date1 ,,february #a #abd ,,mare ,,erythraeum1 ,,martian ,,date1 ,,february #ba #abf ,,mars1 ,,on ,,mercator',s ,,projection #chd ,,cuts ,,appearing ,,in ,,text ,,south ,,polar ,,cap ,,in ,,winter #ef ,,hellas ,,in ,,winter #ei ,,white ,,south ,,of ,,nectar ,,and ,,solis ,,lacus #ei ,,northern ,,cap ,,hooded ,,with ,,vapor #fd ,,northern ,,cap ,,unmasked #fe ,,deposition ,,of ,,frost #gj ,,first ,,northern ,,snow #gb ,,white ,,in ,,elysium #ge ,,white ,,in ,,the ,,pons ,,hectoris #gh ,,projection ,,on ,,terminator #aja ,,lines ,,in ,,dark ,,area #aag ,,map ,,of ,,north ,,america ,,at ,,the ,,close ,,of ,,arch,,an ,,time #acb ,,north ,,america ,,at ,,opening ,,of ,,upper ,,silurian ,,period #acd ,,map ,,of ,,north ,,america ,,after ,,the ,,appalachian ,,revolution #ace ,,north ,,america ,,in ,,the ,,cretaceous ,,period #acf ,,north ,,america1 ,,showing ,,the ,,parts ,,under ,,water ,,in ,,the ,,tertiary ,,era #acg ,,earth',s ,,desert ,,areas1 ,,western ,,hemisphere #aef ,,earth',s ,,desert ,,areas1 ,,eastern ,,hemisphere #aeg ,,showing ,,the ,,eumenides-,,orcus #ahc ,,martian ,,doubles #bjf ,,martian ,,doubles #bjg ,,mouths ,,of ,,euphrates ,,and ,,phison4 ,,june1 #aijc #bai ,,peculiar ,,development ,,of ,,the ,,ganges #bbh ,,djihoun1 ,,the ,,narrowest ,,double #bbi ,,the ,,sabaeus ,,sinus1 ,,embouchure ,,for ,,the ,,double ,,hiddekel ,,and ,,gihon #bcb ,,the ,,propontis1 #aije #bdg ,,fons ,,immortalis1 ,,june #ai #bed ,,utopia ,,regio4 #aijc #bef ,,ascraeus ,,lucus ,,and ,,gigas4 ,,march #b1 #aijc #beh ,,peculiar ,,association ,,of ,,the ,,luci ,,ismenii ,,with ,,double ,,canals #bfj ,,lucus ,,ismenius4 ,,march1 #aijc #bfb ,,showing ,,seasonal ,,change4 ,i #bhe ,,showing ,,seasonal ,,change4 ,,ii #bhe ,,mean ,,canal ,,cartouches #bih ,,showing ,,development ,,of ,,the ,,brontes3 ,i4 ,,february #be #cjf ,,ii4 ,,march #cj #cjg ,,iii4 ,,april #c #cjg ,,iv4 ,,may #d #cjh ,v4 ,,may #g #cjh ,,vi4 ,,july #ah #cji ,,cartouches ,,of ,,the ,,brontes #caa ,,amenthes ,,alone ,,in ,,february #cai ,,amenthes ,,feebler ,,and ,,still ,,alone ,,in ,,march #cai ,,appearance ,,of ,,thoth ,,with ,,triton ,,and ,,curved ,,nepenthes4 ,,amenthes ,,vanished1 ,,april #bj #cbj ,,advent ,,of ,,the ,,lucus ,,moeris4 ,,may #bi #cba ,,amenthes ,,with ,,thoth-,,nepenthes4 ,,july #cbb ,,cartouches ,,of ,,amenthes1 ,,thoth1 ,,and ,,their ,,combination #cbc ,,phenology ,,curves--,,earth #cdb ,,phenology ,,curves--,,mars #cdc ,,part ,i ,,natural ,,features ,,mars ,,and ,,its ,,canals ,,chapter ,i ,,on ,,exploration ,from time immemorial travel and discovery have called with strange insistence to him who1 wondering on the world1 felt adventure in his veins4 ,the leaving familiar sights and faces to push forth into the unknown has with magnetic force drawn the bold to great endeavor and fired the thought of those who stayed at home4 ,spur to enterprise since man first was1 this spirit has urged him over the habitable globe4 ,linked in part to mere matter of support it led the more daring of the ,aryans to quit the shade of their beech trees1 reposeful as that umbrage may have been1 and wander into ,central ,asia1 so to perplex philologists into believing them to have originated there2 it lured ,columbus across the waste of waters and caused his son to have carved upon his tomb that ringing couplet of which the simple grandeur still stirs the blood3-- ,,castilla ,y ,,leon ,,nuevo ,,mondo ,,di ,,colon2 7,to ,castile and ,leon beyond the wave ,another world ,columbus gave27 it drove the early voyagers into the heart of the vast wilderness1 there to endure all hardship so that they might come where their kind had never stood before2 and now it points man to the pole4 ,something of the selfsame spirit finds a farther field today outside the confines of our traversable earth4 ,science which has caused the world to shrink and dwindle has been no less busy bringing near what in the past seemed inaccessibly remote4 ,beyond our earth man's penetration has found it possible to pierce1 and in its widening circle of research has latterly been made aware of another world of strange enticement across the depths of space4 ,planetary distances1 not mundane ones1 are here concerned1 and the globe to be explored1 though akin to1 is yet very different from1 our own4 ,this other world is the planet ,mars4 ,sundered from us by the ocean of ether1 a fellow-member of our own community of matter there makes its circuit of the sun upon whose face features show which stamp it as cognate to that on which we live4 ,in spite of the millions of miles of intervening matterless void1 upon it markings can be made out that distantly resemble our earth's topography and grow increasingly suggestive as vision shapes them better2 and yet among the seemingly familiar reveal aspects which are completely strange4 ,but more than this3 over the face of it sweep changes that show it to be not a dead but a living world1 like ours in this1 and luring curiosity by details unknown here to further exploration of its unfamiliar ground4 ,to observe ,mars is to embark upon this enterprise2 not in body but in mind4 ,though parted by a gulf more impassable than any sea1 the telescope lets us traverse what otherwise had been barred and lands us at last above the shores we went forth to seek4 ,real the journey is1 though incorporeal in kind4 ,since the seeing strange sights is the essence of all far wanderings1 it is as truly travel so the eye arrive as if the body kept it company4 ,indeed1 sight is our only far viatic sense4 ,touch and taste both hang on contact1 smell stands indebted to the near and even hearing waits on ponderable matter where sound soon dissipates away2 only sight soars untrammeled of the grosser adjunct of the flesh to penetrate what were otherwise unfathomable space4 ,what the voyager thus finds himself envisaging shares by that very fact in the expansion of the sense that brought him there4 ,no longer tied by means of transport to seas his sails may compass or lands his feet may tread1 the traveler reaches a goal removed in kind from his own habitat4 ,he proves to have adventured1 not into unknown parts of a known world1 but into one new to him in its entirety4 ,in extent alone he surveys what dwarfs the explorer's conquests on ,earth4 ,but size is the least of the surprises there in store for him4 ,what confronts his gaze finds commonly no counterpart on ,earth4 ,his previous knowledge stands him in scant stead4 ,for he faces what is so removed from every day experience that analogy no longer offers itself with safety as a guide4 ,he must build up new conceptions from fresh data and slowly proceed to deduce the meaning they may contain4 ,science alone can help him to interpretation of what he finds1 and above all must he wean himself from human prejudice and earthbound limitation4 ,for he deals here with ultramundane things4 ,with just enough of cosmogony in common to make decipherment not despairable this world is yet so different from the one he personally knows as to whet curiosity at every turn4 ,he is permitted to perceive what piques inquiry and by patient adding of point to point promises at last a rational result4 ,like mundane exploration1 it is arduous too2 ad astra per aspera is here literally true4 ,for it is a journey not devoid of hardship and discomfort by the way4 ,its starting-point preludes as much4 ,to get conditions proper for his work the explorer must forego the haunts of men and even those terrestrial spots found by them most habitable4 ,astronomy now demands bodily abstraction of its devotee4 ,its deities are gods that veil themselves amid man-crowded marts and impose withdrawal and seclusion for the prosecution of their cult as much as any worshiped for other reason in more primeval times4 ,to see into the beyond requires purity2 in the medium now as formerly in the man4 ,as little air as may be and that only of the best is obligatory to his enterprise1 and the securing it makes him perforce a hermit from his kind4 ,he must abandon cities and forego plains4 ,only in places raised above and aloof from men can he profitably pursue his search1 places where nature never meant him to dwell and admonishes him of the fact by sundry hints of a more or less distressing character4 ,to stand a mile and a half nearer the stars is not to stand immune4 ,thus it comes about that today besides its temples erected in cities1 monasteries in the wilds are being dedicated to astronomy as in the past to faith2 monasteries made to commune with its spirit1 as temples are to communicate the letter of its law4 ,pioneers in such profession1 those already in existence are but the precursors of many yet to come as science shall more and more recognize their need4 ,advance in knowledge demands what they alone can give4 ,primitive1 too1 they must be as befits the still austere sincerity of a cult1 in which the simplest structures are found to be the best4 ,still the very wildness of the life their devotee is forced to lead has in it a certain fittingness for his post in its primeval detachment from the too earthbound1 in concept as in circumstance4 ,withdrawn from contact with his kind1 he is by that much raised above human prejudice and limitation4 ,to sally forth into the untrod wilderness in the cold and dark of a winter's small hours of the morning1 with the snow feet deep upon the ground and the frosty stars for mute companionship1 is almost to forget one's self a man for the solemn awe of one's surroundings4 ,fitting portal to communion with another world1 it is through such avenue one enters on his quest where the common and familiar no longer jostle the unknown and the strange4 ,nor is the stillness of the stars invaded when some long unearthly howl1 like the wail of a lost soul1 breaks the slumber of the mesa forest1 marking the prowling presence of a stray coyote4 ,gone as it came1 it dies in the distance on the air that gave it birth2 and the gloom of the pines swallows up one's vain peering after something palpable1 their tops alone decipherable in dark silhouette against the sky4 ,from amid surroundings that for their height and their intenancy fringe the absolute silence of space the observer must set forth who purposes to cross it to another planetary world4 ,illustration3 ,the ,hermitage ,but the isolation of his journey is not always so forbidding4 ,his coming back is no less girt with grandeur of a different though equally detached a kind4 ,even before the stars begin to dim in warning to him to return1 a faint suffusion as of half-suspected light creeps into the border of the eastern sky4 ,against it1 along the far pine-clad horizon1 mesa after mesa in shaggy lines of sentineling earth1 stands forth dark marshaled in the gloom1 informed with prescience of what is soon to come4 ,imperceptibly the pallor grows1 blanching the face of night and one by one extinguishing the stars4 ,slowly then it takes on color1 tingeing ever so faintly to a flush that swells and deepens as the minutes pass4 ,one had said the sky lay dreaming of the sun in pale imagery at first that gathers force and feeling till the dreamer turns thus rosy red in slumbering supposition of reality4 ,then the blush dies out4 ,the crimson fades to pink1 the pink to ashes4 ,the stars have disappeared and yet it is not day4 ,it is the supreme moment of the dawn1 the hush with which the ,earth awaits its full awakening4 ,for now again the color gathers in the east1 not with the impalpable suffusion it had before but nearer and more vivid4 ,no longer reflectively remote1 rays imminent of the sun strike the upper air1 the most adventurously refrangible turning the underside of a few stray clouds into flame-hued bars of glowing metal4 ,they burn thus in the silent east first red1 then orange1 and then gold1 each spectral tint in prismatic revelation coming to join the next till in a sudden blinding burst of splendor the solar disk tops the horizon's rim4 ,not less impressive is the journey when the afternoon watch has replaced the morning vigil by the drawing of the planet nearer to the sun4 ,lost in the brilliance of the dazzling sky1 the planet lies hid from the senses' search4 ,the quest were hopeless did not the mind guide the telescope to its goal4 ,to theory alone is it visible still1 and so to its predicted place the observer sets his circles1 and punctual to the prophecy the planet swings into the field of view4 ,one must be dulled by long routine to such mastery of mind not to have the act itself clothe with a sense of charmed withdrawal the object of his quest4 ,so much and more there are of traveler's glimpses by the way1 compensation that offsets the frequent discomfort1 and even balking of his purpose by inopportune cloud4 ,for the best of places is not perfect1 and a storm will sometimes rob him of a region he wished to see4 ,he must learn to wait upon his opportunities and then no less to wait for mankind's acceptance of his results2 for in common with most explorers he will encounter on his return that final penalty of penetration1 the certainty at first of being disbelieved4 ,in such respect he will be even worse off than were the other world discoverers of the fifteenth and sixteenth centuries4 ,for they at least could offer material proof of things that they had seen4 ,dumb ,indians and gold spoke more convincingly than the lips of the great navigators4 ,to astronomy1 too1 that other world was due4 ,without a knowledge of the earth's shape and size got from ,francisco of ,pisa1 ,columbus had never adventured himself upon the deep4 ,but more than this1 an astronomer it was1 in the person of ,americus ,vespucius1 who first discovered the new world1 by recognizing it as such2 ,columbus never dreaming he had lighted upon a world that was new4 ,nor does it impair one jot or tittle of his glory that he knew it not4 ,nothing can deprive him of the imperishable fame of launching forth into the void in hope of a beyond1 though he found not what he sought but something stranger still4 ,so1 curiously1 has it been with the trans-etherian4 ,to ,schiaparelli the republic of science owes a new and vast domain4 ,his genius first detected those strange new markings on the ,martian disk which have proved the portal to all that has since been seen1 and his courage in the face of universal condemnation led to exploration of them4 ,he made there voyage after voyage1 much as ,columbus did on ,earth1 with even less of recognition from home4 ,as with ,columbus1 too1 the full import of his great discovery lay hid even to him and only by discoveries since is gradually resulting in recognition of another sentient world4 ,,chapter ,,ii ,a ,,departure-,,point ,as the character of the travel is distinctive1 so the outcome of the voyage is unique4 ,if he choose his departure-point aright1 the observer will be vouchsafed an experience without parallel on ,earth4 ,to select this setting-out station is the first step in the journey upon which everything depends4 ,for it is essential to visual arrival that a departure-point be taken where definition is at its best4 ,now1 so far as our present knowledge goes1 the conditions most conducive to good seeing turn out to lie in one or other of the two great desert belts that girdle the globe4 ,many of us are unaware of the existence of such belts and yet they are among the most striking features of physical geography4 ,could we get off our globe and view it from without we should mark two sash-like bands of country1 to the poleward side of either tropic1 where the surface itself lay patently exposed4 ,unclothed of verdure themselves they would stand forth doubly clear by contrast4 ,for elsewhere cloud would hide to a greater or less extent the actual configuration of the ,earth's topography to an observer scanning it from space4 ,one of these sash-like belts of desert runs through southern ,california1 ,arizona1 ,new ,mexico1 the ,sahara1 ,arabia ,petra and the ,desert of ,gobi2 the other traverses ,peru1 the ,south ,african veldt1 and ,western ,australia4 ,they are desert because in them rain is rare2 and even clouds seldom form4 ,in a twofold way they conduce to astronomic ends4 ,absence of rain makes primarily for clear skies and secondarily for steady air2 and the one of these conditions is no less vital to sight than the other4 ,water vapor is a great upsetter of atmospheric equilibrium and commotion in the air the spoiler of definition4 ,thus from the cloudlessness of their skies man finds in them most chance of uninterrupted communion with the stars1 while by suitably choosing his spot he here obtains as well that prime desideratum for planetary work1 as near a heavenly equanimity in the air currents over his head as is practically possible4 ,from the fact that these regions are desert they are less frequented of man1 and the observer is thus perforce isolated by the nature of the case1 the regions best adapted to mankind being the least suited to astronomic observations4 ,in addition to what nature has thus done in the matter1 humanity has further differentiated the two classes of sights by processes of its own contriving4 ,not only is civilized man actively engaged in defacing such part of the ,earth's surface as he comes in contact with1 he is equally busy blotting out his sky4 ,in the latter uncommendable pursuit he has in the last quarter of a century made surprising progress4 ,with a success only too undesirable his habitat has gradually become canopied by a welkin of his own fashioning1 which has rendered it largely unfit for the more delicate kinds of astronomic work4 ,smoke from multiplying factories by rising into the air and forming the nucleus about which cloud collects has joined with electric lighting to help put out the stars4 ,these concomitants of advancing civilization have succeeded above the dreams of the most earth-centred in shutting off sight of the beyond so that today few city-bred children have any conception of the glories of the heavens which made of the ,chaldean shepherds astronomers in spite of themselves4 ,the old world and the new are alike affected by such obliteration4 ,long ago ,london took the lead with fogs proverbial wholly due to smoke1 fine particles of solid matter in suspension making these points of condensation about which water vapor gathers to form cloud4 ,with the increase of smoke-emitting chimneys over the world other centres of population have followed suit till today ,europe and eastern ,north ,america vie with each other as to which sky shall be the most obliterate4 ,even when the obscuration is not patent to the layman it is evident to the meteorologist or astronomer4 ,by a certain dimming of the blue1 smoke or dust reveals its presence high up aloft as telltalely as if the thing itself were visible4 ,some time since the writer had occasion to traverse ,germany in summer from ,gttingen to ,cologne and in so doing was impressed by a cloudiness of the sky he felt sure had not existed when he knew it as a boy4 ,for the change was too startling and extensive to be wholly laid to the score of the brighter remembrances of youth4 ,on reaching ,cologne he mentioned his suspicion to ,klein1 only to find his own inference corroborated2 observations made twenty years ago being impracticable today4 ,two years later in ,milan ,celoria told the same story1 the study of ,mars having ceased to be possible there for like cause4 ,factory smoke and electric lights had combined to veil the planet at about the time ,schiaparelli gave up his observations because of failing sight4 ,with a certain poetic fitness the sky had itself been blotted just at the time the master's eye had dimmed4 ,america is not behind in this race for sky extinction4 ,in the neighborhood of its great cities and spreading into the country round about the heavens have ceased to be favorable to research4 ,not till we pass beyond the ,missouri do the stars shine out as they shone before the white man came4 ,few astronomers even fully appreciate how much this means1 so used does man get to slowly changing conditions4 ,it amounts1 indeed1 between ,washington and ,arizona to a whole magnitude in the stars which may be seen4 ,at the ,naval ,observatory of the former sixty-four stars were mapped in a region where with a slightly smaller glass one hundred and seventy-two were charted at ,flagstaff4 ,besides their immediate use as observing stations these desert belts possess mediate interest on their own account in a branch of the very study their cloudlessness helps to promote1 the branch here considered1 the study of the planet ,mars4 ,they help explain what they permit to be visible4 ,for in the physical history of the ,earth's development they are among the latest phenomena and mark the beginning of that stage of world evolution into which ,mars is already well advanced4 ,they are symptomatic of the passing of a terraqueous globe into a purely terrestrial one4 ,desertism1 the state into which every planetary body must eventually come and for which1 therefore1 it becomes necessary to coin a word1 has there made its first appearance upon the ,earth4 ,standing as it does for the approach of age in planetary existence1 it may be likened to the first gray hairs in man4 ,or better still it corresponds to early autumnal frost in the passage of the seasons4 ,for the beginning to age in a planet means not decrepitude in its inhabitants but the very maturing of this its fruit4 ,evolution of mind in its denizens continues long after desolation in their habitat has set in4 ,indeed1 advance in brain-power seriously develops only when material conditions cease to be bodily propitious and the loss of corporeal facilities renders its acquisition necessary to life4 ,the resemblance1 distant but distinctive1 of the climatic conditions necessary on earth for the best scanning of ,mars with those which prove to be actually existent on that other world has a bearing on the subject worth considerable attention4 ,it helps directly to an understanding and interpretation of the ,martian state of things4 ,though partial only1 the features and traits of our arid zones are sufficiently like what prevails on ,mars to make them in some sort exponent of physical conditions and action there4 ,much that is hard of appreciation in a low1 humid land shows itself an everyday possibility in a high and dry one4 ,the terrible necessity of water to all forms of life1 animal or vegetal1 so that in the simple thought of the aborigines rain is the only god worth great propitiation upon the due observance of which everything depends1 brings to one a deeper realization of what is really vital and what but accessory at best4 ,one begins to conceive what must be the controlling principle of a world where water is only with difficulty to be had1 and rain unknown4 ,but in addition to the fundamental importance of water1 the relative irrelevancy of some other conditions usually deemed indispensable to organic existence there find illustration too4 ,on the high plateau of northern ,arizona and on the still higher volcanic cones that rise from them as a base into now disintegrating peaks1 the thin cold air proves no bar to life4 ,to the fauna there air is a very secondary consideration to water1 and because the latter is scarce in the lowlands and more abundant higher up1 animals ascend after it1 making their home at unusual elevations with no discomfort to themselves4 ,deer range to heights where the barometric pressure is but three fifths that of their generic habitat4 ,bear do the like1 the brown bear of northern ,american sea-level being here met with two miles above it4 ,nor is either animal a depauperate form4 ,man himself contrives to live in comfort and propagate his kind where at first he finds it hard to breathe4 ,nor are these valiant exceptions2 as ,merriam has ably shown in his account of the ,san ,francisco peak region for the ,smithsonian ,institution--a most interesting report1 by the way--the other animals are equally adaptive to the zones of more northern latitudes on the ,american continent1 zones paralleled in their flora and fauna by the zones of altitude up this peak4 ,all which shows that paucity of air is nothing like the barrier to life we ordinarily suppose and is not for an instant to be compared with dearth of water4 ,if in a comparatively short time an animal or plant accustomed to thirty inches of barometric pressure can contrive to subsist sensibly unchanged at eighteen1 it would be rash to set limits to what time may not do4 ,and this the more for another instructive fact discovered in this region by ,merriam3 that the existence of a species was determined not by the mean temperature of its habitat but by the maximum temperature during the time of procreation4 ,a short warm season in summer alone decides whether the species shall survive and flourish2 that it has afterward to hibernate for six months at a time does not in the least negative the result4 ,illustration3 ,the ,san ,francisco ,peaks ,that the point of departure should thus prove of twofold importance1 speeding the observer on his journey and furnishing him with a vade mecum on arrival1 is as curious as opportune4 ,without such furtherance1 to the bodily eye on the one hand and the mind's eye on the other1 the voyage were less conclusive in advent and less satisfactory in attent4 ,,chapter ,,iii ,a ,,bird',s-,,eye ,,view ,,of ,,past ,,martian ,,discovery ,with ,mars discovery has from the start waited on apparent disk4 ,to this end every optical advance has contributed from the time of ,galileo's opera-glass to the present day4 ,for apparent distance stands determined by the size of the eye4 ,but although it is the telescopic eye that has increased1 not the distance that has diminished1 the effect has been kin to being carried nearer the planet and so to a scanning of its disk with constantly increasing particularity4 ,mankind has to all intents and purposes been journeying ,marsward through the years4 ,any historic account of the planet1 therefore1 becomes a chronicle of seeming bodily approach4 ,perhaps no vivider way of making this evident and at the same time no better preface to the present work could be devised than by putting before the eye in orderly succession the maps made of ,mars by the leading areographers of their day1 since the planet first began to be charted sixty-five years ago4 ,the procedure is as much as possible like standing at the telescope and seeing the phenomena steadily disclose4 ,seen thus in order the facts speak for themselves4 ,they show that from first to last no doubt concerning what was seen existed in the minds of those competent to judge by systematic study of the planet at first hand1 and furthermore1 from their mutual corroboration1 that this confidence was well placed4 ,for1 far from there being any conflict of authorities in the case1 those entitled to an opinion in the matter prove singularly at one4 ,beginning with ,maedler in #ahdj the gallery of such portraitures of the planet comprises those by ,kaiser1 ,green and ,schiaparelli1 continued since ,schiaparelli's time by the earlier ones of the present writer4 ,to this list has been added one by ,flammarion1 which though not solely from his own work gives so just a representation of what was known at the date1 #ahgf1 as to merit inclusion4 ,the remarkable drawings of ,dawes and the excellent ones of ,lockyer in #ahfb-ahfd were never combined into maps by the observers1 and though the former's were so synthesized by ,proctor in #ahfg1 the result was conformed to what ,proctor thought ought to be and so is not really a transcript of the drawings themselves4 ,each of the maps presented marked in its day the point areography had reached2 and each tells its own story better than any amount of text4 ,they are all made upon ,mercator's projection and omit in consequence the circumpolar regions4 ,the later ones give1 too1 only so much of the surface as was shown at the opposition they record1 for ,mars1 being tipped now one way1 now another1 regards the earth differently according to its orbital position4 ,in comparing them1 therefore1 the equator must be taken for medial line4 ,mercator's projection has been the customary one for portraying ,mars except for such oppositions as chiefly disclose the arctic pole4 ,and this1 too1 with a certain poetic fitness4 ,for it comes by right of priority to delineation of a new world2 seeing that ,mercator was the first to represent in a map the mundane new world in its entirety1 by the rather important addition of ,north ,america to the southern continent already known1 and to give the whole the title ,america with #8,ame' at the top of the map and #8rica' at the bottom4 ,in looking at the maps it is to be remembered that they are what we should call upside down1 south standing at the top and north at the bottom4 ,inverted they show because this is the way the telescopic observer always sees the planet4 ,the disk would seem unnatural to astronomers were it duly righted4 ,just the same do men in the southern hemisphere look at our own ,earth topsy-turvy according to our view1 the ,sun being to the north of them and the cold to the south4 ,certain landmarks distinguishable in all the maps may serve for specific introduction4 ,the ,v-shaped marking on the equator pointing to the north is the ,syrtis ,major1 the first marking ever made out upon the planet and drawn by the great ,huyghens in #afei4 ,the isolated oval patch in latitude #bf south is the ,solis ,lacus1 the pupil of the eye of ,mars2 while the forked bay on the equator1 discovered by ,dawes1 is the ,sabaeus ,sinus1 the dividing tongue of which1 the ,fastigium ,aryn1 has been taken for the origin of longitudes on ,mars4 ,twelve maps go to make the series4 ,they are as follows3-- ,,maker ,,date ,i4 ,map of ,beer and ,maedler #ahdj ,,ii4 ,map of ,kaiser #ahfd ,,iii4 ,map of ,flammarion 7,rsum7 #ahgf ,,iv4 ,map of ,green #ahgg ,v4 ,map of ,schiaparelli #ahgg ,,vi4 ,map of ,schiaparelli #ahgi ,,vii4 ,map of ,schiaparelli #ahha ,,viii4 ,map of ,schiaparelli #ahhd ,,ix4 ,map of ,lowell #ahid ,x4 ,map of ,lowell #ahif ,,xi4 ,map of ,lowell #aija ,,xii4 ,map of ,lowell #aije ,if these maps be carefully compared they will be found quite remarkably confirmatory each of its predecessor4 ,to no one will their inter-resemblance seem more salient than to draughtsmen themselves4 ,for none know better how surprisingly1 even when two men have the same thing under their very noses to copy1 their two versions will differ4 ,judgment of position and of relative size is one cause of variation2 focusing of the attention on different details another4 ,what slight discrepancies affect the maps are traceable to these two human imperfections4 ,maps ,,iv and ,v make a case in point3 it was to his new-found canals that ,schiaparelli gave heed to the neglect of a due toning of his map2 while ,green1 less keen-eyed but more artistic1 missed the delicate canaliform detail to make a speaking portraiture of the whole4 ,amid the remarkable continuity of progression here shown1 in which each map will be seen to be at once a review and an advance1 we may1 nevertheless1 distinguish three stages in the perception of the phenomena4 ,thus we may mark3-- ,i4 ,a period of recognition of larger markings only2 #ahdj-ahgg ,,ii4 ,a period of detection of canals intersecting the bright regions or lands2 #ahgg-ahib ,,iii4 ,a period of detection of canals traversing the #8seas' and of oases scattered over the surface2 #ahib-aije ,each period is here represented by four charts2 and each expresses the result of a more minute and intimate acquaintance with the disk than was possible to the one that went before4 ,to realize1 however1 how accurate each was according to his lights it is only necessary to have the seeing grow steadily better some evening as one observes4 ,he will find himself recapitulating in his own person the course taken by discovery for all those who went before1 and in the lapse of an hour live through the observational experience of sixty years2 in much the same way that the embryological growth of an individual repeats the development historically of the race4 ,two verses of ,ovid1 which the poet puts into the mouth of ,pythagoras1 outline with something like prophetic utterance the special discoveries which mark the three periods apart4 ,ovid makes ,pythagoras say of the then world3-- ,vidi ego1 quod fuerat quondam solidissima tellus ,esse fretum2 vidi factas ex aequore terras2 --,,ovid1 ,metamorphoses ,,xv1 #bfb4 7,where once was solid ground ,i've seen a strait2 ,lands ,i've seen made from out the sea47 ,true as the verses are of ,earth1 the poet could not have penned them otherwise had he meant to record the course of astronomic detection on ,mars4 ,for they sound like a presentiment of the facts4 ,a surface thought at first to be part land1 part water2 the land next seen to be seamed with straits2 and lastly the sea made out to be land4 ,such is the history of the subject1 and words could not have summed it more succinctly4 8,vidi ego1 quod fuerat quondam solidissima tellus esse fretum0 rings like ,schiaparelli's own announcement of the discovery of the #8canals4' ,indeed1 ,i venture to believe he would have made it had he chanced to recall the verse4 ,so 8vidi factas ex aequore terras0 tells what has since been learned of the character of the seas4 ,of the three periods the first was that of the main or fundamental markings only4 ,it came in with ,beer and ,maedler1 the inaugurators of areography4 ,that they planned and executed their survey with but a four-inch glass shows that there is always room for genius at the top of any profession and that instruments are not for everything in its instrumentality4 ,up to their day the reality of the planet's features had been questioned by some people in spite of having been certainly seen and drawn by ,huyghens and others4 ,beer and ,maedler's labors proved them permanent facts beyond the possibility of dispute4 ,the second period was the period of the discovery of the now famous canals1--a new era in the study of ,mars opened by ,schiaparelli in #ahgg 7,map ,v74 ,unsuspicious of what he was to stumble on1 he seized the then favorable opposition to make1 as he put it1 a geodetic survey of the planet's surface4 ,he hoped this undertaking feasible to the accuracy of micrometric measurement4 ,his hopes did not belie him4 ,he found that it was possible to measure his positions with sufficient exactness to make a skeleton map on which to embody the markings in detail--and thus to give his map vertebrate support4 ,but in the course of his work he became aware of hitherto unrecognized ligaments connecting the seas with one another4 ,instead of displaying a broad unity of face the bright areas appeared to be but groundwork for streaks4 ,the streaks traversed them in all directions1 tesselating the continents into a tilework of islands4 ,such mosaic was not only new1 but the fashion of the thing was of a new order or kind4 ,straits1 however1 ,schiaparelli considered them and gave them the name canali1 or channels4 ,how unfamiliar and seemingly impossible the new detail was is best evidenced by the prompt and unanimous disbelief with which it was met4 ,illustration3 ,map ,i4 ,beer and ,maedler1 #ahdj4 ,illustration3 ,map ,,ii4 ,kaiser1 #ahfd4 7,from ,flammarion's ,mars47 ,illustration3 ,map ,,iii4 ,rsum by ,flammarion1 #ahgf4 7,from ,flammarion's ,mars47 ,illustration3 ,map ,,iv4 ,green1 #ahgg4 7,from ,flammarion's ,mars47 ,unmoved by the universal scepticism which rewarded what was to prove an epoch-making discovery1 ,schiaparelli went on1 in the judgment of his critics1 from bad to worse--for in #ahgi 7,map ,,vi7 he took up again his scrutiny of the planet to the detecting of yet more particularity4 ,he re-observed most of his old canals and discovered half as many more2 and as his map shows he perceived an increased regularity in his lines4 ,in #ahha-ahhb 7,map ,,vii7 he attacked the planet again and with results yet further out of the common4 ,his lines were still there with more beside4 ,if they had looked strange before1 they now appeared positively unnatural4 ,not content with a regularity which seemed to the sceptics to preclude their being facts1 he must needs see them now in duplicate4 ,to the eyes of disbelief this was the crowning stroke of factitiousness4 ,in consequence no end of adverse criticism was heaped upon his observations by those who could not see4 ,but curiously enough1--what did not attract attention1--the blindness of the critics was as much mental as bodily4 ,for they failed to perceive that the very unnaturalness which seemed to them to discredit his observations really proved their genuineness4 ,his discoveries were so amazing that any change in strangeness simply went to confirm the universal scepticism and clouded logic4 ,yet properly viewed1 a pregnant deduction stands forth quite clearly on a study of the maps4 ,illustration3 ,map ,v4 ,schiaparelli1 #ahgg4 7,from ,schiaparelli's ,memoria47 ,illustration3 ,map ,,vi4 ,schiaparelli1 #ahgi4 7,from ,schiaparelli's ,memoria47 ,illustration3 ,map ,,vii4 ,schiaparelli1 #ahha4 7,from ,schiaparelli's ,memoria47 ,illustration3 ,map ,,viii4 ,schiaparelli1 #ahhd4 7,from ,schiaparelli's ,memoria47 ,on comparing maps ,v1 ,,vi and ,,vii an eye duly directed is struck by a difference in the aspect of the lines4 ,in his first map the #8canals' are depicted simply as narrow winding streaks1 hardly even roughly regular and by no means such departures from the plausible as to lie without the communicatory pale4 ,indeed1 to a modern reader prepared beforehand for geometric construction they will probably appear no #8canals' at all4 ,certainly the price of acceptance was not a large one to pay4 ,but like that of the ,sibylline ,books it increased with putting off4 ,what he offered the public in #ahgi was much more dearly to be bought4 ,the lines were straighter1 narrower1 and in every way less natural than they had seemed two years before4 ,in #ahha-ahhb they progressed still more in unaccountability4 ,they had now become regular rule and compass lines1 as straight1 as even1 and as precise as any draughtsman could wish and quite what astronomic faith did not desire4 ,having thus donned the character1 they nevermore put it off4 ,now1 this curious evolution in depiction points1 rightly viewed1 to an absence of design4 ,it shows that ,schiaparelli started with no preconceived idea on the subject4 ,on the contrary1 it is clear that he shared to begin with the prevailing hesitancy to accept anything out of the ordinary4 ,nor did he overcome his reluctance except as by degrees he was compelled4 ,for the canals did not change their characteristics from one opposition to another2 the eye it was that learned to distinguish what it saw1 and the brain made better report as it grew familiar with the messages sent it4 ,in other words1 it is patent from these successive maps that the geometrical character of the #8canals' was forced upon ,schiaparelli by the things themselves1 instead of being1 as his critics took for granted1 foisted on them by him4 ,we have since seen the regularity of the canals so undeniably that we are not now in need of such inferential support to help us to the truth2 but too late1 as it is1 to be of controversial moment the deduction is none the less of some corroboratory force4 ,with the third period enters what has been done since ,schiaparelli's time4 ,for that master was obliged1 from failing sight1 to close his work with the opposition of #ahij4 ,in #ahib ,w4 ,h4 ,pickering at ,arequipa was the chief observer of the planet and made two important discoveries3 one was the detection of small round spots scattered over the surface of the planet and connected with the canal system2 the other the perception of what seemed to him more or less irregular lines traversing the ,mare ,erythraeum4 ,both were notable detections4 ,the first set of phenomena he called lakes1 the second river-systems1 sometimes schematically #8canals1' but without committing himself to canaliform characteristics as his drawings make clear4 ,the same phenomena were seen at that opposition at the ,lick1 by ,schaeberle1 ,barnard and others1 and called streaks4 ,these discoveries took from the maria their supposed character of seas--a most important event in knowledge of ,mars4 ,illustration3 ,map ,,ix4 ,lowell1 #ahid4 ,illustration3 ,map ,x4 ,lowell1 #ahif4 ,illustration3 ,map ,,xi4 ,lowell1 #aija4 ,illustration3 ,map ,,xii4 ,lowell1 #aije4 ,the next advance was the detection at ,flagstaff in #ahid of their canaliform characteristics by my then assistant ,mr4 ,douglass1 who in place of the irregular streaks and river-systems of his predecessors found the seas to be crossed by lines as regular and as regularly connected as the canals in the light regions4 ,to him they appeared broad and ill defined1 but so habitually did to him the canals in the light areas1 while for directness and uniformity the one set showed as geometrically perfect as the other4 ,all the dark maria of the southern hemisphere he found to be laced with them and that they formed a network over the dark regions1 counterparting that over the light4 ,still more significant was the fact that their points of departure coincided with the points of arrival of the bright-region canals1 so that the two connected to form in its entirety a single system4 ,after the publication of his results 7,lowell ,observatory ,annals1 ,volume ,i1 #ahie7 ,schiaparelli identified some of those in the ,syrtis with what he had himself seen there in #ahhh 7,memoria1 ,,vi1 #ahii71 though his own had not been sufficiently well seen of him to impress him as canals4 ,of other additions to our knowledge since made by the writer the present book treats2 as also of the theory they originally suggested to him and which his later observations have only gone to confirm4 ,,chapter ,,iv ,,the ,,polar ,,caps ,almost as soon as magnification gives ,mars a disk that disk shows markings1 white spots crowning a globe spread with blue-green patches on an orange ground4 ,the smallest telescope is capable of this far-off revelation2 while with increased power the picture grows steadily more articulate and full4 ,with a two and a quarter inch glass the writer saw them thirty-five years ago4 ,after the assurance that markings exist the next thing to arrest attention is that these markings move4 ,the patches of color first made out by the observer are shortly found by him to have shifted in place upon the planet4 ,and this not through mistake on his part but through method in the phenomena2 for all do it alike4 ,in orderly rotation the features make their appearance upon the body's righthand limb 7in the telescopic image71 travel across the central meridian of the disk and vanish over its lefthand border4 ,one follows another1 each rising1 culminating and setting in its turn under the observer's gaze4 ,a constantly progressing panorama passes majestically before his sight1 new objects replacing the old with a march so steady and withal so swift that a few minutes will suffice to mark unmistakably the fact of such procession4 ,but for all this ceaseless turning under his gaze1 after a certain lapse of time it is evident that the same features are being shown him over again4 ,with such recognition of recurrence comes the first advance toward acquaintance with the ,martian world4 ,for that in all their journeying their configuration alters not1 proves them permanent in place1 part and parcel of the solid surface of that other globe4 ,this surface1 then1 lies exposed to view and by its turning shows itself subject1 like our earth1 to the vicissitudes of day and night4 ,in such self-exposure ,mars differs from all the four great planets1 ,jupiter1 ,saturn1 ,uranus and ,neptune4 ,features1 indeed1 are apparent on the first two of these globes and dimly on the other two as well1 but they lack the stability of the ,martian markings4 ,they are forever exchanging place4 ,in the case of ,jupiter what we see is undoubtedly a cloud-envelop through which occasional glimpses may possibly be caught of a chaotic nucleus below4 ,with ,saturn it is the same2 and the evidence is that the like is true of ,uranus and ,neptune4 ,what goes on under their great cloud canopies we can only surmise4 ,with ,mars1 however1 we are not left to imagination in the matter but so far as our means permit can actually observe what there takes place4 ,except for distance1 which1 through science1 year by year grows less1 it is as if we hovered above the planet in a balloon1 with its various features spread out to our gaze below4 ,attention shows these areographic features to be on hand with punctual precision for their traverse of the disk once every twenty-four hours and thirty-seven minutes4 ,for over two hundred years this has been the case1 their untiring revolutions having been watched so well that we know the time they take to the nicety of a couple of hundredths of a second4 ,we thus become possessed of a knowledge of the length of the ,martian day and it is not a little interesting to find that it very closely counterparts in duration our own1 being only one thirty-fifth the longer of the two4 ,we also find from the course the markings pursue the axis about which they turn2 and just as the period of the rotation tells us the length of the ,martian day so the tilt of the axis1 taken in connection with the form of the orbit1 determines the character of the ,martian seasons4 ,here again we confront a curious resemblance in the circumstances of the two planets1 for the tilt of the equator to the plane of the orbit is with ,mars almost precisely what it is for the ,earth4 ,the more carefully the two are measured the closer the similitude becomes4 ,sir ,william ,herschel made the ,martian #bh1 ,schiaparelli reduced this to #be1 and later determination by the writer puts it nearer #bd4 ,the latter is the one now adopted in the ,british ,nautical ,almanac for observers of the planet4 ,this is a very close parallelism indeed2 so that in general character the ,martian seasons are nearly the counterpart of ours4 ,in length1 however1 they differ2 first because the year of ,mars is almost double the length of the terrestrial one and secondly because from the greater ellipticity of ,mars' orbit the seasons are more unequal than is the case with us1 some being run through with great haste1 others being lingered on a disproportionate time4 ,it is usual on the ,earth to consider spring as the period from the vernal equinox1 about ,march #ba1 to the summer solstice1 about ,june #bj2 summer as lasting thence to the autumnal equinox2 autumn from this latter date1 about ,september #bj1 to the winter solstice on ,december #ba2 and winter from that point on to the next spring equinox again4 ,on this division our seasons in the northern hemisphere last respectively3 spring1 #ia days2 summer1 #ib days2 autumn1 #ib days2 and winter1 #ij days4 ,on ,mars these become1 reckoned in our days3 spring1 #aii days2 summer #ahc days2 autumn1 #adg days2 and winter1 #aeh days4 ,if we had counted them in ,martian days they would have totaled about one thirty-fifth less in number each4 ,in its days and seasons1 then1 ,mars is wonderfully like the ,earth2 except for the length of the year we should hardly know the difference in reckoning of time could we some morning wake up there instead of here4 ,only in one really unimportant respect should we feel strange2 in months we should find ourselves turned topsy-turvy4 ,but lunations have nothing to do with climate nor with the alternation between night and day2 and in these two important respects we should certainly feel at home4 ,though the axis could be determined by the daily march of any marking and thus the planet's tropic1 temperate and polar regions marked out1 the process is made easier by the presence of white patches covering the planet's poles and known1 in consequence1 as the polar caps4 ,it is from measures of the patches that the position of the ,martian poles has actually been determined4 ,these polar caps are exactly analogous in general position to those which bonnet our own ,earth4 ,they reproduce the appearance of the ice and snow of our arctic and antarctic regions seen from space1 in a very remarkable manner4 ,in truth they are things of note in more ways than one and would claim precedence on many counts4 ,priority of recognition1 however1 alone entitles them to premier consideration4 ,among the very first of the disk's detail to be made out by man1 they justly demand description first4 ,with peculiar propriety the polar caps have thus the pas4 ,not only do they stand first in order of visibility1 but they prove to occupy a like position logically when it comes to an explanation of the planet's present physical state4 ,it is not matter of hazard that the most evident of all the planet's markings should also be the most fundamental1 the fountainhead from which everything else flows4 ,it is of the essence of the planet's condition and furnishes the key to its comprehension4 ,the steps leading to this conclusion are as interesting as they are cogent4 ,they start at the polar caps' visibility4 ,for their size first riveted man's attention and then attention to them disclosed that most vital of the characteristics of the planet's surface3 change4 ,just as almost all of the features we note are permanent in place1 showing that they belong to the surface1 so are they all impermanent in character4 ,change is the only absolutely unchanging thing except position about the features the planet presents to view4 ,it was in the aspect of the polar caps that this important fact first came to light4 ,not only did they thus initially instance a general law1 they have turned out to make it2 for by themselves changing they largely cause change in all the rest4 ,but for a long time they alone exemplified its workings4 ,to ,sir ,william ,herschel we owe the first study of their change in aspect4 ,this eminent observer noted that their varying size was subject to a regular rhythmic wax and wane timed to the course of the seasons of the planet's year4 ,the caps increased in the winter of their hemisphere and decreased in its summer and being situate in opposite hemispheres they did this alternately with pendulum-like precision4 ,his observations were soon abundantly confirmed1 for the phenomena take place upon a vast scale and are thus easy of recognition4 ,at their maximum spread the caps cover more than one hundred times as much ground as when they have shrunk to their minimum4 ,in the depth of winter they stretch over much more than the polar zone1 coming down to #fj and even #ej of latitude north or south as the case may be1 thence melting till by midsummer they span only five or six degrees across4 ,in this they bear close analogue to the behavior of our own4 ,ours would show not otherwise were they viewed from the impersonal standpoint of space4 ,very little telescopic aid suffices to disclose the ,martian polar phenomena in this their more salient characteristics and convince an observer of their likeness to those of the earth4 ,any one may note what is there going on by successive observations of the planet with a three-inch glass4 ,nor is the change by any means slow4 ,a few days at the proper ,martian season1 or at most a couple of weeks1 produces conspicuous and conclusive alterations in the size of these nightcaps of the planet's winter sleep4 ,resembling our own so well they were early surmised to be of like constitution and composed1 therefore1 of ice and snow4 ,plausible on its face1 this view of them was generally adopted and common sense has held to it ever since4 ,it has encountered1 of course1 opposition1 partly from very proper conservatism1 but chiefly from that earth-centred philosophy which has doubted most advances since ,galileo's time1 and carbonic acid has been put forward by this school of sceptics to take its place4 ,we shall critically examine both objections2 the latter first1 because a certain physical fact enables us to dispose of it at once4 ,in casual appearance there is not much to choose between the rival candidates of common sense and uncommon subtlety1 water and frozen carbonic acid gas1 both being suitably white and both going and coming with the temperature4 ,but1 upon closer study1 in one point of behavior the two substances act quite unlike1 and had half the ingenuity been expended in testing the theory as in broaching it this fact had come to light to the suggestors as it did upon examination to the writer and had served as a touchstone in the case4 ,at pressures of anything like one atmosphere or less carbonic acid passes at once from the solid to the gaseous state4 ,water1 on the other hand1 lingers in the intermediate stage of a liquid4 ,now1 as the ,martian cap melts it shows surrounded by a deep blue band which accompanies it in its retreat1 shrinking to keep pace with the shrinkage in the cap4 ,this is clearly the product of the disintegration since it waits so studiously upon it4 ,the substance composing the cap1 then1 does not pass instantaneously or anything like it from the solid to the gaseous condition4 ,this badge of blue ribbon about the melting cap1 therefore1 conclusively shows that carbonic acid is not what we see and leaves us with the only alternative we know of3 water4 ,,chapter ,v ,,behavior ,,of ,,the ,,polar ,,caps ,assured by physical properties that our visual appearances are quite capable of being what they seem we pass to the phenomena of the cap itself4 ,like as are the polar caps of the two planets at first regard1 upon further study very notable differences soon disclose themselves between the earthly and the ,martian ones2 and these serve to give us our initial hint of a different state of things over there from that with which we are conversant on ,earth4 ,to begin with1 the limits between which they fluctuate are out of all proportion greater on ,mars4 ,it is not so much in their maxima that the ice-sheets of the two planets vary4 ,our own polar caps are much larger than we think2 indeed1 we live in them a good fraction of the time4 ,our winter snows are in truth nothing but part and parcel of the polar cap at that season4 ,now1 in the northern hemisphere snow covers the ground at sea-level more or less continuously down to #ej of latitude4 ,it stretches thus far even on the western flanks of the continents1 while in the middle of them and on their eastern sides it extends ten degrees farther yet during the depth of winter4 ,so that we have a polar cap which is then ninety degrees across4 ,in our southern hemisphere it is much the same six months later1 in the corresponding winter of its year4 ,on ,mars at their winter maxima the polar caps extend over a similar stretch of latitude4 ,they do so1 however1 unequally4 ,the southern one is considerably the larger4 ,in #aijc1 #acf days after the winter solstice1 in the ,martian calendar ,february #bg1 it came down in longitude #bbe to #dd of latitude and may be taken to have then measured ninety-three degrees across2 in #aije1 #aba days after the same solstice1 it stretched in longitude #bce to latitude #db1 and #aeh days later1 in longitude #bba to latitude #da2 values which1 supposing it to have been round1 imply for it a diameter on these occasions of ninety-six and ninety-seven degrees4 ,it was then ,february #bj and ,march #aj respectively of the ,martian year4 ,these determinations of its size at the two oppositions agree sufficiently well considering the great tilt away from us of the south pole at the time and the horizonward foreshortening of the edge of the snow4 ,it seems from a consensus of the measures to have been some five degrees wider in #aijc than in #aije1 which may mean a colder winter preceding the former date4 ,the cap was still apparently without a dark contour in both years1 showing that it had not yet begun to melt4 ,illustration3 ,south ,polar ,cap4 7,lowell ,observatory1 #aije47 ,less has been learnt of the northern cap4 ,in #ahif-ahig when it was similarly presented skirting the other rim of the disk1 a gap occurred in the observations corresponding to the time by ,martian months between ,february #bd and ,march #bb4 ,on the former date the cap came down only to latitude #ee in longitude #ceb2 on the subsequent one and for several days after the latitude of the southern limit of the snow was such as to imply a breadth to it of about eighty degrees4 ,the cap was now bordered by a dark line1 proving that melting had already set in4 ,it cannot1 however1 at its maximum have covered much more country than this1 in view of its lesser extent on ,february #bd4 ,fair as our knowledge now is of the dimensions of the ,martian polar caps at their maxima1 we have much more accurate information with regard to their minima1 and this1 too1 was obtained much earlier4 ,that we should first have known their smallest rather than their greatest extent with accuracy may appear surprising1 exactly the opposite being our knowledge of our own4 ,it is not1 however1 so surprising as it appears1 inasmuch as it is an inevitable consequence of the planet's aspect with regard to the sun4 ,when the tilt of the axis inclines one hemisphere toward the sun1 that hemisphere's polar cap must melt and dwindle1 while at the same time it is the one best seen1 the other being turned away from the sun and therefore largely from us as well2 so that even such part of the latter as is illumined lies low down toward the horizon of the disk where a slight change of angle means a great difference in size4 ,it has thus come about that both the south and the north polar caps have been repeatedly well seen and measured at their minimum2 and the measures for different ,martian years agree well with one another4 ,for the northern cap six degrees in diameter is about the least value to which it shrinks4 ,the south one becomes even smaller1 being usually not more than five degrees across1 while in #ahid it actually vanished1 a thing unprecedented4 ,its absence was detected by ,douglass at ,flagstaff and shortly after the announcement of its disappearance the fact was corroborated by ,barnard at the ,lick4 ,the position the cap would have occupied was at the time better placed for observation in ,america than in ,europe1 inasmuch as the cap is eccentrically situated with regard to the geographic pole and its centre was then well on the side of the disk presented to us while in ,europe it was turned away4 ,this1 together with the fact that it undoubtedly came and went more than once about this time1 accounts for its disappearance not having been recognized there1 haze left by it having apparently been mistaken for the cap itself4 ,illustration3 ,north ,polar ,cap4 7,lowell ,observatory1 #aije47 ,on ,earth the minima are much larger4 ,in the northern hemisphere the line of perpetual snow or pack-ice in longitude #ej east runs about on the #hj parallel1 including within it the southern end of ,franz ,joseph ,land4 ,opposite this1 in longitude #abj west1 above the ,north ,american continent1 it reaches down lower still to #ge4 ,so that the cap is then from twenty to thirty degrees in diameter4 ,in the southern hemisphere it is even larger4 ,in longitude #agj west the land was found by ,ross to be under perpetual snow in latitude #gb4 ,cook had reached in longitude #ajg east an impassable barrier of ice in latitude #gj #bc4 ,the season was then midsummer1 ,january #cj4 ,so that we are perhaps justified in considering #ga south as about the average limit of perpetual snow or paleocrystic ice4 ,this would make the southern cap at its minimum thirty-eight degrees across4 ,pack-ice with open spots extends still farther north4 ,the ,pagoda in #ahde was stopped by impenetrable pack-ice in south latitude #fh and the ,challenger in #ahgd encountered the pack in latitude #fe on the #aith of ,february1 which corresponds about to our #aith of ,august1 the time at which the sea should be most open4 ,the limit of perpetual snow is thus lower in the southern than in the northern hemisphere4 ,here again1 then1 the two minima differ1 but in the reverse way from what they do on ,mars4 ,from this we perceive that the variations in size of the caps are much more striking on ,mars than on the ,earth and that these are due chiefly to the difference in the minima1 the maxima not varying greatly4 ,to explain these interesting diversities of behavior in the several polar caps we shall have to go back a little in general physics in order to get a proper take off4 ,it is a curious concomitant of the law of gravity that the amount of heat received by a planet in passing from any point of its path to a point diametrically opposite is always the same no matter what be the eccentricity of the orbit4 ,thus1 a planet has as many calories falling upon it in travelling from its vernal equinox to its autumnal as from the autumnal to the vernal again1 although the time taken in the one journey be very different from that of the other4 ,this is due to the fact that the angle swept over by the radius vector1 that is1 the imaginary bond between it and the sun1 is at all points proportional to the amount of heat received2 just as it is of the gravity undergone1 the two forces radiating into space as the inverse square of the distance4 ,thus the heat received by a point or a hemisphere1 through any orbital angle1 is independent of the eccentricity of the orbit4 ,but it is not independent of the axial tilt4 ,for the force of the sun's rays is modified by their obliquity4 ,the amount of heat received at any point in consequence of the tilt turns upon the position of the point1 and for any hemisphere taken as a whole it depends upon the degree to which the pole is tilted to the source of heat4 ,in consequence of being more squarely presented to its beams1 the hemisphere which is directed toward the sun and therefore is passing through its summer season gets far more insolation than that which is at the same time in the depth of its winter4 ,for a tilt of twenty-four degrees1 the present received value for the axis of ,mars1 the two hemispheres so circumstanced get amounts of heat respectively in the proportion of sixty-three to thirty-seven4 ,but1 though the summer and winter insolation thus differ1 they are the same for each hemisphere in turn4 ,consequently the mere amount of heat received cannot be the cause of any differences detected between the respective maxima and minima of the two polar caps4 ,if heat were a substance which could be stored up instead of being a mode of motion1 the effect produced would be in accordance with the quantity applied and the two caps would behave alike4 ,as it is the total amount has very little to say in the matter4 ,not the amount of heat but the manner in which this heat is made at home is responsible for the difference we observe4 ,now1 though the total amount is the same in passing from the vernal to the autumnal equinox as from the autumnal to the vernal1 the time during which it is received in either case varies from one hemisphere to the other4 ,it is summer in the former while it is winter in the latter and the difference in the length of the two seasons due to the eccentricity of the orbit makes a vast difference in the result4 ,winter affects the maxima1 summer the minima1 attained4 ,of these opposite variations presented to us by the two caps1 the maxima1 the one most difficult to detect1 is the easiest to explain1 for the difference in the maxima seems to be due to the surpassing length of the antarctic night4 ,owing to the eccentricity of the orbital ellipse pursued by ,mars and to the present position of the planet's solstices1 the southern hemisphere is farther away from the sun during its winter and is so for a longer time4 ,the seasons are in length1 for the northern hemisphere3 spring1 #aii days2 summer1 #ahc days2 autumn1 #adg days2 and winter1 #aeh days2 while for the southern hemisphere they are3 spring1 #adg days2 summer1 #aeh days2 autumn1 #aii days2 and winter1 #ahc days4 ,the arctic polar night is thus #cje of our days long2 the antarctic1 #chb4 ,thus for #gg more days than happens to its fellow the southern pole never sees the sun4 ,now1 since the total sunlight from equinox to equinox is the same in both hemispheres1 its distribution by days must be different4 ,in the southern hemisphere the same amount is crowded into a smaller compass in the proportion of #cje to #chb2 that being that hemisphere's relative ratio of days4 ,but since during winter the cap increases1 there is a daily excess of accumulation over dissipation of snow and each twenty-four hours must on the average add its tithe to the sum total4 ,since the northern days are the warmer each adds less than do the southern ones2 and furthermore there are fewer of them4 ,on both these scores the amount of the deposition about the northern pole should be less than about the southern one4 ,consequently1 the snow-sheet there should be the less extensive and show a relatively smaller maximum1 which explains what we see4 ,with the minima the action is otherwise4 ,inasmuch as the greater heat received during the daylight hours by the southern hemisphere is exactly offset by the shortness of its season1 it would seem at first as if there could be no difference in the total effect upon the two ice-caps4 ,but further consideration discloses a couple of factors which might1 and possibly do1 come in to qualify the action and account for the observed effect4 ,one is that though the total amount of heat received is the same1 the manner of its distribution differs in the two hemispheres4 ,in the northern one the time from vernal to autumnal equinox is #chb days against #cje in the southern4 ,consequently1 the average daily heat is then five fourths more intense in the southern hemisphere4 ,indeed1 it is even greater than this and nearer four thirds1 because the melting occurs chiefly in the spring and in the first two months of summer when the contrast in length of season between the two hemispheres is at its greatest4 ,now1 a few hotter days might well work more result than many colder ones4 ,and this would be particularly true of ,mars where the mean temperature is probably none too much above the freezing-point to start with4 ,ice consumes so much caloric in the process of turning into any other state1 laying it by in the form of latent heat before it can turn into water and then so much more before this water can be converted into steam that a good deal has to be expended on it before getting any perceptible result4 ,once obtained1 however1 the heat is retained with like tenacity4 ,so that the process works to double effect6 ,if sufficient heat be received the ice is first melted1 then evaporated and finally formed into a layer of humid air1 the humidity of which keeps it warm4 ,dry air is unretentive of heat1 moist air the opposite4 ,and for the melting of the ice-cap to proceed most effectively the temperature that laps it about must be as high as possible and kept so as continuously as may be4 ,if between days it be allowed to fall too low at night much caloric must needs be wasted in simply raising the ice again to the melting-point4 ,this a blanket of warm air tends to prevent1 and this again is brought about by a few hot days rather than by many colder ones4 ,it is not all the heat received that becomes effective but the surplus heat above a certain point4 ,the gain in continuity of action thus brought about is somewhat like that exhibited between the running of an express and an accommodation train4 ,to reach its destination in a given time the former requires far less power because it does not have to get up speed again after each arrest4 ,thus the whole effect in melting the snow would be greater upon that hemisphere whose summer happens to be the more intense4 ,the greater swing in size of the cap most exposed to the effects of the eccentricity is1 then1 the necessary result of circumstances when the precipitation is not too great to be nearly carried off by the subsequent dissipation4 ,this is the state of things on ,mars and the second of the factors above referred to4 ,on the ,earth as we have seen the polar caps are somewhat larger at their maximum and very much so at their minimum4 ,now1 this is just what should happen were the precipitation increased4 ,suppose1 for example1 that the amount of precipitation were to increase while the amount of summer melting remained the same1 and this would be the case if the vapor in the air augmented for one cause or another1 and the result of each fresh deposit was locked up in snow4 ,after a certain point the cap would grow in depth rather than in extension2 the winter deposit would be thicker but the summer evaporation would remain the same4 ,now1 if this occurred1 it is evident that the minimum size of the cap would increase relatively much faster than the maximum1 and furthermore1 that the relative increase of the minimum in the two caps would be greatest for that which had seasons of extremes4 ,the result we see in the case of the ,earth4 ,in the arctic cap1 where in consequence of the eccentricity of the orbit the winter is shorter1 the maximum is less than in the antarctic and this extra amount of precipitation cannot be wholly done away with in its intenser summer1 so that the minimum too is greater there4 ,we reach1 then1 this interesting conclusion4 ,we find that eccentricity of orbit by itself not only causes no universal glaciation in the hemisphere which we should incidentally suppose likely to show it1 but actually produces the opposite result1 in more than offsetting by summer proximity what winter distance brings about4 ,to cause extensive glaciation we must have1 in addition to favorable eccentricity1 a large precipitation4 ,with these two factors combined we get an ice age1 but not otherwise4 ,the result has an important bearing on geologic glacial periods and their explanation4 ,once formed1 an ice-sheet cools everything about it and chills the climate of its hemisphere4 ,it is a perpetual storehouse of cold4 ,mars has no such general glaciation in either hemisphere1 and the absence of it1 which is due to lesser precipitation1 together with the clearness of its skies1 accounts for the warmth which the surface exhibits and which has been found so hard hitherto to interpret4 ,could our earth but get rid of its oceans1 we too might have temperate regions stretching to the poles4 ,,chapter ,,vi ,,martian ,,polar ,,expeditions ,polar expeditions exert an extreme attraction on certain minds1 perhaps because they combine the maximum of hardship with the minimum of headway4 ,inconclusiveness certainly enables them to be constantly renewed1 without loss either of purpose or prestige4 ,the fact that the pole has never been trod by man constitutes the lodestone to such undertakings2 and that it continues to defy him only whets his endeavor the more4 ,except for the demonstration of the polar drift-current conceived of and then verified by ,nansen1 very little has been added by them to our knowledge of the globe4 ,nor is there specific reason to suppose that what they might add would be particularly vital4 ,nothing out of the way is suspected of the pole beyond the simple fact of being so positioned4 ,yet for their patent inconclusion they continue to be sent in sublime superiority to failure4 ,martian polar expeditions1 as undertaken by the astronomer1 are the antipodes of these pleasingly perilous excursions in three important regards1 which if less appealing to the gallery commend themselves to the philosopher4 ,they involve comparatively little hardship2 they have accomplished what they set out to do2 and the knowledge they have gleaned has proved fundamental to an understanding of the present physical condition of the planet4 ,the antithesis in pole-pursuing between the two planets manifests itself at the threshold of the inquiry1 in the relative feasibility with which the phenomena on ,mars may be scanned4 ,for1 curiously enough1 instead of being the pole and its surrounding paleocrystic ice which remains hidden on ,mars1 it is rather the extreme extent of its extension and the lowest latitudinal deposit of frost which lies shrouded in mystery4 ,the difficulty there is not to see the pole but to see in winter the regions from which our own expeditions set out4 ,and this because the poles are well displayed to us at times which are neither few nor very far between2 while favorable occasions for marking the edge of the caps when at their greatest have neither proved so numerous nor so favorable4 ,the tilt of the planet's axis when conveniently placed for human observation has been the cause of the one drawback2 the planet's meteorological condition in those latitudes at that season the reason for the other4 ,what knowledge we have of the size of the caps in degrees upon the surface of the planet at this their extreme equatorward extension has been given in the last chapter4 ,their aspect at the time together with what that aspect betokens was not there touched upon4 ,with it1 therefore1 and the peculiarities it presents to view we shall begin our account of the caps' annual history4 ,illustration3 ,south ,polar ,cap in winter4 ,when first the hemisphere1 the pole of which has for half a ,martian year been turned away from the sun1 begins to emerge from its long hibernation1 the snow-cap which covers it down even to temperate regions presents an undelimited expanse of white1 the edges of which merge indistinguishably into the groundwork color of the regions round about4 ,of a dull opaque hue along its border1 its contour is not sharp but fades off in a fleecy fringe without hard and fast line of demarcation4 ,such notably was the aspect of the north temperate zone in #ahif when1 tilted as it then was away from us into a mere northern horizon of the planet's limb1 it showed prior to the definite recognition of the north polar cap in ,august of that year1 and such too was the look of the disk's southern edge both before and after the first certain detection of the southern cap in #aijc and #aije4 ,each was then in the depth of winter4 ,for in ,martian chronology the season corresponded in each at the time to what we know in our northern hemisphere as the latter part of ,february and the early part of ,march and the appearance of the planet's surface in both was not unlike what we know at the same season in latitude #de4 ,indeed1 there is reason to suppose bad weather there then and the extreme fringe1 from the pale tint it exhibited1 to have been cloud rather than snow4 ,it is quite in keeping with what we know on earth or can conceive of elsewhere that such aspect should characterize the cap at or near the attainment of its greatest development4 ,whether it were not yet quite arrived at this turning-point of its career or had but slightly passed it a vagueness of outline would in either event proclaim the fact4 ,for were the frost still depositing1 the cap's edge would show indefinite2 and on the other hand had it just begun to melt1 evaporation would give it an undefined edge before the melting water had gathered in sufficient quantities to be itself noticeable4 ,its behavior subsequent to recognition bore out the inference from its aspect when it first appeared4 ,while for many days prior to its coming unmistakably into view it was impossible to say whether what was seen of the southern cap in #aijc and #aije was cloud or snow2 so even after it had definitely disclosed itself it continued to play at odds with the observer4 ,showing sharp at the edges one day it would appear but hazily defined the next1 thus clearly demonstrating itself to be at the then unstable acme of its spread4 ,such a state of things we are only too familiar with in our own ,march weather when after days of sunshine that have melted off the winter's white and fringed it with rivulets and awakening grass1 a snow-storm falling upon it powders the ground again that was beginning to be bare and at one stroke extends the domain of the snow while mystifying the actual limits it may be said to occupy4 ,the same condition of things1 then1 is not unknown on ,mars1 and to fix the precise date of so wavering a phenomenon is not so much matter of difficult observation as of physical impossibility4 ,illustration3 ,hellas in winter4 ,nor is the southern cap1 at this the height of its winter expansion1 confined strictly to its own proper limits4 ,faint extensions1 now so connected with its main body as to form part and parcel of it1 now so detached and dull of tint as to make the observer doubtful of the exact relationship1 are generally to be seen attendant on it4 ,hellas in winter is much given to such questionable garb1 and has in consequence been mistaken by more than one observer for the cap itself1 appearing as it does well upon the southern limb and being often the only region to show white4 ,indeed1 frost-bound as it then is1 to consider it the polar cap1 though possibly geographically incorrect1 may climatologically be sustainable4 ,its northern extremity extends down to latitude #cj1 a pretty low latitude for frost4 ,still such equatorward extension is not without corroborating parallel4 ,in #aijc1 at what was in ,martian dates ,april #bf1 the whole of the region south of the ,solis ,lacus and the ,nectar showed white1 with a whiteness which may as well have been hoarfrost as cloud4 ,now1 the ,nectar runs east and west in latitude #bh4 ,so that in this instance1 too1 it is possible that arctic conditions knocked at the very doors of the tropics4 ,encroachment of the sort is equivalent to snow in ,cairo and permanent snow at that2 not an occasional snow flurry1 but something to linger on the ground and stay visible sixty millions of miles away4 ,illustration3 ,white south of ,nectar and ,solis ,lacus4 ,knowledge of either cap in this the midwinter of its year has been a matter of the most recent oppositions of the planet4 ,up to within the last few years our acquaintance with either cap was chiefly confined to the months1--one might almost say the weeks1--immediately surrounding the summer solstice of its respective hemisphere4 ,the behavior of the caps during the rest of their career was largely unknown to us1 from the very disadvantageous positions they occupied at the times the planet was nearest to the earth4 ,beginning with #ahid1 however1 our knowledge of both has been much extended1 by a proportionate extension of the period covered by the observations4 ,it used to be thought impracticable to observe the planet far on either side of opposition2 now it is observed from as much as four months before that event to the same period after it4 ,the result is a systematic series of observations which in many ways has given unexpected insight into ,martian conditions4 ,one of the benefits secured has been the lengthening of the period of study of the cap's career1 a pushing of inquiry farther back into its spring history and a longer lingering with it in its autumnal rebuilding4 ,yet up to the very last opposition a gap in its chronology still remained between ,february #be and ,april #a4 ,the opposition of #aije has bridged this hiatus and brought us down to the latter date1 at which the melting of the cap begins in earnest4 ,from this point1 ,april #a on1 we have abundant evidence of the cap's behavior4 ,its career now for some time is one long chronicle of contraction4 ,like ,balzac's ,peau de ,chagrin it simply shrinks1 giving out of its virtue in the process4 ,the cap proceeds to dwindle almost under the observer's eye till1 from an enormous white counterpane spread over all the polar and a large part of the temperate zone1 its area contracts to but the veriest nightcap of what it was before4 ,from seventy degrees across it becomes sixty1 then fifty1 then forty1 till by the middle of the ,martian ,may it has become not more than thirty degrees in diameter4 ,during this time1 from the moment the melting began in good earnest1 the retreating white is girdled by a dark band1 of a blue tint1 which keeps pace with the edge of the cap1 shrinking as it shrinks1 and diminishing in width as the volume of the melting decreases4 ,after the melting has been for some time under way and the cap has become permanently bordered by its dark blue band a peculiar phenomenon makes its appearance in the cap itself4 ,this is its fission into one or more parts4 ,the process begins by the appearance of dark rifts which1 starting in from the cap's exterior1 penetrate into its heart until at last they cleave it in two4 ,rifts have been seen by several observers and in both caps2 and what is most suggestive they always appear in the same places1 year after year4 ,sometimes oppositions elapse between their several detections for they are not the least difficult of detail2 but when they are caught1 they prove to lie just where they did before4 ,the permanency in place of the rifts1 a characteristic true of them all1 shows them to be of local habit4 ,thus the rift of #ahhd and #ahig reappeared again to another observer in the same position in #aija4 ,they are1 therefore1 features of1 or directly dependent on1 the surface of the planet4 ,but it will not do from this fact to infer that they are expressive of depressions there4 ,the evidence is conclusive that great irregularities of surface do not exist on ,mars4 ,as we shall see when we come to consider the orology of the planet it is certain that elevations there of over two or three thousand feet in altitude are absent4 ,differences of temperature1 able to explain a melting of the ice in one locality coincidentally with its retention in an adjacent one1 must in consequence be unknown4 ,and this much more conclusively than at first appears1 for the reason that the smaller the planet's mass the less rapidly does its blanket of air thin out in ascent above the surface4 ,this is in consequence of the greater pull the larger body exerts and the greater density it imparts to a compressible gas like our atmosphere4 ,gravity acts like any force producing pressure and by it the envelope of air is squeezed into a smaller compass4 ,but as this is done throughout the atmospheric layer it means a more rapid rarefaction as one leaves the body4 ,the action is such that the height necessary to reach an analogic density varies inversely as the gravity of the mass4 ,in consequence of this1 to compass a relative thermometric fall for which a moderate difference of elevation would suffice on ,earth1 an immoderate one must be made on ,mars4 ,for gravity there being but three eighths what it is here1 eight thirds the rise must be made to attain a proportionate lowering of temperature4 ,this fact renders the above argument against elevation and depression being the cause of the phenomenon three times as cogent as it otherwise would be4 ,with so gradual a gradient in barometric pressure there and so low a set of contour lines1 altitude must be a negligible factor in ,martian surface meteorologic phenomena4 ,both density and temperature can be but little affected by such cause1 and we must search elsewhere for explanation of what surface peculiarities we detect4 ,meanwhile the rifts themselves1 from being lines which penetrate the cap from its periphery in toward its centre1 end by traversing it in its entirety and separating portions which1 becoming outlying subsidiary patches1 themselves proceed to dwindle and eventually disappear4 ,the rifts usually take their rise from such broader parts of the cap-encircling blue belt as make beads upon that cordon and are clearly spots where the product of the melting of the cap is either specially collected1 or produces its most visible effect4 ,so far the description might apply with substantial accuracy to either cap4 ,yet the conduct of the two is in some ways diverse and begins to accentuate itself from this point on4 ,illustration3 ,northern ,cap hooded with vapor4 ,from the time that the north polar cap reaches a diameter of about twenty-five degrees1 a singular change steals over it4 ,from having been up to then of a well-defined outline it now proceeds to grow hazy and indistinct all along its edge4 ,this change in its character at the same period of its career has been quite noticeable at each of the three last oppositions1 so that small doubt remains that the metamorphosis is a regularly recurrent one in the history of the cap4 ,coincident with the obliteration of its contour1 its dimensions seemingly enlarge4 ,it is as if a hood had been drawn over the cap of a dull white different from the dazzling brilliance of the cap itself and covering more ground4 ,such is probably what occurs2 with vapor for veil4 ,the excessive melting of the cap produces an extensive evaporation which then in part condenses to be deposited afresh1 in part remains as a covering1 shutting off from our view the outlines of the cap itself4 ,it would seem that at this time the cap melts faster than the air can carry it off4 ,a sort of steaming appears to be going on1 taking place in situ4 ,for it clearly is not wafted away4 ,the time of its coming too is significant4 ,for the season is ,may #ae1 the height of time for a spring haze to set in4 ,then later it dissipates with the same quiet indefiniteness with which it gathered4 ,illustration3 ,northern ,cap unmasked4 ,it is some time in ,martian ,june before the spring haze clears away1 and when it does go1 only a tiny polar cap stands revealed beneath it1 from six to eight degrees across1 or from a tenth to a fifteenth of what it was when it passed into its curious spring chrysalis4 ,the date of emergence varies4 ,in #aijc it occurred early1 the haze not being marked after ,june #c1 though recurring again at intervals for a day or so4 ,in #aije it was later2 perceptibly thin after ,june #ba it did not certainly clear away till ,june #i and came back again on ,july #af and possibly on the #beth4 ,these vicissitudes of aspect give us glimpses into a sweet unreasonableness in ,martian weather which makes it seem more akin to our own4 ,and this on two counts1 diurnal and annual4 ,from day to day atmospheric conditions shift for purely local cause2 while1 furthermore1 successive ,martian years are not alike4 ,in some the season is early2 in others late4 ,so that ,mars is no more exempt than are we from the wantonness of weather4 ,clearly disclosed thus reduced to its smallest possible terms it remains for some months of our days1 for six weeks of its own4 ,during that period it continues practically unchanged1 neither increasing nor decreasing significantly in size1 nor altering notably in aspect4 ,measures of the drawings of it then make it from five to eight degrees across and it is possible that it really fluctuates between narrow limits1 though its clear-cut outline at all times renders the variation difficult to explain4 ,we are not so near it as we could wish2 for on these occasions even at their best it is over two hundred times as distant as the moon and the greatest magnification possible still leaves it a hundred thousand miles away4 ,to the south polar cap a somewhat similar history attaches1 but with a difference4 ,in its case no such regularly recurrent spring haze has yet been noted4 ,the melting of this cap would seem to be of a more orderly nature than its fellow and not to outdo what can conveniently be carried off4 ,that an excess of evaporation should not take place is the more peculiar from the fact that at its maximum it is the larger of the two and therefore has the greater quantity of matter to get rid of4 ,its summer1 also1 is shorter than the arctic one1 so that it has the less time to dispose of its accumulations4 ,the only other respect in which it seems to be differently circumstanced from its antipodes is in the character of its surroundings4 ,about it are large blue-green areas which with intermissions stretch down in places to within less than ten degrees of the equator2 whereas the other pole is continuously encircled for long distances by practically uninterrupted ochre4 ,the character of the environment seems thus the only thing that can account for the difference in behavior and this proves the more plausible when we come to consider what those two classes of regions respectively represent4 ,in other ways as well the southern cap is the more self-contained4 ,the rifts1 indeed1 break it up into separate portions and these in part remain as outlying detachments of the main body1 as was notably the case in #ahgg and in #ahid1 but they hardly have the permanency and importance of those similarly formed about the arctic pole4 ,nothing antarctic for instance compares with the subsidiary patch of the north polar regions lying in longitude #bjf1 which both in ,schiaparelli's time1 and during the late oppositions as well was almost as fixed a feature of the arctic zone as the cap proper4 ,not quite so constant1 however1 and not so solid-looking a landmark is this patch for all its extent1 which nearly equals the area of the more legitimate portion4 ,it bears on its face a more pallid complexion as if it were thinner1 and this is borne out by the fact that it occasionally disappears1 an event which so far at least has never befallen the northern cap itself4 ,less constant the southern one is to its own minimum than the northern4 ,in some seasons1 in most in fact1 it reaches like the other a more or less definite limit of diminution which it does not pass4 ,but this is not always the case4 ,in #ahid it disappeared entirely at the height of its midsummer4 ,the season was probably unusually hot then in the southern hemisphere of ,mars4 ,in position the caps have something to say about physiographic conditions4 ,both caps at their minima are then irregular and the centre of the south one is markedly eccentric to the areographic pole4 ,it lies some six degrees north along the thirtieth meridian4 ,the northern one is also probably eccentric1 but much less so1 with a divergence not much exceeding a degree and of doubtful orientation4 ,not only are both caps not upon their respective poles but they are not opposite each other1 the one lying in longitude #cj1 the other in #bij4 ,this speaks1 of course1 for local action4 ,in some wise this must depend on the configuration of the surface1 yet so far as markings go there is nothing to show what the dependence is4 ,the eccentring of the caps is paralleled by the like state of things on earth4 ,the pole of cold does not coincide in either hemisphere with the geographic pole4 ,on the earth its position is largely determined by the distribution of the land-masses4 ,continents are not such equalizers of heat as oceans because of their conductivity on the one hand and their immobility on the other4 ,in winter they part with their heat more quickly and convection currents cannot supply the loss4 ,this accounting for thermal pole eccentricity is inapplicable to ,mars because of the absence there of bodies of water4 ,and it is significant that the degree the earthly poles of cold are out much exceeds what is the case on ,mars4 ,possibly areas of vegetation there replace to some effect areas of water4 ,it is certainly in favor of this view that the arctic regions there are more desert than the antarctic and that the north pole of cold occupies more squarely the geographic pole4 ,not till #aijc did the actual starting again of either cap chance to be seen4 ,nor was this1 indeed1 a matter of hazard but of persistent inquiry by observation prolonged after the planet had got so far away that its scanning had hitherto been discontinued4 ,such search beyond the customary limits of observation was essential to success1 because of the relation of the axial tilt to the position of the planet in its orbit4 ,at an opposition well placed for nearness1 the tilt is such as largely to hide the pole and to present the polar regions too obliquely to view for effective scanning4 ,this is true both of the arctic and the antarctic regions in turn4 ,for the ,martian axis being inclined somewhat as our own is to the plane of the planet's orbit1 we at times see well and at times but poorly the arctic or antarctic zones4 ,the cap1 the starting to form of which was thus caught1 was the arctic one2 the date #abh days after the northern summer solstice1 or thereabouts1 for as is perhaps natural the advent of the phenomenon partook of the wavelike advance of such things familiar on earth1 an advance succeeded by a recession and then followed by another advance4 ,so much is proof of local weather there as here4 ,hoar-frost was successively deposited and then melted off4 ,illustration3 ,deposition of frost4 ,what is significant1 the deposition of the frost took place simultaneously over large areas4 ,the very first patch of it1 in about longitude #cbj1 extended at one stroke down to latitude #ee4 ,for it actually crossed the ,pierius somewhat to the south4 ,a second patch stretched to the east of the cap4 ,two wings these made to the kernel of cap itself4 ,through the wings could be marked the line of the canal3 the ,pierius upon the one side1 the ,enipeus upon the other4 ,such visibility of the canals through the white stretches proved the white not to be due to cloud suspended between us and them1 but a surface deposit which found no lodgment upon the canals themselves4 ,the same avoidance of dark markings was evidenced by the showing of the dark rim round the cap's kernel4 ,now1 if the deposit were indeed hoarfrost1 this failure to find permanent foothold on the dark markings is what we should expect to witness4 ,for whether they were vegetation or water1 equally in either case the frost would melt from them first4 ,probably they were both vegetal1 though some doubt might exist about the latter1 the band around the kernel4 ,it was then ,august #bj in that hemisphere4 ,such deposition over great stretches of country is perhaps not so surprising as it appears at first sight when seen from without in its totality4 ,after all1 something not unlike it occurs in our snow-storms when hundreds of square miles are whitened at once4 ,furthermore1 with an atmosphere as thin as ,mars seems to possess the temperature must be perilously near the freezing-point in the arctic and subarctic regions at the close of summer4 ,steadily1 with intermissions1 the white sheet increased until even the dark border to the cap became obliterate1 the kernel showing at first through the veil like the ghost of what it had been1 and then ceasing to be visible at all1 its delimitations being buried under deeper and deeper depositions of frost4 ,illustration3 ,first northern snow4 ,the perennial portion of the cap was thus merged in the new-fallen snow4 ,this marked the on-coming of the arctic winter in full force and happened even before the polar sun had wholly set4 ,for the pole did not enter into the shadow till two of our months later1 the autumnal equinox occurring #ahc days after the summer solstice or #ee days after the first fall of frost4 ,then the pole passed into its star-strewn arctic night1 a polar night of twice the duration of our own and the circumpolar regions entered upon their long hibernation of ten of our months4 ,,chapter ,,vii ,,white ,,spots ,in addition to the polar caps proper and to the subsidiary polar patches that often in late summer flank them round about1 other white spots may from time to time be seen upon the disk4 ,in appearance these differ in no respect1 so far as observed1 from the arctic subsidiary snow-fields4 ,of the same pure argent1 they sparkle on occasion in like manner with the sheen of ice4 ,equally with the polar caps they remain permanent in place during the period of their visibility and are themselves long-lived4 ,though by no means perpetual their duration is reckoned by weeks and even months1 and they recur with more or less persistency at successive ,martian years4 ,that1 when seen1 they show in particular positions apparently unaffected by diurnal change precludes their being clouds1 and this fact taken in connection with the character of their habitat is the puzzling point about them4 ,for they affect chiefly the north tropic belt4 ,they1 or at least their nuclei1 are small1 about two or three degrees in diameter1 and are not particularly easy of detection as a rule1 though certain larger ones are at times conspicuous4 ,chromatic1 rather than formal1 definition is necessary to their bringing out1 as is witnessed by the superb colors the disk presents at the times when they are best seen4 ,it is then that ,mars puts on the look of a fire-opal4 ,the first such spot to be noticed was one which ,schiaparelli detected in #ahgi1 at the second opposition in which he studied the planet4 ,he called it the ,nix ,olympica1 showing that he recognized in it a cousinship to the polar snows4 ,yet it lay in latitude #bj north1 longitude#a #aca1 in the midst of the ochre stretches of that part of the disk4 ,it was a small roundish white speck of not more than two thirds the diameter of the polar cap4 ,reseen by him in #ahha1 it failed to appear at subsequent oppositions and was not caught again until #ahhh4 ,then once more it vanished1 not to be detected anew till many years after at ,flagstaff1 coming out rather surprisingly in #aijc4 ,it showed1 however1 in the same place as before2 so that its position but not its existence is permanent4 ,a similar but smaller patch was apparent to ,schiaparelli at the same opposition of #ahgi4 ,this one which he styled the ,nix ,atlantica lay between the ,thoth and the ,syrtis ,major4 ,it was about half the size of the ,nix ,olympica and has never since been seen1 though it should have been had it continued to be what it then was4 ,illustration3 ,white in ,elysium4 ,on the other hand1 phenomena of the sort undetected of ,schiaparelli have been remarked at ,flagstaff4 ,on ,may #ah1 #aija1 ,i was suddenly struck by the singular whiteness of the southeast corner of ,elysium where that region bordered the ,trivium4 ,elysium has a way of being bright but not with such startling intensity as this spot presented nor in so restricted an area as was here the case4 ,the spot was so much whiter than anything ,i had ever previously seen outside the polar caps that it arrested my attention at once4 ,and this the more that ,i had observed this same part of the planet the day before and perceived nothing out of the ordinary4 ,once detected1 however1 the spot continued visible4 ,the next day it was there with equal conspicuousness1 and now thrust an arm across the ,cerberus1 entirely obliterating the canal for the space of several degrees4 ,in this salience it remained day after day till the region passed from sight1 to reappear with it six weeks later when the region again rounded into view4 ,the hour of the ,martian day seemed to make no difference in its visibility4 ,it was seen from early morning till ,martian afternoon1 as late as the phase permitted4 ,clearly there was nothing diurnal about its revealing1 and it lasted for at least three months and a half1 until the planet got so far away that observations were discontinued4 ,it was to all appearances and intents snow4 ,but now comes the singular fact about it4 ,it lay within ten degrees of the equator and showed from the end of ,june to the latter part of ,august4 ,to our ideas there could be no more inopportune place or time for such an exhibition4 ,for it cannot have been due to a snow-capped peak1 as we know for certain that there are no mountains in this1 or in any other1 part of the planet4 ,besides1 it had not appeared in previous ,martian years2 which it infallibly would have done had it been a peak4 ,indeed1 it baffles explanation beyond any ,martian phenomenon known to me4 ,it seems directly to contradict every other detail presented by the disk4 ,the phenomenon is thus unique in kind2 it is not1 however1 unique as a specimen of its kind4 ,the eastern coast of ,aeria where that region borders the ,syrtis ,major is prone to a brilliance of the same sort4 ,it is a narrow belt of country that shows thus1 nothing but the coastline itself1 but this for a considerable distance stretching several hundred miles in length4 ,it has stood out saliently bright now at every opposition which ,i have observed1 beginning with #ahid4 ,sometimes it has been described in the notes as bright simply1 sometimes as white1 and once1 in #aija1 as glistening at one point like ice4 ,yet when upon the terminator it has never stood forth as a mountain range should have done to declare its character4 ,it has been evident regardless apparently of the ,martian season4 ,in #ahid it was bright from ,october #be to ,january #af 7,martian chronology72 in #ahif1 from ,december #bb to ,january #g2 in #aija1 from ,july #ac to the #aeth2 in #aijc1 at about the same date and so in #aije4 ,it was whitest during the latter oppositions1 showing that the effect is most marked in its midsummer4 ,all of the above instances of extra-polar white have been located within the tropics4 ,examples of the same thing1 however1 occur in the north temperate zone4 ,tempe1 a region just to the west of the ,mare ,acidalium1 is exceedingly given to showing a small white spot close upon the ,mare's border in latitude #ej north4 ,this spot1 too1 on occasion glitters as it were with ice4 ,it is also at times very small4 ,so that whereas much of ,tempe is by nature bright but a small kernel of it is dazzling4 ,the list might be easily extended from the record book4 ,thus on ,march #a and #b1 #aijc1 the disk showed speckled with minute white spots1 one in ,arcadia in latitude #da north1 one in ,tharsis near the equator1 a third just north of the ,phoenix ,lucus in #aj south1 and a fourth1 the ,nix ,olympica1 and on ,april #aa1 a glittering pin-point starred like a diamond the centre of the ,pons ,hectoris4 ,on both these occasions the ,martian season was summer2 ,july #i for the latter1 ,june #ba for the former date4 ,illustration3 ,white in the ,pons ,hectoris4 ,as one approaches the north pole spots of like character become more numerous4 ,especially are such visible north of the ,mare ,acidalium in the arctic region thereabout1 from #fc to #ge north4 ,from so widespread a set of instances the only explanation which seems to fit the phenomena is that the mean temperature of ,mars is low1 not very much above freezing1 and that whatever causes a local fall in the temperature results in hoar-frost4 ,such an explanation accords well with the distance of the planet from the sun and the thinness of its atmosphere4 ,at the same time it shows that the mean temperature over the greater part of the planet the greater part of the time is above the freezing-point and that consequently it is no bar to vegetation of a suitable sort4 ,that the hoar-frost should be found even at the equator may perhaps be due to the very thinness of the air-covering of ,mars1 which would tend to make the actual insolation more of a factor than it is with us1 and by the great length of the ,martian seasons4 ,in midsummer the greatest insolation occurs in the arctic and temperate1 not in the tropic regions2 on the other hand1 an atmosphere tends to accumulate heat for the tropics4 ,with us the latter factor is prepotent2 it would be less effective on ,mars4 ,then again the double duration of summer would tend to emphasize insolation as the important factor in the matter4 ,but it is possible that greater deposition plays a part in the matter4 ,on earth the rainfall is greatest near the equator and something of the sort may be true of the zones of moisture on ,mars4 ,that the most striking spots are found to the west of large dark areas may in this connection have a meaning inasmuch as1 such regions being vegetation-covered1 the air over them is probably more moisture-laden4 ,one point about the position of the spots is of moment3 they have all been found in the northern hemisphere or within ten degrees of it in the southern equatorial region4 ,this seems at first a question of hemispheres2 but when we consider that the light areas of the surface are chiefly in the boreal hemisphere and in the south tropic belt1 we perceive that it may be rather the character of the surface there than the particular hemisphere in the abstract that is decisive in the matter4 ,nevertheless1 the austral hemisphere is the hemisphere of extremes1 possessing a shorter1 hotter summer and a longer1 colder winter than its antipodes4 ,this would not favor sporadic small depositions of frost in summer so much as would a climate of a more mean temperature4 ,from the relative lack of atmospheric covering over the planet we should expect the nights to prove decidedly cool1 while the days were fairly warm4 ,of this we have perhaps evidence in a singular aspect shown by the ,mare ,acidalium in ,june1 #aijc4 ,the account of it in the ,annals reads thus3 8,on ,may #bb an interesting and curious phenomenon presented itself4 ,on that day1 so soon as the ,mare ,acidalium had well rounded the terminator on to the disk1 at #ceb1 the whole of its central part showed white1 the edges of the marking alone remaining as a shell to this brilliant core4 ,so striking was the effect that beside appearing in the drawing it found echo in the notes4 ,the next day no mention is made of it1 and a drawing made under #bj shows the ,mare as usual and the bright spot in ,tempe in its customary place4 ,neither was anything of the sort noticed on the #bdth and #beth4 ,but on the #bfth1 the day of the projection 7upon the terminator71 the effect of the #bc;d reappeared1 the longitude of the centre being #ccb4 ,fortunately on that day a further drawing was secured which enabled its subsequent behavior to be followed4 ,made three hours later than the other1 the longitude of the centre being #ac1 this drawing shows the ,mare well on the disk1 its whole area as dark as usual and with ,tempe bright to the right of it toward the terminator4 ,the terminator in question was the sunrise one1 and we are offered two suppositions in explanation of the phenomenon3 either the white was due to a morning deposition of hoar-frost which dissipated as the sun got up1 or obliquity rendered some superficial deposit visible which more vertical vision hid4 ,that the former inference is the more probable seems hinted at by the simultaneous appearance from the #aith to the #bfth of other areas of white between the ,mare and the pole4 ,may #bf was #hh days after the northern summer solstice1 and corresponded to ,july #ca on the earth40 ,annals1 ,volume ,,iii1 #efd4 ,in this connection mention may pertinently be made of ,schiaparelli's repeated observation of regions that whiten with obliquity1 a proclivity to which he particularly noticed ,hellas and certain #8islands' in the ,mare ,erythraeum to be prone4 ,here as with the ,mare ,acidalium we certainly seem to be envisaging cases of matutinal frost melted by midday under the sun's rays4 ----- ,footnote #a3 ,martian longitudes are now reckoned from the ,fastigium ,aryn1 the mythologic cupola of the world1 a spot easy of recognition because making the tongue in the jaws of the ,sabaeus ,sinus4 ,it further commends itself because of lying within a degree of the equator4 ,the longitudes are reckoned thence westward all the way round1 or to #cfj4 ,,chapter ,,viii ,,climate ,,and ,,weather ,in gazing at the successive phases presented by the polar caps as their annual history unrolls itself to view1 beginning with vast white cloaks that in winter hide so effectively the planet's shoulders1 to little round knobs that in summer sit like guardsmen's caps more or less askew upon the poles1 the bodily eye sees only the glisten of far-off snow4 ,the mind's eye1 however1 perceives something more3 the conviction they carry of the presence of an atmosphere surrounding the planet4 ,elusive as water vapor is to sight for its transparency and to spectroscopic determination for its earthly omnipresence1 recognition of its existence elsewhere by deduction raises such reasoning at once to a more conspicuous plane than it might otherwise assume4 ,especially is this true where the deduction is itself conclusive1 as is here the case4 ,for it depends on phenomena not its own1 but which are in their turn dependent on it4 ,we are not even beholden to any knowledge of the substance composing the caps for the fundamental inference that an atmosphere surrounds them4 ,whatever that substance were1 the fact that the caps dissipate and reform shows us with absolute certainty that they pass into the gaseous state1 to be later solidified afresh4 ,this gas constitutes of itself an atmosphere2 while another phenomenon1 to wit1 their blue girdles as they melt1 affirming their substance to be snow and ice1 enables us to precise the fact that this gas is water vapor4 ,from such premise given us by the polar caps we are able to infer much more by the help of the kinetic theory of gases4 ,but the speed of parting by a planet with its gases is conditioned by the mean speed of each gas4 ,water vapor will1 therefore1 go before nitrogen1 oxygen or carbonic acid gas4 ,if1 then1 we find it present over the surface of a planet we are assured of the possibility that the other three may be there too1 and from the similarity of matter in space strong reason to suspect that they actually are4 ,corroborative evidence of the accuracy of the deduction as to the presence of a ,martian air is shown in several other ways2 in the existence of clouds to begin with4 ,rare as they are1 these certainly float at times over parts of the planet1 although it is doubtful whether they can then be seen4 ,fortunately for assurance we have other ways of ascertaining their presence than that of obscuration4 ,nor is it of account to the argument that they should be few and far between1 as they unquestionably are4 ,one single instance of such mediumistic support is enough to support the theory of a medium2 and that instance has been more than once observed4 ,direct evidence of atmosphere is further forthcoming in the limb-light4 ,this phenomenon might be described as a brilliant obscuration4 ,it is a circlet of illumination that swamps the features as they near the full edge of the disk1 the limb of the planet as it is called4 ,obliteration of the sort is evident1 more or less markedly1 at all times1 and is not due to foreshortening1 as the broadest areas are affected4 ,the fading out of the detail at the limb suggests nothing so much as a veil drawn between us and it1 lighter in tint than what it covers4 ,such a veil can be none other than air or the haze and cloud that air supports4 ,from its effect1 impartial in place and partial in character1 cloud is inadmissible as a cause and we are left with air charged with dust or vapor in explanation4 ,obscuration due to it should prove most dense at the limb1 since there the eye has to penetrate a greater depth of it2 just as on the earth our own air gives azure dimness to the distance in deepened tinting as the mountains lie remote4 ,another bit of evidence lies in the apparent detection of a twilight arc4 ,in #ahid measures made of the polar and equatorial diameters of the planet showed certain systematic residuals left after all known corrections had been applied4 ,the only thing which would account for them was the supposition that a twilight arc had been unconsciously seen and as unconsciously measured4 ,in delicate quantities of the sort too great reliance cannot be put1 but if the residuals be not referable to other cause they give us not only further evidence of an atmosphere1 but at the same time our only hint of that atmosphere's extent4 ,from them it would seem that the air must be rare1 not more than about four inches of barometric pressure1 as we reckon it1 and probably less2 a thin1 high air more rarefied than prevails upon our highest mountain tops4 ,corroborative of this is the aspect of the planet4 ,from the general look of the disk a scant covering of air is inferable4 ,for one of the striking things about the planet's features is their patent exposure to our sight4 ,except in the winter time of its hemisphere or in the spring after the greatest melting of the polar cap1 nothing seems to stand in our way of an uninterrupted view of the surface1 whether in the arctic1 temperate1 or tropic zones4 ,from the openness of its expression1 however1 too much case should not be made as we really know but little of how an atmosphere-enshrouded planet would look4 ,we find no difficulty in seeing objects a hundred miles away across the surface of the earth and yet the thickness of the air strata in such horizontal traversing is many fold what it is when we look directly up4 ,it is also out of all proportion laden with dust and smoke4 ,in the purer regions of the earth1 a clear air imposes but little bar to sight1 and conjures up far things startlingly distinct4 ,nevertheless1 every evidence points to a thin air upon ,mars3 a priori reasoning1 indirect deduction and direct sight4 ,now1 from a thinness of atmosphere it would follow1 other things equal1 that the climate was cold4 ,about this there has been much question1 but less of answering reply4 ,from the distance of the planet from the sun it is certain less heat is received by it than falls upon the earth in something like the ratio of one to two4 ,but that the amount effective is as the amount received is far from sure4 ,the available heat is much affected by the manner of its reception4 ,a blanket of air acts like the glass of a conservatory1 letting the light rays in1 but hindering the heat rays out4 ,the light rays falling on the ground or the air are transformed into heat rays that1 finding the return journey less easy1 are consequently trapped4 ,all substances are thus calorifiers1 but water vapor is many times more potent than ordinary air to heat-ensnaring4 ,a humid air has a hothouse tang to it most perceptible4 ,now1 what the relative percentage of water vapor in the ,martian atmosphere may be we do not know4 ,the thinness of the ,martian air has caused it to be likened to that upon our highest mountain peaks which are in large part covered with perpetual snow4 ,but the comparison is not well founded4 ,a peak differs materially from a plateau in the countenance it gives to the heat falling upon it4 ,on a plateau each warmed acre of ground helps the retention of heat by its neighbor2 while in addition to being destitute of side support the higher winds generated about an isolated peak blow its own caloric away4 ,still less does any analogy hold between the two when the plateau is a world-wide one4 ,from these considerations it is evident glosses are possible upon the bald idea of a much lower temperature prevailing on the ,martian surface than on the earth's4 ,doubtless the theoretic cold has been greatly overdone4 ,reversely1 recent observations tend to lower the apparent temperature disclosed by the features of the disk1 and between the rising of the theoretic and the falling of the observed we are left with a very reasonable compromise and reconcilement as the result4 ,the various look and behavior of the surface of ,mars point to a mean temperature colder than that of the earth1 but above the freezing-point of water2 for regions1 at least1 outside of the polar caps and during all but the winter months4 ,except at certain special spots1 and possibly even there1 frost is unknown at all times within the tropics and except in winter in temperate latitudes4 ,these anomalous localities1 mentioned in the preceding chapter1 may be said to be the exceptions that prove the rule of general non-glaciation4 ,for if they be snow1 they stand witness to its absence elsewhere upon the disk1 and if they are not1 they testify the more emphatically to the same effect4 ,as between different parts of the surface1 the tilt of the ,martian axis and the greater length of the ,martian seasons1 the one the same as1 the other the double of1 our own1 tend to an accentuation of the heat in the temperate and arctic or antarctic zones4 ,the greatest insolation on earth is not1 as we might suppose1 at the equator1 but at the parallels of #dc4e north and south2 even the poles themselves receiving a quarter as much heat again on midsummer day as ever falls to the lot of the line4 ,this broad physical fact is equally true of ,mars1 while in the matter of consecutive exposure ,mars in summer outdoes the earth4 ,for the longer the seasons1 the more nearly does the effective heat approach the received amount4 ,thus both on the score of heat received and of heat husbanded these zones must be relatively warm4 ,and this shows itself in the look of the surface4 ,in summer it is clearly warmer within the polar regions than is the case on earth1 to judge by the effect4 ,in winter the cold is doubtless proportionately severe4 ,for the diurnal range of temperature we have less data4 ,there is evidence pointing to chilly nights1 but it is meagre1 and we are left to fall back on the cold of our deserts at night for analogic condition of the state of things over the ,martian desert levels after the sun goes down4 ,if we are uncertain of the precise character of the ,martian climate1 we know on the other hand a good deal about the ,martian weather4 ,a pleasing absence of it over much of the planet distinguishes ,martian conditions from our own4 ,that we can scan the surface as we do without practical interruption day in and day out proves the weather over it to be permanently fair4 ,in fact a clear sky1 except in winter1 and in many places even then1 is not only the rule1 but the rule almost without exceptions4 ,in the early days of ,martian study cases of obscuration were recorded from time to time by observers1 in which portions of the disk were changed or hidden as if clouds were veiling them from view4 ,more modern observations fail to support this deduction1 partly by absence of instances1 partly by other explanation of the facts4 ,certainly the recorded instances are very rare4 ,indeed1 occasions of the sort must to any ,martians be events1 since only one possible example has presented itself to me during the course of my observations1 extending more or less over eleven years4 ,even in this case there was no obliteration1 though a certain whiteness overspread an area near the equator temporarily4 ,position seemed to point to its identity with a cloud which made its appearance about that time upon the terminator1 and lasted for some thirty-six hours4 ,the cloud1 however1 showed evidence of being1 not the kind with which we are familiar1 but a dust-storm1 in keeping1 indeed1 with the desert region 7,chryse7 in which it originated4 ,with the exception of sporadic disturbance of the sort the whole surface of the planet outside the immediate vicinity of the polar caps seems free from cloud or mist and to lie perpetually unveiled to space4 ,in the neighborhood of the caps1 however1 and especially round about their edge1 a very distinct pearly appearance is presented during the months at which the cap is at its maximum1 or in other words1 in the depth of its winter4 ,of a dull white hue and indefinite contour the phenomenon suggests cloud4 ,where it lies spread no markings are visible2 an absence explicable by obscuration due an interposed medium1 but equally well by seasonal non-existence of the markings themselves1 which from the general behavior of these markings we know to be to some extent certainly the fact4 ,of the regions where the effect is noticeable1 ,hellas is the most striking4 ,so conspicuously white during the winter of the southern hemisphere as to have been often mistaken for the polar cap1 its ghost shows thus almost regularly every ,martian year4 ,what is as suggestive as it is striking1 the blanching is confined to the solid circle constituting ,hellas and does not extend into the dark regions by which it is circumscribed4 ,hellas is as self-contained when thus powdered as when1 in its normal ochre or abnormal red1 it stretches like a broad buckler across the body of the disk4 ,that the land there lies at a higher level than its surroundings is pretty certain1 but that the difference can amount to enough to explain its silveriness as ice is improbable4 ,in latitude ,hellas is distinctly temperate1 lying between the parallels of #ee and #cj2 but on ,mars this is no warrant of a like climate4 ,again1 though close on the south to what constitutes the polar cap1 it does not strictly form part of that cap1 but occupies both in position and in kind a something intermediary between the frost-bound regions of periodic snow and the warmer ones of perpetual sunshine4 ,it seems to be afflicted with the winter weather of the north of ,europe1 and to owe its pearly look at such times to the same cloud canopy that then distressingly covers those inclement lands4 ,similar in behavior to it is the long chain of so-called islands that1 beginning southwest of ,thaumasia1 runs thence westward even to the eastern edge of ,hellas4 ,these belt the planet in a west-northwesterly direction by a strip of territory from ten to fifteen degrees wide1 the medial line of which begins at #ee south and ends in about #dj4 ,they are parted from the main bright areas by blue-green #8seas' of about the same width as themselves1 the ,mare ,sirenum1 the ,mare ,cimmerium and ,mare ,tyrrhenum4 ,these #8seas' the white that covers the #8islands' never crosses2 though the continent1 as we may call it for convenience1 descends at the east to #cj south4 ,since the #8seas' are not seas1 the cause which might bound the snow1 were they such1 cannot be the cause here4 ,nevertheless1 they have an effect of some sort on the isothermal lines as is shown not only by latitudinal comparison with the state of things in ,hellas1 but with that in ,thaumasia as well4 ,for #cj south is also the limit apparently of the white on ,thaumasia1 where ochre desert stretches ten degrees farther south still2 the region in its southern part being white-mantled1 in its northern part not4 ,here again1 then1 the ochre areas make exception to what affects the blue-green ones4 ,clearly the blue-green regions temper the action of what gives them wintry cloak4 ,but why they should do this is not easy to explain on any supposition terrestrial or marine4 ,bodies of water tend to foster the formation of clouds2 so1 less markedly1 do areas of vegetation4 ,neither the old ideas1 then1 nor the new lend themselves in explanation4 ,it may be that while we here seem to be envisaging cloud we are in reality looking at hoar-frost4 ,on the other hand1 light cloud would show less1 superposed over a dark background1 than over an ochre one2 and this1 the simplest of all explanations1 may be the true one4 ,it is facts like these that intrigue us in the study of the ,martian surface by revealing conditions which render offhand analogy with the earth unsafe4 ,indeed1 we are more sure of some things which appear too strange to be true than of others so simple on their face as to enlist belief4 ,among the most difficult and perplexing are meteorological problems like the above4 ,here we can only say provisionally that while cloud best answers to the appearance1 frost best fits the cause4 ,for vegetation might melt frost1 yet not dissipate cloud4 ,by raising our conception of the mean temperature the facts can1 however1 be reconciled and this is probably the solution of the difficulty after all4 ,as we saw in the annual history of the polar caps a dimness somewhat different affects the northern cap in ,may and ,june4 ,after the melting of the cap is well under way a haziness sets in along its edge which befuddles its outline and effectually hides what is going on within it4 ,when at last the screen clears away the cap is found to be reduced to its least dimensions4 ,such obstructing sheet looks to be more of the nature of mist caused by the excessive melting of the cap4 ,unfortunately1 there are here no patches of blue-green to test a possible partiality in its behavior over such tracts2 nor has similar action ever yet been remarked in the case of the cap of the southern hemisphere4 ,regular recurrence at the appropriate season of the planet's year1 together with extensive action at the time1 takes this springtide mist to some extent out of the domain of weather into that of climate4 ,for it prevails all round the cap and repeats itself in place as each fresh spring comes on4 ,at least it has done so for the past three oppositions at which it has been possible to observe well the arctic zones4 ,it is thus both general in its application and fixed in its behavior4 ,nevertheless1 it betrays something of the fickleness which characterizes that more inconstant thing3 weather4 ,for it comes and goes1 one thinks for good1 only to find it there again some days later4 ,not less captious is the meteorologic action shown in the making of the new polar cap4 ,when the northern one starts to form1 vast areas of frost are deposited in a single night4 ,these1 however1 are not permanent4 ,the ground thus covered is during the next few days again partially laid bare4 ,then a new fall occurs1 hiding the surface a little more completely than before1 and the lost domain is more than regained4 ,by such wavelike advance and recession the tide of frost creeps over and submerges the arctic regions as the late summer passes into the autumn4 ,in this alternate coming and going with succeeding days1 we have an unsteadfastness of action most fittingly paralleled by our own weather4 ,it would seem that local causes there as here are superposed upon the orderly progress of the seasons and though at the on-coming of the autumn the cold is steadily gathering strength1 nevertheless warm days occur now and then to stay its hand1 only to be succeeded in their turn by frosts more biting than before4 ,even on ,mars nothing in the way of weather is absolutely predicable but impredicability4 ,,chapter ,,ix ,,mountains ,,and ,,cloud ,in all ways but one our scrutiny of the planet is confined to such view as we might get of it from the car of a balloon poised above it in space2 from which disadvantage-point we should see the surface only as a map spread out below us1 a matter of but two dimensions4 ,the exception consists in the observation of what are called projections2 irregularities visible when the disk is gibbous upon that edge of the planet where the light fades off4 ,striking phenomena in themselves they are of particular value for what may be deduced from them4 ,for by them we are afforded our only opportunity of gaining knowledge of the surface other than in plan and thus of determining between peak1 plateau1 or plain that to a bird's-eye view alike lie flattened out to one dead level4 ,it might at first be thought that our best chance of noting any elevations or depressions of the ,martian surface lay in catching that surface in profile1 by scanning the bright edge of it which stands sharp-cut against the sky and is called the limb4 ,for this is practically what we do on earth when we mark a mountain against the horizon and measure its height by triangulation4 ,unfortunately the method fails in the case of ,mars because of the great distance we are away4 ,unless the planet were distinctly more generously equipped than the earth in the matter of mountains1 nothing could be hoped from so forthright an envisaging4 ,so relatively insignificant to the size of its globe is the relief of the earth's surface that an orange skin would seem grossly rough by comparison4 ,the same proves true for ,mars4 ,with the greatest magnification we can produce1 the ,martian limb still appears perfectly smooth4 ,luckily1 while direct vision is thus impossible1 oblique illumination enables us to get an insight into the character of the surface we had otherwise been denied4 ,when mountains or valleys chance to lie upon the boundary of light and darkness1 the rim of the disk known as the terminator in contradistinction to the limb where the surface itself comes to an end1 they make their presence evident through an indirect species of magnification1 the elongate effect of oblique lighting4 ,with a practical instance of it every one is familiar who has walked by night along a road imperfectly starred at intervals by electric lights4 ,startled between posts by what seemed deep holes and high furrows he has involuntarily imitated a spavined horse for fear of stubbing his toes1 only to encounter when his foot fell a surface on contact surprisingly smooth4 ,the slant illumination by lengthening the shadows had painfully deceived him into exaggerated inference of irregularity4 ,what proves disturbing to a wayfarer misguided by arc lights is made to do the eye service when it comes to planetary interpretation4 ,on the boundary of light and shade1 those parts of the surface where it is sunrise or sunset upon the planet1 the sun's rays fall so athwartwise as to throw enormous shadows from quite small elevations to an eye so placed as to view the surface with anything approaching perpendicularity4 ,a mountain mass there will thus proclaim itself by protracted profile upon the plain in hundredfold magnification4 ,similarly a peak there will advertise its height by catching the coming or holding the lingering light at many times the distance of its own elevation away from the night side of the planet4 ,here1 if anywhere1 then1 could mountains be expected to disclose themselves1 and here1 when existent1 they have as a matter of fact been found4 ,our own moon offers us the first and easiest example of such vicariously visible relief4 ,when the moon is near the quarter1 and for three or four days on either side of that1 a keen eye can usually detect one or more knobs1 like warts1 projecting from its terminator1 easily distinguished from the limb both by reason of being less bright and of being bounded by a semi-ellipse instead of a semicircle4 ,if a telescope or even an opera-glass be substituted for the eye1 it is possible to see what causes them2 the knob resolves itself into the illuminated rim of a crater separated from the main body of the visible moon by the seemingly black void of space4 ,the peak has caught the sunlight1 while its foot and the country between it and the illuminated surface still lies shrouded in shadow4 ,from measurement of the distance the sun-tipped peak seems to stand aloof from the line where the plain itself is touched by the light1 the height of it above that plain may be calculated4 ,in this way have been found the heights of the mountains of the moon4 ,incidentally1 brain outstrips brawn4 ,for pinnacles no ,lunarian could scale1 both for their precipitous inaccessibility and their loftiness1 man has measured without so much as setting foot upon their globe4 ,at each lunar sunrise and again at lunar sunset these old crater walls show their crescent coronets tipped the reverse way2 and peaks higher than the ,himalayas make gigantic gnomons of themselves with hands outstretched to grasp the plains4 ,in this manner a lunar peak of fifteen thousand feet shows its presence to the unaided eye4 ,with so much for starting-point we can calculate how low an elevation could similarly be made out on ,mars under a like phase illumination4 ,now1 in spheres of different diameters the distance out from the terminator for a given height is as the square root of the diameter4 ,mars has about twice the size of the ,moon4 ,in consequence1 if we saw the planet at the same distance off as the ,moon1 the height of a peak upon it sufficient to cast an equal shadow or be seen at an equal separation from the terminator need be but two thirds as high4 ,to see it thus equidistant a power of #bej or #cjj is necessary1 dependent on the opposition4 ,twice this power may at times be used1 and by the same reasoning this would reduce the height sufficient to show by four or to something like #bejj feet4 ,this1 then1 would be the theoretic limit of the visible1 a limit needing to be somewhat increased because of the imperfection of our air4 ,having found thus what should be visible on ,mars we turn now to see what is4 ,at once we find ourselves confronted with a very unlunar state of things4 ,common upon the face of the ,moon1 excrescences of the terminator are rare on ,mars4 ,the first ever seen was detected by a visitor at the ,lick ,observatory in #ahhh4 ,since then they have been repeatedly noticed both at the ,lick and elsewhere4 ,but although observers are now on the watch for them1 they are not very frequently chronicled because not of everyday occurrence4 ,much depends upon the opposition2 some approaches of the planet proving more prolific of them than others4 ,how rare they are1 however1 may be gathered from the fact that the last three oppositions have disclosed but one apiece4 ,an account of the great projection of ,may #be1 #aijc1 will give an idea of the extent and interest of the phenomenon and will serve to show to what cause we must attribute all such that have been visible on ,mars1 for the behavior of this one was typical of the class4 ,illustration3 ,projection on terminator4 ,about half past eight o'clock in the evening of ,may #bf1 #aijc1 ,mr4 ,v4 ,m4 ,slipher1 astronomer at ,flagstaff1 shortly after taking over the telescope then directed upon ,mars1 suddenly noticed a large projection about halfway up the terminator of the planet4 ,he at once sent word of the fact and the observatory staff turned out to see it1 for a projection has for workers on ,mars the like interest that a new comet possesses for astronomers generally4 ,in this case the phenomenon was specially potent in that it was the first to be detected that year4 ,its singularity was amply seconded by its size4 ,for it was very large1 its extent both in length and height being excessive4 ,when ,i first saw it1 the projection consisted of an oval patch of light1 a little to the north of the centre of the phase ellipse lying parallel to the terminator but parted from it by darkness to the extent of half the projection's own width4 ,it made thus not simply an excrescence but a detached islet of light4 ,it was easily seen by all those present and was carefully studied from that time on by ,mr4 ,slipher and me4 ,both of us made drawings of it alternately at intervals1 as well as micrometer measures of its position4 ,next to its great size1 the most striking feature about it was its color4 ,this1 instead of being white or whitish1 was ochre orange1 a hue closely assimilated to the tint of the subjacent parts of the disk1 which was the region known as ,chryse4 ,this distinctive complexion it kept throughout the period of its apparition4 ,at the same time ,baltia1 a region to the north of it and synchronously visible close upon the terminator1 showed whitish4 ,the seeing was good enough to disclose the ,phison and ,euphrates double1 the power a magnification of #caj and the aperture the full aperture of the #bd-;inch objective4 ,from the time it was first seen the detached patch of light crept in toward the disk1 the illuminated body of the planet4 ,four minutes after ,i noted it the dark space separating it from the nearest point of the terminator had sensibly lessened4 ,so it continued1 with some fluctuations intrinsic to the atmospheric difficulties of observations generally and to the smallness of the object itself1 to become gradually less and less salient4 ,it lasted for about forty minutes from the moment it had first appeared to ,mr4 ,slipher and then passed from sight to leave the edge of the planet smooth and commonplace again4 ,the measures made on it showed that it lay when first seen in longitude #ci4g1 latitude #ah4e north1 and that its highest point stood seventeen miles above the surface of the planet4 ,it was three hundred miles long4 ,these are my own figures1 from which ,mr4 ,slipher's do not substantially differ4 ,the return of the part of the planet where it had been seen was eagerly awaited the night after by both observers1 to see if it would bring the projection with it4 ,for only once a day is the same region of ,mars similarly presented4 ,but in order not to miss the projection1 should it be ahead of time1 observations were begun before it was due4 ,shortly after they were started1 there appeared higher up the terminator and therefore farther north than had been the case the night before1 a small projection4 ,it was with difficulty made out and its position measured4 ,without careful watching it must have been missed altogether4 ,as it was1 it differed in every respect from that of the preceding day4 ,it was not nearly so high1 not nearly so large1 and lay in a different place on the planet1 being now in longitude #ca4g1 latitude #be4e4 ,either the two1 therefore1 were totally different things or the projection had moved in the elapsed interval of time over seven degrees of latitude and eight degrees of longitude1 a distance of three hundred and ninety miles in twenty-four hours4 ,where the previous projection had been nothing showed4 ,on the following night1 ,may #bh1 no trace of anything unusual could be seen anywhere4 ,we are now concerned to inquire to what this series of appearances could have been due4 ,the first observers of projections on ,mars had unhesitatingly attributed them to the same cause that produces projections on the ,moon1 to wit1 mountains4 ,such they were held to be in ,france and at the ,lick4 ,this view1 however1 was in #ahib disputed by ,w4 ,h4 ,pickering who considered them to be not mountains1 but cloud4 ,and this view was strongly supported by ,a4 ,e4 ,douglass in a discussion of a large number of them observed in #ahid at ,flagstaff4 ,the mountain theory of their generation was finally shown to be untenable and their ascription to cloud conclusively proved to be the correct solution by the observations of a remarkable one made in ,december1 #aijj1 and the careful study to which by the writer they were subjected4 ,we shall now explain how this was done and we will begin by pointing out that the fact that only a single specimen of the phenomenon was visible at each of the three oppositions of #aijj1 #aijc1 and #aije was itself conclusive1 rightly viewed1 of their non-mountainous character4 ,this conclusion follows at once from the isolateness of the phenomenon4 ,for a mountain cannot change its place4 ,now1 the shift in the aspect presented by the planet's disk from one night to the next is not sufficient to alter perceptibly the appearance shown by anything upon its edge on the two occasions4 ,if1 then1 a peak stood out upon it one evening1 the peak should again show salient when the region reached the same position upon the succeeding night4 ,that nothing then was seen where something had previously been visible proved the phenomenon not that of a mountain peak1 since what produced the projection was clearly not fixed in place and therefore not attached to the soil4 ,now the only other thing capable of catching the light before it reached the surface would be something suspended in the air1 that is1 a cloud4 ,deduction1 therefore1 from the rarity of the phenomenon alone showed that the projections must be clouds4 ,their behavior in detail entirely corroborates this deduction from their intermittence4 ,such was shown by the action of the projection of ,december #f1 #aijj1 as set forth in a paper before the ,american ,philosophical ,society and such again by that of the one of ,may #bf1 #aijc1 as we shall now note4 ,to begin with1 we notice that the projection seen on ,may #bf was not found either in situ or in size on ,may #bg and had wholly vanished on ,may #bh1 though the seeing was substantially the same if not better on the two nights succeeding that of its original detection4 ,hence in its own instance this projection proved an alibi irreconcilable with the character of a mountain mass4 ,but it did more4 ,it not only was not on the second evening what and where it had been on the first1 but the remains of it visible on the second occasion showed clearly that it had moved in the meantime4 ,furthermore it was disappearing as it went1 for it was very much smaller after the lapse of twenty-four hours4 ,the something that caused it was not only not attached to the soil1 but was moving and dissipating as it moved4 ,only one class of bodies known to us can account for these metamorphoses and that is3 cloud4 ,but what kind of cloud are we to conceive it to be8 ,our ordinary vapor clouds are whitish and this would be still more their color could they be looked at from above4 ,the ,martian cloud was not white but tawny1 of the tint exhibited by a cloud of dust4 ,nor could this color have very well been lent it by its sunrise position1 for other places equally situated to be tinged by the hues of that time of day1 ,baltia to wit1 showed distinctly white4 ,so that we must suppose it to be what it looked1 a something of the soil1 not beholden to atmospheric tinting for its hue2 a vast dust-cloud traveling slowly over the desert and settling slowly again to the ground4 ,precisely the same general course of drifting disappearance was taken by the projection of ,december #g and #h1 #aijj4 ,and this1 too1 stood an unique apparition in the annals of its opposition4 ,clouds1 then1 and not mountains are the explanation of the projections on ,mars1 differing thus completely from the lunar ones4 ,,chapter ,x ,,the ,,blue-,,green ,,areas ,descending now equatorwards from the polar regions1 and their in part paleocrystic1 in part periodic1 coating of ice1 we come out upon the general uncovered expanse of the planet which in winter comprises relatively less surface than on ,earth1 but in summer relatively more4 ,forty degrees and eighty-six degrees may be taken as the mean hiemal and stival limits respectively of the snow on ,mars2 forty-five and seventy-five as those of the ,earth4 ,whatever ground is thus bared of superficial covering on ,mars lies fully exposed to view1 thanks to the absence of obscuring cloud2 and it is at once evident that the terrane is diversified1 patches of blue-green alternating with stretches of reddish ochre4 ,of the two opaline tints the reddish ochre predominates1 fully five eighths of the disk being occupied by it4 ,it was early evident in the study of the surface of ,mars that its ochreish disk was not spotless4 ,huyghens in #afei saw the ,syrtis ,major4 ,from this first fruit of areography dates1 indeed1 the initial recognition of the planet's rotation2 for on noting that the marking changed its place1 he inferred a turning of the planet upon itself in about twenty-four hours4 ,thirteen years later he observed and drew it again and this time in company with the polar cap4 ,again1 after eleven more years1 he depicted it for the third time1 and now so changed because of the different tilt of the planet toward the earth that it may be doubted whether ,huyghens himself recognized it for the same4 ,but that he drew it correctly a globe of ,mars will at once show4 ,from such small beginning did areography progress to the perception of permanent patches of a sombre hue distributed more or less irregularly over the disk4 ,impressing the observers simply as dark at first1 they later came to be recognized as possessing color1 a blue-green1 which contrasted beautifully with the reddish ochre of the rest of the surface4 ,cassini1 ,maraldi1 ,bianchini1 ,herschel1 ,schroeter1 all saw markings which they reproduced4 ,finally1 with ,beer and ,maedler1 came the first attempt at a complete geography4 ,in and out through the ochre was traced the blue2 commonly in long ,mediterraneans of shade1 but here and there in isolated ,caspians of color4 ,with our modern telescopic means the dark patches are easily visible1 the very smallest glass sufficing to disclose them4 ,when thus shown they much resemble in contour the dark patches on the face of the ,moon as seen with the naked eye4 ,now these patches were early taken for lunar seas and received names in keeping with the conception2 as the ,sea of ,serenity1 the ,sea of ,vapors1 and so forth4 ,following the recognition of a like appearance1 like appellatives were given to the ,martian markings2 and the ,mare ,sirenum1 or ,sea of the ,sirens1 the ,mare ,cimmerium1 and others sufficiently proclaim what was thought of them at the time they were thus baptized4 ,indeed1 if a general similarity be any warrant for a generic name they were not at the time ill-termed4 ,for1 common to all three bodies1 the ,earth1 the ,moon1 and the planet ,mars1 is the figuration of their surfaces into light areas and dark4 ,in the ,martian disk1 as in the lunar one1 we seem to be looking at a cartographic presentation of some strange geography suspended in the sky2 the first generic difference between the two being that the chart is done in chiaroscuro for the ,moon1 in color for ,mars4 ,on mundane maps1 we know the dusky washes for oceans2 so on the ,moon it was only natural to consider their counterparts as maria2 and on ,mars as #8seas4' ,nor did the blue-green hue of the ,martian ones detract from the resemblance4 ,but in something other than color these markings are alike4 ,in fact1 color could hardly be excuse for considering the lunar maria what their name implies1 for distinctive tint is lacking in them1 even to the naked eye4 ,it was in form that the likeness lay4 ,their figures were such as our own oceans show2 and allowing for a sisterly contrast amid a sisterly resemblance1 the lunar maria or the ,martian seas might well have been of similar origin to those with which our schoolboy study of atlases had made us familiar4 ,thus did similarity in look suggest similarity in origin1 and intuitive recognition clothe its objects with the same specific name4 ,considerable assumption1 however1 underlay the pleasing simplicity of the correlation on other grounds1 consequent not so much upon any lack of astronomic knowledge as1 curiously1 upon a dearth of knowledge of ourselves4 ,we know how other bodies look to us1 but we ignore how we look to them4 ,it is not so easy to see ourselves as others see us2 for a far view may differ from a near one1 and a matter of inclination greatly alter the result4 ,owing both to distance and to tilt we lack that practical acquaintance with the aspect of our own oceans viewed from above1 necessary to definite predication of their appearance across interplanetary space4 ,our usual idea is that seas show dark1 but it is also quite evident that under some circumstances they appear the contrary4 ,it all depends upon the position of the observer and upon the position of the ,sun4 ,their usual ultramarine may become even as molten brass from indirect reflection2 while on direct mirroring1 they give back the ,sun with such scarce perceptible purloining of splendor as to present a dazzling sheen not to be gazed upon without regret4 ,canopied by a welkin they assume its leaden hue1 while at the same time1 their shores1 less impressionable to borrowed lighting1 show several tints darker than themselves4 ,surfaces so sensitive to illumination hardly admit of more accusable tint than a chameleon4 ,nevertheless1 we are probably justified in our conviction that perpendicularly visaged1 they would on the whole outdo in sombreness land round about them1 and so be evident as dusky patches against a brighter ground4 ,one phenomenon we might with some confidence look to see exhibited by them were they oceans1 and that is the reflected image of the ,sun visible as a burnished glare at a calculable point4 ,specular reflection of the sort was early suggested in the case of ,mars1 and physical ephemerides for the planet registered for many years the precise spot where the starlike image should be sought4 ,but it was never seen4 ,yet not till the marine character of the ,martian seas had been otherwise disproved was the futile quest for it abandoned4 ,indeed1 it was a tacit recognition that our knowledge had advanced when this column in the ephemeris was allowed to lapse4 ,on this general marine ascription doubt was first cast in the case of the ,moon4 ,so soon as the telescope came to be pointed at our satellite1 it was evident that the darker washes were not water surfaces at all1 but very palpably plains4 ,long low ridges of elevation stood out upon them like prairie swells1 which grew in visible relief according to the slanting character of the illumination4 ,cracks or rills1 too1 appeared near their edges and craters showed in their very midst4 ,patently solid they betrayed their constitution not only by diverse topography but by diversified tint4 ,all manner of shades of neutral tone mottled their surface1 from seeming porphyry to chalk4 ,belief perforce departed when the telescope thus pricked the bubble1 evaporating as the water itself had done long before4 ,so much was known before the ,mars' markings were named4 ,nevertheless1 humanity1 true to its instincts1 promptly proceeded to commit again the same mistake1 and1 cheerfully undeterred by the exposure of its errors in the case of the ,moon1 repeated the christening in the case of ,mars4 ,so sure was it of its ground that what it saw was not ground1 that though the particular appellatives of the several seas were constantly altered1 rebaptisms1 while changing the personal1 kept the generic name4 ,dawes' ,ocean1 for example1 later became l',ocean ,newton and later still the ,mare ,erythraeum1 but remained set down as much a sea as before4 ,about thirteen years ago1 however1 what had befallen the seas of the ,moon1 befell those of ,mars3 the loss of their character4 ,it was first recognized through a similar exposure2 but the fact was led up to and might have been realized in consequence of quite a different line of evidence4 ,the initial thing to cast doubt upon the seas being what they seemed to be was the detection of change in their aspect4 ,that the detection was not made much earlier than actually happened shows how a phenomenon may elude observation if scrutiny be not persistent1 and its results from time to time not carefully compared4 ,schiaparelli was the one who first noticed variation in the look of the seas1 and the discovery was as much due to the assiduity with which he followed the planet opposition after opposition as to the keenness with which he scanned it4 ,the noting of change in the blue-green areas constituted1 in fact1 one of the first fruits of systematic study of the planet4 ,change in configuration1 that is1 alteration of area1 preceded in recognition alteration of tint4 ,thus the ,syrtis ,major showed larger to him in #ahgi than it had in #ahgg4 ,this was natural2 difference of degree being a more delicate matter to perceive than its effect upon extent4 ,from change of area his perception went on to change of tone4 ,in his own words1 what he noticed was this3 ,memoria1 ,,vi1 #ahhh1 8,no less certain is it that1 from one opposition to another1 one notices in the seas1 very remarkable alterations of tone4 ,thus the regions called ,mare ,cimmerium1 ,mare ,sirenum1 and ,solis ,lacus1 which during the years #ahgg to #ahgi could be numbered among the most sombre on the planet1 during the succeeding oppositions became less and less black1 and in #ahhh were of a light gray hardly sufficient to render them visible in the oblique position in which all three found themselves4444 ,on the other hand1 at the very same moment1 the ,mare ,acidalium and the ,lacus ,hyperboreus showed very dark2 the latter indeed appeared nearly black1 although seen as tilted as the ,syrtis and the equatorial bays4 ,the condition of the regions called seas is therefore not constant3 so much is unquestionable4 ,perhaps the change produced in them has to do with the season of the planet's year40 ,holding as he did the then prevailing view that the blue-green regions were bodies of water1 he regarded those of intermediate tint as vast marshes or swamps1 and he accounted for change of hue in them as due to inundations and occasions of drying up4 ,in consequence of losing their water1 the seas1 he thought1 had in places become so shallow that the bottom showed through4 ,plausible on the surface1 this theory breaks down so soon as it is subjected to quantitative criticism4 ,for the moment we try to track the water1 we detect the inadequacy of the clew4 ,the enormous areas over which the phenomenon occurs necessitates the establishing an alibi for all the lost water that has gone4 ,drying up on such a scale would mean the removal of many feet of liquid over hundreds of thousands of miles in extent4 ,to produce any such change in appearance as we witness1 even on the supposition that these seas were none too deep to start with1 would involve lowering the level of the water by from five to twenty feet throughout two thirds of the whole surface of the southern hemisphere4 ,this would leave a heap of waters to be accounted for1 bewildering in its immensity4 ,the myriad tons of it must be disposed of2 either by drainage into other regions or by being caught up into the sky4 ,in this emergency it might seem at first as if the polar cap of the opposite hemisphere offered itself as a possible reservoir for the momentarily superfluous fluid4 ,but such hoped-for outlet to the problem is at once closed by the simple fact that when the lightening of the dark regions of the southern hemisphere takes place1 the opposite polar cap has already attained its maximum2 in fact1 has already begun to melt4 ,it1 therefore1 absolutely refuses to lend itself to any such service4 ,this was not known to ,schiaparelli's time1 the observations which have established it1 by recording more completely the history of the cap1 having since been made4 ,indeed1 it was not known even at the time when the writer1 in #ahid1 showed the impossibility of the transfer on other grounds2 to wit1 on the fact of no commensurate concomitant darkening of the surface elsewhere and on the manifest non-complicity1 if not impotency1 of the ,martian atmosphere in the process4 ,the transference of the water to other dark patches in the northern hemisphere fails of sufficiency of explanation because of the limited extent of such areas on that side of the globe2 while the air is quite as incapable of carrying away any such body of liquid1 though the whole of it were at the saturation-point1 not to mention that there exists no sign of the attempt4 ,the reader will find this reasoning set forth in ,mars1 published eleven years ago4 ,he will now note1 from what has been said above about the northern polar cap1 that continued observations since have resulted in opening up another line of proof which has only strengthened the conclusion there reached4 ,illustration3 ,lines in dark area4 ,the coup de grce1 however1 to the old belief was given when the surface of the dark areas was found to be traversed by permanent lines by ,pickering and ,douglass4 ,continued observation showed these lines to be unchangeable in place4 ,now permanent lines cannot exist on bodies of water1 and in consequence the idea that what we looked on there were water surfaces had to be abandoned4 ,thus we now know that the markings on both the ,moon and ,mars which have been called maria are not in reality seas4 ,yet we shall do well still to keep the old-fashioned sonorous names1 ,mare ,erythraeum1 ,mare ,sirenum1 and their fellows1 because it is inconvenient to change2 while1 if we please1 we may see in their consecrated ,latin couching the fit embalming in a dead language of a conception that itself is dead4 ,,chapter ,,xi ,,vegetation ,since closer acquaintance takes from the maria their character of seas1 we are led to inquire again into their constitution4 ,now1 when we set ourselves to consider to what such appearances could be due we note something besides sea1 which forms a large part of our earth's surface1 and would have very much what we suppose the latter's aspect from afar to be1 not only in tone1 but in tint4 ,this something is vegetation4 ,seen from a height and mellowed by atmospheric distance1 great forests lose their green to become themselves ultramarine4 ,to dispossess a previous conception is difficult1 but so soon as we have put the idea of seas out of our heads a vegetal explanation proves to satisfy the phenomena1 even at first glance1 better than water surfaces4 ,in their color1 blue-green1 the dark areas exactly typify the distant look of our own forests2 whereas we are not at all sure that seas would4 ,from color alone we are more justified in deeming them vegetal than marine4 ,but the moment we go farther into the matter the more certain we become of being upon the right road4 ,with increased detection the markings they reveal and the metamorphoses they undergo1 while pointing away from water1 point as directly to vegetation4 ,all the inexplicabilities which the supposition of water involves find instant solution on the theory of vegetal growth4 ,the non-balancing of the areas of shading in their shift from one part of the disk to another1 no longer becomes a circumstance impossible to explain1 but a necessary consequence of their new-found character1 denoting the time necessary for vegetation to sprout4 ,the change of hue of vast areas from blue-green to ochre no longer presupposes the bodily transference of thousands of tons of substance1 but the quiet turning of the leaf under autumnal frosts4 ,even the fact that they occupy those regions most fitted by figure to contain oceans fits in with the same conception4 ,for that the ,martian equivalents of forest and moorland1 tree and grass1 should grow now in the lowest parts of the planet's surface is what might not unreasonably be expected from the very fact of their being low1 since what remained of the water would tend both on the surface and in the air to drain into them4 ,illustration3 ,mare ,erythrum ,martian date4 ,december #cj ,for the change in question to be vegetal it must occur at the proper season of the planet's year4 ,this we must now consider4 ,we have said that ,schiaparelli detected change in the blue-green regions and suspected this change of seasonal affiliation4 ,he inferred this from piecing together the aspects of different seasons of different years as shown in consecutive ,martian oppositions4 ,to mark it actually take place in a single ,martian year came later4 ,in #ahid1 at ,flagstaff1 the southern hemisphere was presented during its late spring and early summer2 it was observed1 too1 for many of our months in succession4 ,during this time the planet was specially well circumstanced for study of the change in that hemisphere1 both by reason of the appositeness of the season and of the unusual size of the disk4 ,advantage was taken of the double event to a recording of the consecutive appearances certain regions underwent1 and the contrasted states thus exhibited were such as clearly to betoken the action of seasonal change4 ,what ,schiaparelli had thus ably inferred from diverse portions of different ,martian years was in this case shown occurring in one and the same semestral cycle4 ,usually the change of hue seems essentially one of tone2 the blue-green fades out1 getting less and less pronounced1 until in extreme cases only ochre is left behind4 ,it acts as if the darker color were superimposed upon the lighter and could be to a greater or less extent removed4 ,this is what ,schiaparelli noted and what was seen in #ahid at ,flagstaff4 ,three views en suite of the chain of changes then observed are shown in ,mars1 the region known as ,hesperia being central in each4 ,comparison of the three discloses a remarkable metamorphosis in that 8promontory10 a rise into visibility by a paling of its complexion4 ,nor is the contrast confined to it2 changes as salient will be noticed in the pictures over the other parts of the disk4 ,there have been instances1 however1 of a metamorphosis so much more strange as to deserve exposition in detail2 one where not tone simply is involved1 but where a quite new tint has surprisingly appeared4 ,illustration3 ,mare ,erythrum ,martian date4 ,january #af ,on ,april #ai1 #aijc1 when1 after being hidden for thirty days1 owing to the different rotation periods of the two planets1 the ,mare ,erythraeum1 the largest blue-green region of the disk and lying in the southern hemisphere1 rounded again into view1 a startling transformation stood revealed in it4 ,instead of showing blue-green as usual1 and as it had done six weeks before1 it was now of a distinct chocolate-brown4 ,it had been well seen at its previous presentation1 so that no doubt existed of its then tint4 ,at that time the ,martian season corresponded to ,december #cj in our calendar4 ,eighteen ,martian days had since elapsed1 and it was now ,january #af there4 ,the metamorphosis had taken place1 therefore1 shortly after the winter solstice of that part of the planet4 ,the color change that had supervened proved permanent4 ,for the next night the region showed the same brown hue1 and so it continued to appear throughout the days that it was visible4 ,two months passed1 and then the chocolate hue had vanished1--gone as it had come1--and the mare had resumed its usual tint1 except for being somewhat pale at the south4 ,it had come to be ,february #ba on ,mars4 ,timed and tabulated1 the metamorphosis through which the mare passed stands out thus3-- ,,mare ,,erythraeum #aijc ,,days ,,before ,,or ,,after ,,summer ,,mundane ,,solstice ,,martian ,,date 7,,before - ,,date ,,aspect ,,after 7 ---------------------------------------- ------------------- ,february #af -#aj ,december #af ,blue-green ,march #bj #bb ,january #a ,blue-green ,april #ai #eb ,january #af ,chocolate ,april #bb #ee ,january #ah ,chocolate ,may #bf #hi ,february #d ,faint chocolate ,may #cj #ic ,february #f ,faint chocolate ,june #cj #abc ,february #bb ,faint blue-green ,july #g #acj ,february #be ,faint blue-green ,the culmination of the transformation seems to have taken place about #fj days after the southern winter solstice1 or in the depth of the ,martian winter of that hemisphere4 ,this is certainly just the time at which vegetation should be at its deadest4 ,the northern and southern portions of the mare did not behave alike in taking on the chocolate tint4 ,from the notes made about them during the opposition it appears that the latter was later than the former in undergoing the metamorphosis1 as will be seen from the following depth of the blue green estimated in percentages shown at different dates1 calling the deepest tone ever exhibited by it unity4 ,,martian ,,december ,,january ,,january ,,february ,,february ,,date1 7#af7 7#a7 7#ag7 7#e7 7#bd7 ---------------------------------------- ----------------- ,northern #ej #ej #j #be #ej ,southern #ej #ej #j #j #be ,from this table we may place the lowest point of the blue-green tint as reached about the #bb;d of ,january for the northern1 the #eth of ,february for the southern1 part4 ,this would indicate that the wave of returning growth came from the north1 not the south2 an important fact1 as we shall see later in studying the action of the canals4 ,illustration3 ,mare ,erythrum ,martian date4 ,february #a ,at the next opposition1 in #aije1 a recurrence of the transformation was watched for1 and not in vain4 ,it occurred1 however1 somewhat later in the ,martian season4 ,on ,december #bg of the planet's current year the ,mare ,erythraeum was still as usual1 blue-green1 nothing out of the ordinary being remarked in it2 and so it was on its ,january #ag1 although the southern edge was darker than the northern4 ,it looked certainly as if the metamorphosis were this year to be omitted4 ,but such was not the case4 ,when the region again came round1 on ,february #a of the ,martian calendar1 there the strange tint was as unmistakable as it had been on its original occurrence4 ,not only was the ,mare ,erythraeum so colored1 but on ,february #e 7,martian7 the northern portion of the ,mare ,cimmerium was observed to be similarly affected4 ,in the ,mare ,erythraeum the anomalous chocolate hue was confined to a belt between the latitudes of #aj and #bj south of the equator2 in the ,mare ,cimmerium it stretched a little higher1 from #aj at the west to #be at the east4 ,it is noteworthy that the southern portion of the latter showed blue at the time the northern showed brown4 ,then the metamorphosis proceeded as shown in the following table3-- ,,mare ,,erythraeum #aije ,,days ,,after ,,winter ,,mundane ,,solstice ,,of ,,southern ,,martian ,,aspect ,,date ,,hemisphere ,,date ---------------------------------------- ----------------------- ,january #be #ab ,december #bg ,blue-green ,march #f #eb ,january #af ,blue-green ,april #d #ha ,january #ca ,chocolate ,april #ab #hi ,february #d ,chocolate ,april #cj #ajg ,february #ac ,faint chocolate ,may #h #aae ,february #ag ,faint chocolate ,may #ab #aai ,february #ai ,faint blue-green ,june #aa #adi ,march #f ,faint blue-green ,june #ae #aec ,march #h ,faint blue-green ,july #af #ahd ,march #bc ,pale bluish green ,here1 as in #aijc1 a chromatic rise and fall is evident2 the culmination of the change occurring in ,martian early ,february about ninety days after the winter solstice4 ,that it was not of long duration is also indicated4 ,if we examine the evidence for the two portions of the mare separately1 the northern and the southern1 as in #aijc1 we find it as follows3-- ,,martian ,,december ,,january ,,february ,,february ,,march ,,march ,,date1 7#bg7 7#af7 7#b7 7#af7 7#g7 7#bc7 ---------------------------------------- ----------------------- ,northern #ej #ej #j #aj #be #cj ,southern #ej #ej #bj #bj #be #cj ,here again a slight retardation in the advent of the metamorphosis is observable in the southern portion4 ,there would seem to be a difference in the time of the change between the two years of fifteen days1 #aije being by that much the later4 ,but with points of reference themselves thirty days apart1 it is possible the two more nearly coincided than here appears4 ,unlike the ochre of the light regions generally1 which suggest desert pure and simple1 the chocolate-brown precisely mimicked the complexion of fallow ground4 ,when we consider the vegetal-like blue-green that it replaced1 and remember further the time of year at which it occurred upon both these ,martian years1 we can hardly resist the conclusion that it was something very like fallow field that was there uncovered to our view4 ,illustration3 ,mare ,erythrum ,martian date4 ,february #ba ,from the recurrence of the phenomenon on two successive years1 it is likely that it annually takes place4 ,that it is seasonal can scarcely be doubted from the timeliness of its occurrence1 and that different portions of its terrane successively underwent their metamorphosis shows further that it followed a law peculiar to the planet1 to which we shall be introduced when we come to consider the phenomena of the canals4 ,instances of relative hue in different dark patches corroboratory of seasonal variation1 and therefore of vegetal constitution1 might easily be adduced4 ,thus1 in #aije during the summer of the northern hemisphere1 the ,mare ,acidalium was notably darker than the ,mare ,erythraeum to the north of it1 which is what the law of seasonal variation would require1 since it was ,june in the one1 ,december in the other at the time4 ,but we need not to add example to example or proof to proof1 for there are no phenomena that contradict it4 ,we conclude1 therefore1 that the blue-green areas of ,mars are not seas1 but areas of vegetation4 ,just as reasoning to a negative result drifts us to the first conclusion1 so reasoning to a positive one lands us at the second4 ,,chapter ,,xii ,,terraqueousness ,,and ,,terrestriality ,with the vanishing of its seas we get for the first time solid ground on which to build our ,martian physiography4 ,the change in venue from oceans to land has produced a complete alteration in our judgment of the present state of the planet4 ,it destroys the analogy which was supposed to exist between ,mars and our earth1 and by abolishing the actuality of oceans there1 seems1 metaphorically1 to put us at first all the more at sea in our attempt to understand the planet4 ,but looked at more carefully1 it turns out to explain much that was obscure1 and in so doing gives us at once a wider view of the history of planetary evolution4 ,the trait concerned is cosmic4 ,study of the several planets of our solar system1 notably the ,earth1 ,moon1 and ,mars1 reveals tolerably legibly an interesting phase of a planet's career1 which apparently must happen to all such bodies1 and evidently has happened or is happening to these three3 the transition of its surface from a terraqueous to a purely terrestrial condition4 ,the terraqueous state is well exhibited by our own earth at the moment1 where lands and oceans share the surface between them4 ,the terrestrial is exemplified by both the ,moon and ,mars1 on whose surfaces no bodies of water at present exist4 ,that the one state passes by process of development into the other ,i shall now give my reasons for believing4 ,in the first place the appearance of the dark markings both on the ,moon and ,mars hints that though seas no longer1 they were seas once upon a time4 ,on the moon1 not only does their shape suggest this previous condition1 but the smooth and even look of their surfaces adds to the cogency of the inference4 ,more important1 however1 than either of these characteristics1 and confirmatory of both1 is the fact that the great tracts in question seem to lie below the level of the corrugated surface1 which is thickly strewn with volcanic cones4 ,their level and their levelness fay in explanation into one another4 ,the first makes possible the former presence of water2 the second speaks of its effect4 ,for their flat character hints that these areas were held down at the time when the other parts of the surface were being violently thrown up4 ,that they can themselves be cooled lava flows1 their extent and position seem enough to negative2 to say nothing of the fact that they should in that case lie above1 not below1 the general level4 ,something1 therefore1 covered them during the moon's eruptive youth and disappeared later4 ,such superincumbence may well have been water1 under which the now great plains lay then as ocean bottoms4 ,deep-sea soundings in our own oceans betray an ocean floor of the same extensive sort1 diversified as on the moon4 ,to call the lunar maria seas may not be so complete a misnomer after all2 but only a resurrecting in epitaph what was the truth in its day4 ,only doubtfully offered here for the ,moon1 for ,mars the inference seems more sure4 ,here again the dark regions not only look as they should had they had an earlier history1 but they1 too1 seem to lie below the level of the surface round about4 ,when they pass over the terminator they invariably show as flattenings upon it1 as if a slice of the surface had been pared off4 ,such profile in such pass is what ground at a lower level would present4 ,undoubtedly a part of the seeming depression is due to relative absence of irradiation consequent upon a more sombre tint1 but loss of light hardly seems capable of the whole effect4 ,in the case of ,mars1 then1 as with the ,moon1 a mistaken inference builded better than it knew1 if1 indeed1 we should rightly consider an inference to be mistaken which on half data lands us at the right door4 ,from the aspects of the dark regions we are led1 then1 to regard ,mars as having passed through that stage of existence in which the earth finds itself at the moment1 the stage at which oceans and seas form a feature of its landscape and an impediment to subjugation of its surface in its entirety4 ,what once were ocean beds have become ocean bottoms devoid of that which originally filled them4 ,that the process of parting with a watery envelop is an inevitable concomitant of the evolution of a planet from chaos to world1 we do not have to go so far afield as ,mars and the ,moon for testimony4 ,scrutiny reveals as much in the history of our own globe4 ,two signposts of the past1 one geologic1 the other paleontologic1 point unmistakably in this direction4 ,the geologic guides us the more directly to the goal4 ,study of the earth's surface reveals the preponderating encroachment of the land upon the sea since both began to be1 and demonstrates that1 except for local losses1 the oceans have been contracting in size from archaic times4 ,so much is evidenced by the successive places upon which marine beds have been laid down4 ,this suggests itself at once as a theoretic probability to one considering the matter from a cosmic standpoint1 and it is therefore the more interesting and conclusive that1 from an entirely different departure-point1 it should have been one of the pet propositions of the late ,professor ,dana1 who worked out conclusively the problem for ,north ,america1 and published charts detailing the progressive making of that continent4 ,illustration3 ,map of ,north ,america at the close of ,archan time1 showing approximately the areas of dry land4 7,from ,dana's 8,manual of ,geology407 ,so telling is this reclaiming by nature of land from the sea that it will be well to follow ,dana a little into detail1 as the details show effectively the continuity of the process acting through ons of geologic time4 ,at the beginning of the ,archan age1 or1 in other words1 at the epoch when stratified beds were first laid down1 the earth reached a turning-point in its history4 ,erosion1 superficial and sub-arial1 then set in to help restrict the domain of the sea4 ,at this juncture ,north ,america consisted of a sickle of terrane inclosing ,hudson's ,bay and coming down at its apex to a point not much removed from where ,ottawa now stands1 in about latitude #de--;a ,labradorian ,north ,america only4 ,this1 the kernel of the future continent1 curiously symbolized the form that continent was later to take4 ,for its eastern edge was roughly parallel to the present ,atlantic coastline1 although much within and to the north of it1 while its western one was similarly aligned afar off to the now ,pacific slope4 ,besides this continent proper1 the ,appalachian1 ,rocky ,mountain1 ,sierra ,nevada1 and ,sierra ,madre chains stood out of the ocean in long1 narrow ridges of detached land1 outlining in skeleton the bones of the continent that was to be4 ,the ,black ,hills of ,dakota and other highlands made here and there islets in the sea4 ,much the same backbone-showing of continents yet to be filled out was true of ,europe1 ,asia1 and ,south ,america4 ,in ,europe the northern countries constituted all that could be called continental land4 ,most of ,norway1 ,sweden1 ,finland1 ,lapland1 existed then1 while the northern half of ,scotland1 the outer ,hebrides1 portions of ,ireland1 ,england1 ,france1 and ,germany stood out as detached islands4 ,from this1 which is a fair sample of the proportion of land then to land now over the other continents so far as they are geologically known1 we turn to consider more in detail the history of ,north ,america4 ,by the time the ,upper ,silurian period came in1 the ,appalachian highlands there had been greatly extended and joined to the ,labradorian mainland by continuous territory2 otherwise1 no important addition had occurred1 though islands emerged in ,ohio1 ,kentucky1 and ,missouri4 ,illustration3 ,north ,america at the opening of the ,upper ,silurian4 7,from ,dana's 8,manual of ,geology407 ,at the commencement of the ,carbonic era what are now the ,middle states had begun to fill up from the north1 and ,newfoundland1 from a small island in the ,upper ,silurian1 had become a great promontory of ,labrador1 while the ,eastern states region and ,nova ,scotia had risen into being4 ,the movements closing ,paleozoic time upheaved from low islands the ,appalachian chain4 ,the earth's crust here crumpled by contraction upon itself2 and the movement ended1 as ,dana says1 by making dry land of the whole eastern half of the continent1 along substantially its present lines4 ,illustration3 ,map of ,north ,america after the ,appalachian ,revolution4 7,from ,dana's 8,manual of ,geology407 ,mesozoic time was the period of the making of the ,west4 ,it was an era of deposition and coincident subsidence1 when the western land had its nose just above water at one moment to be submerged the next4 ,though on the whole this part of the continent was emerging1 the fact was that1 synchronously with the sinking of the sea1 much of the land from time to time sank too4 ,the contraction which raised the ,appalachian ,mountains at the beginning of the period and that of the ,rockies at its close overdid the necessities of the case and caused subsidence elsewhere4 ,the southeastern portion of the continent suffered most1 the ,west on the whole materially gaining4 ,in the ,triassic and ,jurassic eras the gain was pronounced2 it occurred in the ,cretaceous also1 but with much alternation of loss4 ,finally1 at the close of the ,cretaceous1 the continent1 except for a prolonged ,gulf of ,mexico and vast internal lakes1 was substantially complete4 ,illustration3 ,north ,america in the ,cretaceous period4 7,from ,dana's 8,manual of ,geology407 ,the filling up of these lakes and the reclaiming of land from the ,gulf of ,mexico constituted the land-making work of ,tertiary times4 ,the extent of the lakes in the ,eocene era is held to show that the general level of the mountain plateau was low and rose later4 ,so that the gain by the land at this time was greater than the map allows to appear4 ,by the beginning of the ,quaternary epoch the continents had assumed their present general area1 and since then their internal features have alone suffered change4 ,illustration3 ,map of ,north ,america1 showing the parts under water in the ,tertiary ,era2 the vertically lined is the ,eocene4 7,from ,dana's 8,manual of ,geology407 ,a similar rising from the sea fell to the lot of ,europe1 though it has not been detailed with so much care4 ,the skeleton of that continent was at the beginning of depositary time much what it is to-day1 but a great inland sea occupied the centre of it1 which1 as time went on1 was gradually silted in and evaporated away1 notably during the ,upper ,silurian period4 ,from all this it is pretty clear that1 side by side with alternating risings and sinkings of the land1 there was a tolerably steady gain in the contest by which dry ground dispossessed the sea4 ,we may1 of course1 credit this to a general deepening of the ocean bottoms due to crumpling of the crust1 but we may also impute it to a loss of water1 and that the latter is1 at least for a part1 in the explanation the condition of the ,moon and ,mars makes probable4 ,paleontology has the same story of reclamation to tell as geology1 and with as much certainty1 though its evidence is circumstantial instead of direct and speaks for the growing importance of the land in the globe's economy since the beginning of depositary time1 and thus inferentially to its increasing extent4 ,fossil remains of the plants and creatures that have one after the other inhabited the earth show that the land has been steadily rising both in floral and faunal estimation as a habitat from the earliest ages to the present day4 ,the record lies imprinted in the strata consecutively laid down1 and except for gaps reads as directly on in bettering domicile as in evolutionary development4 ,in ,archan times we find no undisputed evidence of life either vegetal or animal4 ,but beds of graphite and of limestone point to the possible existence of both4 ,even anthracite has been found in ,archan rocks in ,norway and also in ,rhode ,island4 ,whether ,dawson's ,eozoon ,canadense be a rhizopod or a crystal1 doctors of science disagree4 ,dana1 while admitting nothing specific1 deems it antecedently probable that alg and later microscopic fungi related to bacteria existed then1 living in water well up toward the boiling-point4 ,indeed1 it is practically certain that invertebrate life existed1 because of its already well-developed character in the next era4 ,the like antedating is inferable for the whole record of the rocks4 ,relatively their history is undoubtedly fairly accurate1 but absolutely it must be shifted bodily backward into the next preceding era to correspond with fact not yet unearthed4 ,in the ,lower ,cambrian1 when first the existence of life becomes a certainty1 that life1 so far as known1 was wholly invertebrate and wholly marine2 rhizopods 7probably71 sponges and corals1 echinoderms1 worms1 brachiopods1 mollusks1 and crustaceans grew amid primitive seaweed and have left their houses in the shape of shells while perishing themselves4 ,their tracks too have thus survived4 ,the trilobites1 crustaceans somewhat resembling our horseshoe crab1 were the lords of the ,cambrian seas and marked the point to which organic evolution had then attained4 ,their aquatic character as well as their simple type is shown by their thoracic legs having each a natatory appendage4 ,in the next era1 the ,lower ,silurian1 the fauna and flora were still marine1 although of a higher order than before1 and in the ,trenton period1 the upper part of the era1 the earliest vertebrates1 fishes1 come upon the scene3 ganoids and possibly sharks4 ,nothing terrestrial of this period has yet with certainty been unearthed in ,america4 ,europe would seem to have either been more advanced then or better studied since1 for there the first plant higher than a seaweed has been dug up1 one of a fresh-water genus betokening the land2 while in keeping with this the first insect1 an hemipter1 also has been disinterred4 ,both the geography and the life of the ,eopaleozoic period ,dana styles 8thalassic40 ,neopaleozoic time1 beginning with the ,upper ,silurian1 marked the emergence of the continents1 and following them the emergence of life from the water on to this land4 ,in the lower beds of the ,upper ,silurian in ,america we find only the aquatic forms of previous strata1 but in a higher one we come in marshes upon plants related to the equiseta or horsetails4 ,in ,england land plants appear for the first time in these latest ,silurian beds and in the schists of ,angers have been preserved ferns4 ,in both the old world and the new fossil fishes are found and the oldest terrestrial species of scorpions4 ,but the great bulk of forms was still marine2 corals1 crinoids1 brachiopods1 trilobites constituting the principal inhabitants4 ,at this time the seas were warm1 having much the same temperature between #fe and #hj north as between #cj and #de2 the prevalence of a general temperate tropicality being shown by the fact that the common tropical chain corals lived in latitude #hb north4 ,in the ,devonian era1 the ,old ,red ,sandstone1 fishes grew and multiplied1 increasing in size apparently through the era1 and in the last period of it reaching their culminating point4 ,these pelagic vertebrates much surpassed in structure the terrestrial population of the time1 which was of a low type and consisted of invertebrates such as myriapods1 spiders1 scorpions1 and insects2 for the land was only making4 ,in the mid-,devonian1 forests of a primitive kind covered such country as there was1 an amphibious land1 composed of jungles and widespread marshes4 ,tree ferns made the bulk of the vegetation1 but among them grew also cycads and yews4 ,mammoth may-flies flitted through the gloom of these old forests1 but no vertebrate as yet had left the sea4 ,following upon the ,old ,red ,sandstone were laid down the ,carbonic strata1 and with the ,carbonic entered upon the scene the advance scouts of an army of progress evolutionarily impelled to spy out the land--the first amphibians4 ,they made their dbut in the ,subcarboniferous section of the era1 the oldest of the three periods into which the ,carbonic is divided1 crawling out of the sea to return again and leaving but footprints at first on the sands of time4 ,in the second period1 the ,coal-measures proper1 they ventured so far as to leave their skeletons on terra firma1 or rather infirma1 while their tracks there show them to have been now in great numbers4 ,in this manner the ancestors of the oldest land inhabitants began to struggle out of the sea4 ,in the ,permian1 the third and latest period of paleozoic times1 we find their descendants established in their new habitat1 for in it we come upon the first reptiles4 ,such possession marks a distinct step up in function as in fact1 for while amphibians visited dry land1 reptiles made it their home4 ,the getting out of the water had now1 in the case of the more evolved forms1 become an accomplished fact4 ,the reptiles were1 indeed1 the lowest and most generalized of their class1 ,rhynchocephalians1 8beak-headed0 species that by their teeth proclaim their marine origin and their relationship to the great amphibians that still felt undecided where to stay4 ,meanwhile1 in ,europe dragon-flies1 two feet across1 possessed the air2 while amphibians there1 as here1 ancestrally preceded reptiles in occupying the land4 ,mesozoic times were1 par excellence1 the age of monsters2 for the ,triassic 7the ,new ,red ,sandstone71 ,jurassic and ,cretaceous eras marked the reign of the reptiles4 ,great dinosaurs sleep still in the ,triassic strata of the ,atlantic border and in the ,jurassic of the ,western states1 to be unearthed from time to time and be given mausolea in our museums4 ,gigantic they were and very literally possessed the earth4 ,in ,europe they were substantially as in ,america during these mesozoic eras1 and showed their dominance by long survival in time as well as world-wide distribution in space2 for they lived all the way from ,kansas to ,new ,zealand and from the ,trias to the ,upper ,cretaceous4 ,it is supposed by ,professor ,osborn that many of them1 like the herbivorous brontosaurus1 waded in marshes1 not wholly unlike in habit to the modern hippopotamus4 ,others were land-stalking carnivores1 like the megalosaurs of a little later date4 ,of enormous size1 the largest exceeded any animal which has ever lived1 the whales alone excepted2 the biggest1 the atlantosaurus and the brontosaurus1 reaching a length of sixty feet4 ,for all their bulk they had scant brains1 just enough to enable them to feed and wallow1 probably4 ,it is interesting to note that many of the reptiles1 the less adventurous1 apparently reverted to the sea4 ,for though the crocodilians existed already in the ,trias1 the plesiosaurians did not come in till the ,middle ,trias in ,europe1 and the sea-serpents 7mosasaurus7 till the ,upper ,cretaceous4 ,though the dinosaurs dominated life in those days1 higher forms1 their descendants1 unnoticed were gradually creeping in1 eventually to supplant them4 ,for brain was making its way unobtrusively in the earliest of the mammals1 diminutive creatures at first and of the lowest type4 ,first appearing in the ,trias as something approaching the missing link between reptiles and mammals1 they later developed into monotremes and marsupials1 not rising in differentiation above the latter order to the end of ,mesozoic times4 ,and this both in the old world and the new4 ,in the ,jurassic1 too1 flying lizards and the first birds appeared1 showing their pedigree in their teeth4 ,with ,cenozoic times we come upon the first true or placental mammals with their culmination up to date in man4 ,in the ,eocene they were of a primitive type2 they were also of a comprehensive one1 fitted to eat anything4 ,from this they specialized1 some evolving and some on the whole devolving2 the whale1 for instance1 taking to the water in the ,eocene through the same degenerate proclivity that had characterized the sea-saurians ages before4 ,the earth was growing colder1 though still fairly warm1 and with the fall in temperature the higher types of life antithetically rose1 evolution gradually fitting them to cope with more advanced conditions4 ,in this manner did the land supplant the sea as the essential feature of the earth's surface1 first1 in coming into being1 and then1 by offering conditions fraught with greater possibilities1 as the habitat of the most advanced forms of life1 both plants and animals4 ,the possibility of advance in evolution was largely due to the fact that the land did thus supplant the sea4 ,spontaneous variation1 the as yet unexplained primum mobile in the genesis of species1 is probably to be referred to chemism and is likely later to receive its solution at the hands of that science4 ,in the meanwhile it is evident that unless the variation obtain encouragement from the environment no advance in type occurs4 ,now the land offers to an organism sufficiently evolved to benefit by it1 opportunities the sea does not possess4 ,first of these1 undoubtedly1 is the care it enables to be given to the young4 ,to cast one's brood upon the waters is not the best method of insuring its bringing up4 ,there is too much of the uncertainties of wave and current to make the process a healthy one1 and even when attached to rocks and seaweed1 the attachment to a mother is to be preferred4 ,without a period of infancy1 when the young is unable to do for itself1 no great development is possible4 ,in the only striking exception1 the case of the whales1 dolphins1 and porpoises1 size has probably counted for much in the matter1 while the development of the cetaceans is far behind that of the majority of land mammals4 ,change of place1 not in distance1 but in variety1 is another factor4 ,the sea is same as a habitat1 one square mile of it being much like another1 except for gradually changing temperature4 ,the land1 on the other hand1 from its accidented surface1 presents all manner of diversity in the conditions4 ,and the more varied the conditions to which the organism is exposed1 the greater its own complexity must be to enable it to meet them4 ,that the terrestrial stage of planetary development is subsequent to the terraqueous one1 and must of necessity succeed it if the latter ever exist on a body1 follows from the loss of internal heat on the one hand and from the kinetic theory of gases on the other4 ,to which of the two to attribute the lion's share in the business is matter for doubt2 but that both must be concerned in it we may take for certain4 ,so long as the internal heat suffices to keep the body fluid1 the liquid itself sees to it that all interstices are filled4 ,as the heat dissipates1 the body begins to solidify1 starting with the crust4 ,for cosmic purposes it undoubtedly still remains plastic1 but cracks of relatively small size are both formed and persist4 ,into these the surface water seeps4 ,with continued refrigeration the crust thickens1 more cracks are opened and more water given lodgment within1 to the impoverishment of the seas4 ,the process would continue till the pressure of the crust itself rendered plastic all that lay below1 beyond which1 of course1 no fissures could be formed4 ,how competent to swallow all the seas such earth cuticle cracks may be we ignore2 for we cannot be said to know much of the process4 ,we can only infer that to a certain extent internal absorption of surface seas must mark a stage of the evolution by which a star becomes a world and then an inert mass1 one of the dark bodies of which space is full4 ,of the other means we know more4 ,we are certain that it must take place1 though we are in doubt as to the amount it has already accomplished4 ,this method of depletion is by the departure of the water in the form of gas1 in consequence of the molecular motions4 ,if we knew the temperature and the age of ,mars and also the amount of atmosphere originally surrounding it1 we could possibly predicate its state4 ,reversely1 we can infer something as to age and temperature from its present condition4 ,,chapter ,,xiii ,,the ,,reddish-,,ochre ,,tracts ,both for their evidence and their extent the great ochre stretches of the disk claim attention first4 ,largely unchangeable1 these show essentially the same day after day and from the year's beginning to its end4 ,in hue they range from sand color to a brick red2 some parts of the planet being given to the one tint1 some to the other4 ,it is to the latter that the fiery tint of ,mars to the naked eye is due4 ,the differences in complexion are local and peculiar1 both in place and time4 ,for though saffron best paints the greater part of the light areas1 certain localities present at times a red like that of our red sandstone4 ,hellas is one of these ruddy regions and ,aeria another4 ,it is only on occasion that they thus show1 and to what to assign their variability is as yet matter of conjecture4 ,possibly it is owing to ,martian meteorologic condition2 possibly to something else4 ,but whatever its origin1 the change is not so much contradictory of1 as supplementary to1 the general fact of unalterableness1 which is after all the basic trait about them and the keynote to their condition4 ,land the ochre regions have generally been taken for1 and land they still make good their claim to be considered4 ,for the better they are seen1 the greater the ground for the belief4 ,indeed1 they seem to be nothing but ground1 or1 in other words1 deserts4 ,their color first points them out for such4 ,the pale salmon hue1 which best reproduces in drawings the general tint of their surface1 is that which our own deserts wear4 ,the ,sahara has this look2 still more it finds its counterpart in the far aspect of the ,painted ,desert of northern ,arizona4 ,to one standing on the summit of the ,san ,francisco ,peaks and gazing off from that isolated height upon this other isolation of aridity1 the resemblance of its lambent saffron to the telescopic tints of the ,martian globe is strikingly impressive4 ,far forest and still farther desert are transmuted by distance into mere washes of color1 the one robin's-egg blue1 the other roseate ochre1 and so bathed1 both1 in the flood of sunshine from out a cloudless burnished sky that their tints rival those of a fire-opal4 ,none otherwise do the ,martian colors stand out upon the disk at the far end of the journey down the telescope's tube4 ,even in its mottlings the one expanse recalls the other4 ,to the ,painted ,desert its predominating tint is given by the new red sandstone of the ,trias1 the stratum here exposed2 and this shows in all its pristine nakedness because of the lack of water to clothe it with any but the sparsest growth4 ,limestones that crop out beside it are lighter yellow1 whitish and steel-gray1 and seen near give the terrane the look of a painter's palette4 ,seen from far they have rather the tint of sand2 and the one effect1 like the other1 is ,martian in look4 ,and as if to assimilate the two planetary appearances the more1 the thread of blue-green that attention traces athwart the ,painted ,desert marks the line of cottonwoods along the banks of the ,little ,colorado ,river--deserts both1 if look be any guarantee of character1 with verdure banding them4 ,in other ways these earthly deserts offer a parallel to the ,martian4 ,no desert on the ,earth is absolutely devoid of life of some kind1 vegetal and animal4 ,the worst conditioned are not what one is taught in childhood to believe a desert to be--a vast waste of sand1 with a camel and a palm thrown in to heighten the sterility4 ,in all ,saharas outside of the pages of the school books some vegetation grows1 though it is commonly not of a kind to boast of1 being rather a succs d'estime1 as sagebrush1 cacti1 and the like4 ,but what is of interest here in the connection is its color4 ,for it is commonly of a more ochreish tint than usual1 in keeping with its surroundings1 a paling out of the green to something more tawny1 indicating a relative reduction of the chlorophyll and an increase of the lipochromes in the tissues of the plant1 since the one gives the green tint to the leaves1 the other the yellow4 ,as this vegetation1 poor as it is1 has its annual history1 it must alter the look of the desert at times and produce precisely those slight variations in tint observable on ,mars in like circumstance4 ,the ,arizona desert dates from no further back than early ,tertiary times1 as the limestone of the ,cretaceous there present shows4 ,water then stretched where desert now is1 and the limestone beds were laid down in it4 ,how old the ,martian ,saharas are we have no means of knowing4 ,but one thing we may predicate about both3 a desert is not an original1 but an acquired1 condition of a planet's surface1 demonstrably so in the case of a planet which has had a sedimentary epoch in its life-history4 ,in the ,arizona desert the surface is composed of depositary rocks of ,mesozoic times1 except where lava streams have flowed down over it since then4 ,the land1 then1 was once under water1 and cannot but have been fertile for some time after it emerged4 ,but we are not left to inference in the matter1 however good that inference may be4 ,a little to the south of the ,painted ,desert1 in the midst of the barren plateau of northern ,arizona1 of which the former makes a part1 stand the remains of a petrified forest4 ,huge chalcedony trunks of trees1 so savingly transmuted into stone that their genus is still decipherable1 lie scattered here over the barren ground in waste profusion1 one of them still spanning a caon just as it fell in that1 to it1 destructive day of a far prehistoric past4 ,the rock stratum on which their remains lie is of ,triassic and ,cretaceous times and the petrifications show that in the ,cretaceous a stately forest overspread the land4 ,in those days at least the spot was fertile where now sparse sagebrush and cacti find a living hard4 ,not here alone where the blocks are so conspicuous as to invite their carrying away is a former flourishing growth of vegetation attested1 but over large adjoining areas of desert search has brought the like past tenancy to light4 ,fragments of what once were trees have been picked up in the ,little ,colorado basin and in the neighborhood of ,ash ,fork1 on both sides1 that is1 of the present forest crown that covers the higher part of the plateau from which rise the ,san ,francisco ,peaks4 ,in the blue distance the mountains look down verdure-clad upon a now encircling waste1 but one which in earlier eras was as pine-bearing as they4 ,their lofty oasis is all that is now left of a once fertile country2 the retreat of the trees up the slopes in consequence of a diminishing rainfall1 until a rise of two thousand feet from what once was timber-land is necessary to reach the tree-line of today1 being typical of desert lands1 and testifying to greater aqueous affluence in the past4 ,in the same manner streams descend from the cedar-clad range of the ,lebanon to lose themselves in the ,arabian desert just without the doors of ,damascus2 and ,palestine has desiccated within history times4 ,palestine1 a land once flowing with milk and honey1 can hardly flow poor water now1 and furnishes another straw to mark the ebbing of the water supply4 ,this making of deserts is not a sporadic1 accidental1 or local matter1 although local causes have abetted or hindered it4 ,on the contrary1 it is an inevitable result of planetary evolution1 a phase of that evolution which follows from what has been said in ,chapter ,,xii on the abandonment of a planet by its water4 ,deserts are simply another sign of the same process4 ,the very aging which began by depriving a body of its seas takes from it later its forest and its grass4 ,a growing scarcity of water is bound to depauperate the one1 as it depletes the other4 ,we have positive proof of the action in our own deserts4 ,for these bear testimony1 in places at least1 to not having always been so1 but to have gradually become so within relatively recent times4 ,but we have more general proof of the action from the position occupied on the earth's surface by its deserts4 ,the significant fact about the desert-making so stealthily going on is that only certain zones of the earth's surface are affected4 ,those belting the two tropics of ,cancer and ,capricorn1 for several degrees on either side of them1 most exhibit the phenomenon4 ,such positioning of the deserts is not due to chance4 ,directly1 of course1 desertism is due to dearth of rain4 ,this in turn depends on the character and condition of the winds4 ,if a wind laden with moisture travel into a colder region of the globe1 its moisture is precipitated in rain and we have a fertile country2 if it voyage into a warmer clime it takes up what little moisture may be there already and a desert is the result4 ,now our system of winds is such as to produce a fall of rain for the different latitudes1 as tabulated by ,supan1 thus3-- ,zone ,i #dj,n-#bg,n ,little rain in summer but much in winter4 ,,ii #bg ,n-#ai ,n ,little rain at all seasons4 ,,iii #ai ,n- #g ,n ,little rain in winter but much in summer4 ,,iv #g ,n- #a ,n ,abundant rain at all seasons4 ,v #a ,n-#ag ,s ,little rain in winter but much in summer4 ,,vi #ag ,s-#cj ,s ,little rain at all seasons4 ,,vii #cj ,s-#ce ,s ,little rain in summer but much in winter4 ,zones ,,ii and ,,vi1 the zones of minimum rainfall1 are also those in which the deserts occur4 ,the northern one traverses southern ,california1 ,arizona1 ,new ,mexico1 the ,sahara1 ,arabia1 and the ,desert of ,gobi2 the southern1 ,peru1 the ,south ,african veldt1 and central ,australia4 ,the belts are wavy bands which by their form betray both a general underlying trend to drought at these parallels and also the effect of local topography in the matter4 ,from being distributed thus in belts1 it is evident that the deserts are general globe phenomena1 and from their being found only in the zones of least rainfall1 that the earth has itself entered1 though not far as yet1 upon the desert stage of its history4 ,once begun1 the desert areas must perforce spread as water becomes scarce1 invading and occupying territory in proportion as the rainfall there grows small4 ,now the axial tilt of ,mars is almost exactly the same as that of our ,earth1 the latest determinations from the ensemble of measures giving #bd for it4 ,here1 then1 we have initial conditions reproducing those of the earth4 ,but from the smaller size of the planet that body would age the earlier1 since it would lose its internal heat the more rapidly1 just as a small stone cools sooner than a larger one4 ,on general principles1 therefore1 it should now be more advanced in its planetary career4 ,in consequence1 desertism should have overtaken more of its surface than has yet happened on earth1 and instead of narrow belts of sterility we should expect to find there ,saharas of relatively vast extent4 ,now1 such a state of things is precisely what the telescope reveals4 ,the ochre tracts occupy nine tenths of the northern hemisphere and a third of the southern4 ,three fifths1 therefore1 of the whole surface of the planet is a desert4 ,illustration3 ,desert areas4 ,of cosmic as well as of particular import is the correlation thus made evident between the physical principles that effect the aging of a planet and the aspect ,mars presents4 ,experimental corroboration of those laws is thus afforded1 while1 reversely1 confidence in their applicability is increased4 ,with continued observation the planet appears more desiccate as improved conditions bring it nearer4 ,dry land as it was thought to be proves even drier1 something which lacks water for the ordinary necessities of a living world4 ,illustration3 ,desert areas4 ,the picture the planet offers to us is thus arid beyond present analogue on ,earth4 ,pitiless as our deserts are1 they are but faint forecasts of the state of things existent on ,mars at the present time4 ,only those who as travelers have had experience of our own ,saharas can adequately picture what ,mars is like and what so waterless a condition means4 ,only such can understand what is implied in having the local and avoidable thus extended into the unescapable and the world-wide2 and what a terrible significance for everything ,martian lies in that single word3 desert4 ,,chapter ,,xiv ,,summary ,if1 now1 we review with the mind's eye the several features of ,mars which we have surveyed with the bodily one1 we shall be surprised to find to what they commit us4 ,suggestive as each is considered by itself1 the ensemble into which they combine proves of multiplicate force in its implication4 ,for each turns out to fit into place in one consistent whole1 a scheme of things in which are present all the conditions necessary to the existence and continuance of those processes which constitute what we call life4 ,in short1 we are conducted with a cogency1 which grows as we consider it1 to the conclusion that ,mars is habitable4 ,two ways of appreciating this cogency are open to us4 ,we may treat it with the simple reasoning of common-sense1 as we should a dissected map or a piece of machinery in which we realize we are right when the several parts at last fit together and the picture stands revealed or the machine works4 ,or we may subject the evidence to quantitative estimates for and against by the doctrine of probabilities1 and thus evaluate the chances of its being correct4 ,consciously or unconsciously1 this is what we are about in our decisions every day of our lives4 ,at the one end of the line are those skillful judgments where the balance is so keen-edged that the least overweight on the one side dips the scales to a conclusion4 ,at the other extremity stand those deductions which we usually speak of as proved1 such as the law of gravitation4 ,but both assurances rest really upon probability and differ only in degree4 ,what we mean by proof of anything is that a supposition advanced to account for it explains all the facts and is not opposed to any of them1 and that the balance of probability in consequence is very largely in its favor4 ,now1 if several pieces of evidence1 distinct in their origin1 concur to a given conclusion1 the probability that that conclusion is correct is far greater than what results from each alone2 and mounts up soon to something much exceeding what bettors at races call certainty odds4 ,however unversed the average man may be in calculating the probability1 he recognizes the fact in his dealings with his fellows by the way he attaches weight to concurrent testimony4 ,it is such concurrent evidence that we have now to consider4 ,to this end we will marshal the several facts ascertained in a summarized list for their easier intercomparison4 ,these facts are3-- 7#a7 ,mars turns on its axis in #bd h4 #cg m4 #bb4fe s4 with reference to the stars1 and in #bd h4 #ci m4 #ce4j s4 7as a mean7 with regard to the ,sun4 ,its day1 therefore1 is only about forty minutes longer than ours4 7#b7 ,its axis is tilted to the plane of its orbit by about #bc #ei 7most recent determination1 #aije74 ,this gives the planet seasons almost the counterpart of our own in character2 but in length nearly double ours1 for 7#c7 ,its year consists of #fhg of our days1 #ffi of its own4 7#d7 ,polar caps are plainly visible which melt in the ,martian summer to form again in the ,martian winter1 thus implying the presence of a substance deposited by cold4 7#e7 ,as the polar caps melt1 they are bordered by a blue belt1 which retreats with them4 ,this excludes the possibility of their being formed of carbon dioxide1 and shows that of all the substances we know the material composing them must be water4 7#f7 ,in the case of the southern cap1 the blue belt has widenings in it in places4 ,these occur where the blue-green areas bordering upon the polar cap are largest4 7#g7 ,the extensive shrinkage of the polar snows shows their quantity to be inconsiderable1 and points to scanty deposition due to dearth of water4 7#h7 ,the melting takes place locally after the same general order and method1 ,martian year after year1 both in the south cap1 7#i7 ,and in the north one4 ,this is evidenced by the recurrence of rifts in the same places annually in each4 ,the water thus let loose can1 therefore1 be locally counted on4 7#aj7 ,that the south polar cap is given to greater extremes than the north one1 implies again1 in view of the eccentricity of the orbit and the tilt of the axis1 that deposition in both caps is light4 7#aa7 ,the polar seas at the edges of the caps being temporary affairs1 the water from them must be fresh4 7#ab7 ,the melting of the caps on the one hand and their reforming on the other affirm the presence of water vapor in the ,martian atmosphere1 of whatever else that air consist4 7#ac7 ,since water vapor is present1 of which the molecular weight is #ah1 it follows from the kinetic theory of gases that nitrogen1 oxygen1 and carbonic acid1 of molecular weights #bh1 #cb1 and #ch respectively1 are probably there1 too1 owing to being heavier4 7#ad7 ,the limb-light bears testimony to this atmosphere4 7#ae7 ,the planet's low albedo points to a density for the atmosphere very much less than our own4 7#af7 ,the apparent evidence of a twilight goes to confirm this4 7#ag7 ,permanent markings show upon the disk1 proving that the surface itself is visible4 7#ah7 ,outside of the polar cap the disk is divided into red-ochre and blue-green regions4 ,the red-ochre stretches have the same appearance as our deserts seen from afar1 7#ai7 ,and behave as such1 being but little affected by change4 7#bj7 ,the blue-green areas were once thought to be seas4 ,but they cannot be such1 because they change in tint according to the ,martian season1 and the area and amount of the lightening is not offset at the time by corresponding darkening elsewhere2 7#ba7 ,nor by any augmentation of the other polar cap or precipitation into cloud4 ,it cannot1 therefore1 be due to shift of substance4 7#bb7 ,furthermore1 they are all seamed by lines and spots darker than themselves which are permanent in place2 so that there can be no bodies of water on the planet4 7#bc7 ,on the other hand1 their color1 blue-green1 is that of vegetation2 this regularly fades out1 as vegetation would1 to ochre for the most part1 but in places changes to a chocolate-brown4 7#bd7 ,the change that comes over them is seasonal in period1 as that of vegetation would be4 7#be7 ,each hemisphere undergoes this metamorphosis in turn4 7#bf7 ,that it is recurrent is again proof positive of an atmosphere4 7#bg7 ,the changes are metabolic1 since those in one direction are later reversed to a restoration of the original status4 ,anabolic as well as katabolic processes thus go on there2 that is1 growth as well as decay takes place4 ,this proves them of vegetal origin4 7#bh7 ,the existence of vegetation shows that carbonic acid1 oxygen1 and undoubtedly nitrogen1 are present in the ,martian atmosphere1 since plants give out oxygen and take in carbonic acid4 7#bi7 ,the changes in the dark areas follow upon the melting of the polar caps1 not occurring until after that melting is under way2 7#cj7 ,and not immediately then1 but only after the lapse of a certain time4 7#ca7 ,though not seas now1 from their look the dark areas suggest old sea bottoms1 and when on the terminator appear as depressions 7whether because really at a lower level or because of less illumination is not certain74 7#cb7 ,that they are now the parts of the planet to support vegetation hints the same past office1 as water would naturally drain into them4 ,that such a metamorphosis should occur with planetary aging is in keeping with the kinetic theory of gases4 7#cc7 ,terminator observations prove conclusively that there are no mountains on ,mars1 but that the surface is surprisingly flat4 7#cd7 ,but they do reveal clouds which are usually rare and are often1 if not always1 dust-storms4 7#ce7 ,white spots are occasionally visible1 lasting unchanged for weeks1 in the tropic and temperate regions1 showing that the climate is apparently cold1 7#cf7 ,but at the same time proving that most of the surface has a temperature above the freezing-point4 7#cg7 ,in winter the temperate zones are more or less covered by a whitish veil1 which may be hoar-frost or may be cloud4 7#ch7 ,a spring haze surrounds the north polar cap during the weeks that follow its most extensive melting4 7#ci7 ,otherwise the ,martian sky is perfectly clear2 like that of a dry and desert land4 ,the way in which these thirty-nine articles fit into one another to a mortised whole is striking enough at first sight1 but becomes more and more impressive the more one considers it4 ,for some are due to one kind of observation1 some to another4 ,in the taking they are unrelated2 yet in the result they agree4 ,equally pregnant is the history of their acquisition4 ,most of them were detected as the outcome of observations at the opposition of #ahid1 and led to the theory which was published in the writer's first book on the subject4 ,others are the result of the five oppositions that have since occurred4 ,these have proved entirely corroborative of the previous ones and of the theory then deduced1 and that in two distinct ways3 first1 by the accumulated evidence they have brought to the matter along the old lines2 and1 secondly1 by what they have revealed in new directions4 ,of these thirty-nine articles of ,martian scientific faith in observation or deduction1 7#i71 7#aj71 7#ba71 7#bb71 7#be71 7#bg71 7#bh71 7#cj71 7#cc71 7#ce71 7#cf71 and 7#ch7 are in whole or part new4 ,that continued scrutiny is thus corroborative of the earlier results1 both along the old and along new lines of investigation1 warrants additional confidence in the conclusion4 ,considering1 now1 these counts1 we see that they make reasonably evident on ,mars the presence of3-- #a4 ,days and seasons substantially like our own2 #b4 ,an atmosphere containing water vapor1 carbonic acid1 and oxygen2 #c4 ,water in great scarcity2 #d4 ,a temperature colder than ours1 but above the ,fahrenheit freezing-point1 except in winter and in the extreme polar regions2 #e4 ,vegetation4 ,first and foremost of these is air4 ,in order to make it possible for vital processes of any sort to take place1 the body of a planet must be clothed with an atmosphere1 by the modesty of nature1 the old astronomers would have said4 ,such a covering subserves two purposes3 it keeps out the cold of space1 thus permitting the maintenance of a temperature sufficient to support life1 and it affords a medium through which metabolism can go on4 ,now the presence of air is attested first and foremost by the fact of change in the ,martian markings1 7#ab71 7#ac71 7#bf71 7#bh71 and 7#ce74 ,the changes observed are conspicuous2 are both inorganic 7in the case of the polar caps71 7#ab71 7#ac71 and 7#ce71 and metabolic or organic1 7#bf7 and 7#bh71 7in the case of the blue-green areas72 that is1 they consist of building up as well as of pulling down and are planet-wide in occurrence4 ,such changes could not occur in the absence of an atmosphere4 ,they show that this atmosphere consists of water vapor1 7#e71 carbonic acid1 and oxygen1 7#bh74 ,the limb-light1 the apparent evidence of a twilight arc and the planet's low albedo indicate that this atmosphere is thin4 ,the appearance of the surface1 7#ce71 suggests cold1 indicative again of a thin air4 ,such tenuity is in accord with what a priori principles would lead us to expect1 and tends to show that reliance on general principles is here not misplaced1 a point of some interest4 ,lastly1 the occurrence of clouds1 7#cd71 visibly floating and traveling over the surface1 and haze at times1 7#ch71 proves in another way the existence of the medium in which alone this could be possible4 ,water is the next substance vital to planetary life4 ,as to its actual presence the polar caps1 7#d7-7ab71 have most to say2 as to its relative absence1 the rest of the disk1 7#ag7-7bb74 ,the forthright conception of the polar caps as composed of snow and ice is borne out by further investigation into what could cause the observed phenomenon4 ,carbonic acid1 the only other substance we know capable in any way of resembling what we see1 turns out not capable of producing one important detail of the caps' appearance1 the blue band1 7#e71 which accompanies them in their retreat4 ,water alone could do this4 ,the melting of the caps shows that water vapor must be a constituent of the ,martian atmosphere4 ,moreover1 as the molecular weight of water vapor is less than that of oxygen or nitrogen or carbon dioxide1 if the former can exist in the atmosphere of the planet1 a fortiori must these other gases4 ,so that from this we have knowledge of the possibility of the presence of oxygen1 nitrogen1 and carbon dioxide there4 ,from 7#bh7 we saw that their actual existence is demonstrated4 ,the next step is the ascertainment that the water is in very small amount4 ,the extensive melting of the caps1 7#g71 shows their quantity to be inconsiderable1 which is the first fact pointing to a dearth of water4 ,the second comes from the aspect and behavior of the reddish-ochre regions which proclaim them deserts1 7#ah7 and 7#ai72 the third from the detection of the character of the blue-green areas as not seas1 7#bj71 7#ba71 and 7#bb74 ,in several different ways1 study of these regions asserts their non-aquatic constitution1 the easiest to appreciate being that they are traversed by permanent dark lines and other equally sedentary markings1 7#bb74 ,no bodies of water1 therefore1 are to be seen outside of the ephemeral polar seas1 immediately surrounding the caps as they melt4 ,this leads us to the third presence on ,mars indicative of a living world3 vegetation4 ,the other two spoke of substances necessary to life1 the premises in the case1 this one of organic existence itself1 its conclusion4 ,the evidence consists of static testimony from the look of the blue-green areas1 7#bc71 and of kinematic derived from their behavior1 7#bd71 7#be71 7#bf71 and 7#bg74 ,vegetation would present exactly the appearance shown by them1 and nothing that we know of but vegetation could4 ,but suggestive as their appearance is1 it is as nothing compared with the cogent telltale character of their behavior4 ,the seasonal change that sweeps over them is metabolic1 constructive as well as destructive1 that is1 and proclaims an organic constitution for them such as only vegetation could produce4 ,in tint their metamorphoses are those of the same substance4 ,for the blue-green lapses into ochre and revives again to blue-green just as vegetation does on our own ,earth at the proper season of the year1 taking both the ,sun and the advent of water into the reckoning4 ,furthermore1 certain of the largest dark areas turn to a chocolate-brown at times1 which is the color of fallow ground and suggestive1 at least1 as occurring where the blue-green at other seasons is the most pronounced4 ,lastly1 the change occurs at the epoch at which1 from a knowledge of the melting of the polar caps1 theory demonstrates that it ought to take place if it be due to the action of vegetation4 ,that this was the case was evident from much less information than is forthcoming today2 but what is significant1 each new fact discovered about the planet goes to show that it is unquestionably true4 ,,part ,,ii ,,non-,,natural ,,features ,,chapter ,,xv ,,the ,,canals ,from the detection of the main markings that diversify the surface of ,mars we now pass to a discovery of so unprecedented a character that the scientific world was at first loath to accept it4 ,only persistent corroboration has finally broken down distrust2 and1 even so1 doubt of the genuineness of the phenomena still lingers in the minds of many who have not themselves seen the sight because of the inherent difficulty of the observations4 ,for it is not one where confirmation may be summoned in the laboratory at will1 but one demanding that the watcher should wait upon the sky1 with more than ordinary acumen4 ,this latter-day revelation is the discovery of the canals4 ,quite unlike in look to the main features of the planet's face is this second set of markings which traverse its disk1 and which the genius of ,schiaparelli disclosed4 ,unnatural they may well be deemed2 for they are not in the least what one would expect to see4 ,they differ from the first class1 not in degree1 but in kind2 and the kind is of a wholly unparalleled sort4 ,while the former bear a family resemblance to those of the earth2 the latter are peculiar to ,mars1 finding no counterpart upon the earth at all4 ,introduction to the mystery came about in this wise1 and will be repeated for him who is successful in his search4 ,when a fairly acute eyed observer sets himself to scan the telescopic disk of the planet in steady air1 he will1 after noting the dazzling contour of the white polar cap and the sharp outlines of the blue-green seas1 of a sudden be made aware of a vision as of a thread stretched somewhere from the blue-green across the orange areas of the disk4 ,gone as quickly as it came1 he will instinctively doubt his own eyesight1 and credit to illusion what can so unaccountably disappear4 ,gaze as hard as he will1 no power of his can recall it1 when1 with the same startling abruptness1 the thing stands before his eyes again4 ,convinced1 after three or four such showings1 that the vision is real1 he will still be left wondering what and where it was4 ,for so short and sudden are its apparitions that the locating of it is dubiously hard4 ,it is gone each time before he has got its bearings4 ,by persistent watch1 however1 for the best instants of definition1 backed by the knowledge of what he is to see1 he will find its coming more frequent1 more certain and more detailed4 ,at last some particularly propitious moment will disclose its relation to well-known points and its position be assured4 ,first one such thread and then another will make its presence evident2 and then he will note that each always appears in place4 ,repetition in situ will convince him that these strange visitants are as real as the main markings1 and are as permanent as they4 ,such is the experience every observer of them has had2 and success depends upon the acuteness of the observer's eye and upon the persistence with which he watches for the best moments in the steadiest air4 ,certain as persistence is to be rewarded at last1 the difficulty inherent in the observations is ordinarily great4 ,not everybody can see these delicate features at first sight1 even when pointed out to them2 and to perceive their more minute details takes a trained as well as an acute eye1 observing under the best conditions4 ,when so viewed1 however1 the disk of the planet takes on a most singular appearance4 ,it looks as if it had been cobwebbed all over4 ,suggestive of a spider's web seen against the grass of a spring morning1 a mesh of fine reticulated lines overspreads it1 which with attention proves to compass the globe from one pole to the other4 ,the chief difference between it and a spider's work is one of size1 supplemented by greater complexity1 but both are joys of geometric beauty4 ,for the lines are of individually uniform width1 of exceeding tenuity1 and of great length4 ,these are the ,martian canals4 ,two stages in the recognition of the reality confront the persevering plodder3 first1 the perception of the canals at all2 and1 second1 the realization of their very definite character4 ,it is wholly due to lack of suitable conditions that the true form of the ,martian lines is usually missed4 ,given the proper prerequisites of location or of eye1 and their pencil-mark peculiarity stands forth unmistakably confessed4 ,it is only where the seeing or the sight is at fault that the canals either fail to show or appear as diffuse streaks1 the latter being a halfway revelation between the reality and their not being revealed at all4 ,much misconception exists on this point4 ,it has been supposed that improved atmospheric conditions simply amount to bringing the object nearer by permitting greater magnification without altering the hazy look of its detail4#b ,not so4 ,they do much more than this4 ,they steady the object much as if a page of print from being violently shaken should suddenly be held still4 ,the observer would at once read what before had escaped him for being a blur4 ,so is it with the canals4 ,in reality1 pencilings of extreme tenuity1 the agitations of our own air spread them into diffuse streaks2 an effect of which any one may assure himself by sufficiently rapid motion of a drawing in which they are depicted sharp and distinct1 when he will see them take on the streaky look4 ,as the writer has observed them under both aspects1 and has seen them pass from the indefinite to the defined as the seeing improved1 he has had practical proof of the fact1 and this not once1 but an untold number of times4 ,atmospheric conditions far superior to what are good enough for most astronomic observations are needed for such planetary decipherment1 and the observer experienced in the subject eventually learns how all-important this is4 ,under these conditions the testimony of his own eyesight upon the character of these markings is definite and complete4 ,and the first trait that then emerges from confusion is that the markings are lines2 not simply lines in the sense that any sufficiently narrow and continuous marking may so be called1 but lines in the far more precise sense in which geometry uses the term4 ,they are furthermore straight lines4 ,as ,schiaparelli said of them3 they look to have been laid down by rule and compass4 ,the very marvel of the sight has been its own stumbling-block to recognition1 joined to the difficulty of its detection4 ,for not only is the average observatory not equipped by nature for the task1 but what is not good air often masquerades as such4 ,trains of air waves exist at times so fine as to confuse this detail1 or even to obliterate it entirely2 while at the same time they leave the disk seemingly sharp-cut1 with the result that one not well versed in such vagaries thinks to see well when in truth he is debarred from seeing at all4 ,when study of the conditions finally ends in putting him upon the right road1 the sight that rewards him can hardly be too graphically described4 ,next to the fact that they are lines1 definiteness of direction is the chief of their characteristics to strike the observer4 ,the lines run straight throughout their course4 ,this is absolutely true of ninety per cent of them1 and practically so of the remaining ten per cent1 since the latter curve in an equally symmetric manner4 ,such directness has ,i know not what of immediate impressiveness4 ,quite unlike the aspect of the main markings1 which show a natural irregularity of outline1 these lines offer at the first glance a most unnatural regularity of look4 ,nothing on ,earth of natural origin on such a scale bears them analogue4 ,nor does any other planet show the like4 ,they are1 in fact1 distinctively ,martian phenomena4 ,this is the first point in which they differ from the markings we have hitherto described4 ,the others were generic planetary features2 these are specific ones1 peculiar to ,mars4#c ,equally striking is the uniform width of each line from its beginning to its end1 as it stands out there upon the disk4 ,the line varies not in size throughout its course any more than it deviates in direction4 ,it counterfeits a telegraph wire stretched from point to point4 ,like the latter seen afar1 the width1 too1 is telegraphic4 ,for it is not so much width as want of it that is evident4 ,breadth is inferable solely from the fact that the line is seen at all1 and relative size by difference of insistency4 ,indeed1 the apparent breadth has been steadily contracting as the instrumental1 atmospheric1 and personal conditions have improved4 ,all three of the factors have conduced to such emaceration1 but the middle one the most4 ,for the air waves spread every marking1 and the effect is relatively greatest upon those which are most slender4 ,as the currents of condensation and rarefaction pulse along1 their denser and their thinner portions refract the rays on either side of their true place1 and thus at the same time confuse a marking and broaden it4 ,the consequence is that the better the atmospheric conditions and the more that has been learned about utilizing them1 the finer the lines have shown themselves to be4 ,herein we have a specific intrinsic difference between the fundamental features and these lines3 the main markings have extension in two dimensions1 the latter in one4 ,distinctive as they thus are1 they have1 in keeping with their appearance1 been given a distinctive name1 that of canal4 ,useful as the name is and1 as we shall later see1 applicable1 it must not be supposed that what we see are such in any simple sense4 ,no observer of them has ever considered them canals dug like the ,suez ,canal or the phnix-like ,panama one4 ,this supposition is exclusively of critic creation4 ,their precise width is not precisable4 ,they show no measurable breadth and their size1 therefore1 admits for certain only of an outside limit4 ,they cannot be wider than a determinable maximum1 but they may be much less than this4 ,the sole method of estimating their width is by comparison of effect with a wire of known caliber at a known distance4 ,for this purpose a telegraph wire was stretched against the sky at ,flagstaff1 and the observers1 going back upon the mesa1 observed and recorded its appearance as their stations grew remote4 ,it proved surprising at what great distances a slender wire could be made out when thus projected against the sky4 ,the wire in the experiment was but #j4jgbf of an inch in diameter and yet could be seen with certainty at a distance of #ahjj feet1 at which point its diameter subtended only #j4fi of a second of arc4 ,how small this quantity is may be appreciated from its taking more than ninety such lines laid side by side to make a width divisible by the eye4 ,such slenderness at the then distance of ,mars would correspond1 under the magnification commonly used1 only to three quarters of a mile4 ,theoretically1 then1 a line three quarters of a mile wide there should be visible to us4 ,practically1 both light and definition is lost in the telescope1 and it would be nearer the mark to consider in such case two miles as the limit of the perceptible4 ,with the planet nearer than this1 as is often the case1 the width which could be seen would be proportionally lessened4 ,perhaps we shall not be far astray if we put one mile as the limiting width which could be perceived on ,mars at present1 with distance at its least and definition at its best4 ,that so minute a quantity should be visible at all is due to the line having a sensible length and by summation of sensations causing to rise into consciousness what would otherwise be lost4 ,a stimulus too feeble to produce an effect upon a single retinal rod becomes recognizable when many in a row are similarly excited4 ,the experiment furnished another criterion1 of importance as regards the supposition that the lines on ,mars are illusory4 ,it showed that brain-begotten impressions of wires that did not exist could be told from the real thing when the wire subtended #j4fi of a second of arc or more2 that below this the outside stimulus was too weak to differ recognizably from optic effects otherwise produced2 while when the real wire was diminished to #j4ei1 it could not be seen at all4 ,now1 the majority of lines on ,mars so far recognized and mapped lie in strength of impression far above the superior limit of #j4fi4 ,to one versed in ,martian canal detection there is no possibility of self-deception in the case1 the canals being very much more salient objects to an expert than those who have not seen them suppose4 ,for it must not be imagined that1 when one knows what to be on the lookout for1 they are the difficult objects they seem to the tyro4 ,just as the satellites of ,mars were easily seen once they were discovered1 so with these lines4 ,a mile or two we may take1 then1 with safety as the smallest width for one of the lines4 ,the greatest was got by comparing what is by far the largest canal1 the ,nilosyrtis1 with the micrometer thread4 ,from such determination it appeared that this canal was from #be to #cj miles wide4 ,but it is questionable whether the ,nilosyrtis can properly be termed a canal1 so much does it exceed the rest4 ,it is certainly far larger than the majority of them4 ,from comparative estimates between its size and that of the others1 #ae to #bj miles for the width of the larger of the ,martian canals seems the most probable value1 and #b or #c miles only of the more diminutive of those so far detected4 ,illustration3 ,showing the ,eumenides-,orcus4 ,on the other hand1 the length of the canals is relatively enormous4 ,with them #bjjj miles is common2 while many exceed #bejj1 and the ,eumenides-,orcus is #cedj miles from the point where it leaves the ,phnix ,lake to the point where it enters the ,trivium ,charontis4 ,this means much more on ,mars than it would on ,earth1 owing to the smaller size of the planet4 ,such a length exceeds a third of the whole circumference of its globe at the equator4 ,but what is still more remarkable1 throughout the whole of the long course taken by the canal1 it swerves neither to the right nor to the left of the great circle joining the two points4 ,of these several peculiarities of the individual canal it is difficult to know to which to allot the palm for oddity1--great circle directness1 excessive length1 want of width1 or striking uniformity4 ,each is so anomalously unnatural as to have received the approving stamp of incredulity4 ,yet so much1 wonderful as it is1 is encountered on the very threshold of the subject4 ----- ,footnote #b3 ,m4 l'abb ,moreux4 ,footnote #c3 ,as some misrepresentation has been made on this subject through misapprehension of the writer's observations on ,venus and ,mercury1 it may be well to state that the tenuous markings on both these other planets entirely lack the unnatural regularity distinguishing the canals of ,mars4 ,the ,venusian lines are hazy1 ill-defined1 and non-uniform2 the ,mercurian broken and irregular1 suggesting cracks4 ,neither resemble the ,martian in marvelous precision1 and have never been called canals by the writer nor by ,schiaparelli1 but solely by those who have not seen them and have misapprehended their character and look4 ,,chapter ,,xvi ,,their ,,system ,much more stands beyond4 ,for1 outdoing in suggestiveness the individual traits of the lines1 is the relation shown by them to one another4 ,it is the communal characteristics of the phenomenon that are most surprising4 ,the individual peculiarities of the lines impress themselves at once2 the communal1 only as the result of experience1 collation1 and thought4 ,as the observer becomes trained1 the more lines he is able to make out1 until they fairly seam the whole surface of the light areas of the planet4 ,their name collectively is legion2 while to name them individually is fast getting1 for the number detected1 to be impossible4 ,as with the increasing family of asteroids1 figures alone will prove adequate to the task4 ,interdependence1 not independence1 marks the attitude of the canals4 ,each not only proceeds with absolute directness from one point to another1 but at its terminals it meets canals which have come there with like forthrightness from other far places upon the planet4 ,nor is it two only that thus come together at a common junction4 ,three1 four1 five1--up to as many as fourteen1--thus make rendezvous1 and it is a poor junction that cannot show at least six or seven4 ,the result is a network which triangulates the surface of the planet like a geodetic survey into polygons of all shapes and sizes1 the ,arian areolas4 ,the size of the pieces forming this tesselate ground depends solely upon the fineness of the definition4 ,with every increase in the power of seeing1 each areola is cut into still smaller portions1 usually by connection between its corners4 ,thus a polygon or rhombus is split into triangles which may themselves be divided in like manner1 the mosaic breaking into bits1 the sides of which1 however1 always remain clean-cut4 ,from this arrangement it is at once evident that the canals are not fortuitously placed4 ,that lines should thus meet exactly and in numbers at particular points1 and only there1 shows that their locating is not the outcome of chance4 ,if very thin rods be thrown haphazard over a surface1 the probability that more than two will cross at the same point is vanishingly small4 ,increasingly assured is it that this would not happen generally4 ,the result we see is therefore not a matter of chance1 but of some law working to that end4 ,to the detection of what that law is precedes the easier ascertainment of what it is not4 ,the lines1 for example1 cannot be rivers1 which was the first explanation offered of them by ,proctor many years ago1 because of their peculiar straightness4 ,nor can they be channels1 the name given to them by ,schiaparelli1 except in the non-committal sense in which he used the term4 ,for here again their geometric regularity is bar to any estuary-like hypothesis4 ,for quite another reason they cannot be cracks1 because of their uniform size throughout4 ,their unbroken character is another fatal objection to the same suggestion4 ,for cracks in ground never pursue for any great distance a continuous course1 any more than they keep uniform or straight4 ,the state of an old ceiling is a case in point4 ,when it breaks1 it does so in fissures that proceed a certain way1 then give out to be continued by others roughly parallel to the first1 but parted from them4 ,the same character is shown by the rills on the moon4 ,the #8,straight ,wall1' so called1 is composed of three such sections1 and the little rill to the right of it1 west of ,birt1 of four4 ,thus were they seen at ,flagstaff1 and as1 to the writer's knowledge1 they have not been so depicted elsewhere1 the fact may serve to give some idea of the definition there4 ,that the underlying cause is not explosion or contraction is also evidenced by the canals collectively as well as individually1 their arrangement into a system1 for cracks1 however produced1 could only originate from certain centres and could not fit into those starting from others1 as the canals invariably do4 ,for each canal goes as undeviatingly to one terminal as it left forthrightly from another4 ,if one wishes to see what explosion or contraction can do1 he has only to look at the moon through an opera-glass1 when he will be shown a very different sight from what the drawings of ,mars detail4 ,thus just as1 considered individually1 the lines cannot be watercourses because of their straightness1 so they cannot be cracks because of dovetailing into one another4 ,the fact that they form a system shows that whatever caused them operated over the whole planet1 linked in cause as in effect throughout each section4 ,this at once negatives any purely physical cause of which we have cognizance4 ,for upon a globe still so subject to physical vicissitude as ,mars by its aspect shows itself to be1 latitude must tell in the phenomena its zones exhibit4 ,polar snows that wax and wane speak of arctic conditions very diverse from temperate and tropic states1 and what would affect the one could not influence the other4 ,yet the mesh rises superior to zonal solicitation as to local barrier4 ,it is not something dependent either on the temperament or the complexion of the globe's different parts4 ,it transcends surface restriction and becomes planet-wide in its working4 ,the importance of this omnipresence dilates in meaning as one dwells in thought upon it4 ,ubiquitous as it is1 the mesh which thus covers the ,martian surface like a veil spread completely over it1 is unlike a veil in being of irregular texture4 ,not only are the interstices of various shape and pattern1 but the mesh itself is of locally differing size4 ,though the threads are straight and uniform throughout1 they are not all alike1 besides being unsymmetrically interwoven4 ,some are at least of ten times the coarseness of others1 and from this fact and the bo-peep effect of our air waves all are not visible at once4 ,in consequence the network is not so impressive at first glance as it becomes upon a synthesis of the observations4 ,when this is done1 the surface proves to be fairly evenly cut up1 as recourse to the maps printed in this volume will amply demonstrate4 ,these maps1 as on page #ca1 are made from the results of but one opposition1 and as at each opposition some zone is in a more canal-showing state than others1 owing to the ,martian season at the time1 a still greater uniformity in canal distribution results from a blending of many4 ,from the completeness of the mesh1 it follows that in the course taken severally by the canals no one direction preponderates over another4 ,considered by and large1 the canals seem to be equally distributed round the compass points2 and this at all longitudes and nearly all latitudes4 ,tropic1 temperate1 and even arctic canals show a pleasing impartiality in the matter of the course pursued4 ,the only exceptions occur in the neighborhood of the pole4 ,there a slight tendency may be seen to a north and south setting4 ,though so much is visible in a general way from the map1 it is of interest to go into the subject with more particularity and to that end to show it statistically4 ,the several canals traversing each zone were therefore counted1 and the area of the zone computed4 ,the manner of canal distribution thus found is given in the following table1 in the second column of which stand the areas of the several zones upon the planet1 each ten degrees wide1 except the one next the snow1 and in the third the number of canals found traversing them1 reduced to percentages of the #j-aj zone4 ,a fourth column shows the total length of the canals in each zone1 those from #j to #bj being taken from the #ahif globe1 those from #bj to #ij from the #aijc4 ,this is in order to annul the effect of the seasons upon the showing of the canals as much as possible4 ,,zone ,,area ,,no4 ,,of ,,canals ,,actual ,,length ,,wtd4 ---------------------------------------- -------------------- #j-aj #a4jj #a4jj #a4jj #aj-bj 4#ig 4#hi 4#ia #bj-cj 4#ia 4#ic 4#gb #cj-dj 4#hb 4#ij 4#ga #dj-ej 4#ga 4#gh 4#ff #ej-fj 4#eh 4#fd 4#ei #fj-gj 4#db 4#dc 4#db #gj-hj 4#bf 4#cj 4#cd #hj-he 4#jg 4#ab 4#aa ,the numbers continue fairly non-committal until we begin to approach the pole1 when they commence to increase4 ,much the same result is got if we take the actual canal-lengths in each zone1 as the fourth column shows4 ,the crowding of the canals poleward is marked4 ,the canals1 therefore1 are phenomena that stand in peculiar relationship to the polar cap4 ,this corroborates the inference about them due to their running out of the edge of the snow4 ,they not only emanate from it1 but they do so in numbers surpassing what is elsewhere observable over the disk4 ,otherwise is it with their departure-points4 ,these are not scattered haphazard over the surface1 but bear to its general features definite relations4 ,if we consider the map1 obliterating the lines1 and then seek to connect the most salient points of the planet's topography by direct avenues of communication1 we shall find that our putative lines fall exactly where the real ones occur4 ,for the most part1 the real lines emanate from well-marked indentations in the dark regions1 fitted by natural position for departure-points1 what1 if these were seas1 we should call their most conspicuous bays4 ,they thus leave in the southern hemisphere the deeper folds of the great diaphragm1 for the most part2 though on occasion they run out of them where they will4 ,from equally conspicuous points in the dark northern areas other lines proceed2 while in the centre of the continents1 the canals make for more or less salient spots1 small patches of shading like the ,trivium or the ,wedge of ,casius1 or simply round black radiants1 like the ,luci ,ismenii4 ,from this it appears that the lines are locally dependent upon the general topography of the fundamental features of the surface4 ,for some reason they connect the very points most suggestive of intercommunication4 ,as from their characteristics it is perfectly evident that the lines are neither rivers nor cracks1 it follows that such a communicating habit is of the most telltale character4 ,to be so dissimilar in kind from the main markings and yet so dependent upon them1 hints that their positioning occurred after the formation of the main features themselves4 ,we reach thus from the look of the lines and their location a most striking deduction1 that the lines are not coeval with the main markings1 but have come into being later and with reference to the general topography of the planet4 ,the network is not only a mesh de facto1 then1 but one de jure1 which1 subsequent to the fashioning of the seas and continents and what these have now become1 has been superposed upon them4 ,,chapter ,,xvii ,,gemination ,,of ,,the ,,canals ,fraught with more difficulty than the detection of the lines alone is the next discovery made upon the disk3 the recognition of pairs of lines traversing it4 ,in #ahgi1 while ,schiaparelli was engaged in scrutinizing the strange canali he had discovered on the planet the opposition before1 he was suddenly surprised to mark one of them double4 ,two closely parallel lines confronted him where but a single one had previously stood4 ,so unaccountable did the sight seem1 that he hesitated to credit what he saw1 being minded to attribute the vision to illusion of some sort and the more so that it was not renewed4 ,while he was still wondering what it meant1 the planet parted company with the ,earth1 carrying its enigma with it4 ,when the two bodies again drew near to one another in #ahhb1 ,schiaparelli set himself to watch for a recurrence of the strange phenomenon4 ,before long it came1 and more bewilderingly than at first2 for not one canal alone1 but a score of them now showed in duplicate1 each presenting to his astonished gaze twin lines perfectly matched and preserving throughout their distance apart4 ,suspecting diplopia or some other optical trick1 he tried various eyepieces to a test of the cause but to no change in the effect4 ,the twin lines continued visible1 do what he would1 insisting on their own reality in spite of all solicitation to merge4 ,how cautious he was in the matter1 and how unwilling at first to believe the evidence of his eyes1 is shown by the care he took to guard against deception4 ,it was not until he had assured himself of the reality of the phenomena that he believed what he had seen4 ,it so chanced that my first experience of the thing was almost equally startling1 so unexpected was it and so exceedingly sharp was the definition at the time4 ,it was in an autumn early twilight1 through air almost perfectly still1 as the light went out of the sky and the markings on the planet began to come forth that the ,phison of a sudden showed in duplicate to me1 clear-cut upon the disk1 its twin lines like the rails of a railway track traversing ,aeria4 ,not more vivid do those of our transcontinental tracks appear as one sees them stretching off into the distance upon our ,western plains4 ,more impressive was the sight from the fact that ,i was not looking for it4 ,it simply suddenly stood forth1 this strange parallelism of pencil lines4 ,my surprise matched the wonder of the sight4 ,since then ,i have witnessed it several hundred times1 but never with more absolute certainty than at that first fortunate revelation4 ,to this distinctness is due the amazement it then aroused4 ,not simply because of its surpassing novelty1 but for the insistence with which it proclaimed itself was the effect to be ascribed4 ,less well seen1 doubt had robbed it of its full surprise4 ,it requires as a rule steady definition for its initial unmistakable showing1 if one would be instantly convinced4 ,except for such it is not usually easy to the unpracticed1 though often discernible to the expert after it has once been seen4 ,but that it is real no one who had had a good view of the sight could doubt2 still less after the experience had been repeated over and over again4 ,what appears to take place is this3 where previously a single pencil-like line joined two well-known points upon the disk1 twin lines1 the one the replica of the other1 stand forth in its stead4 ,the two lines of the pair are but a short distance apart1 are of the same size1 of the same length1 and absolutely equidistant throughout their course4 ,it is as if a second line had in some way been mysteriously added to the first since the latter was last seen some weeks before4 ,this in a word is the phenomenon1 technically called the gemination of the canals1 which has since its discovery called forth so much comment4 ,it is not in reality quite as simple or as sudden as it seems1 but this was the way in which the phenomenon was first seen and in which it still continues to be criticised4 ,self-assertive of reality1 the double lines are patently objective to him who is fortunate enough to see them well4 ,nevertheless the great difficulty of detecting them1 and the still greater difficulty of conceiving how such things can be1 has led many not versed in the subject to disbelieve and from that to attempt to explain the sight as illusory4 ,scepticism seeks self-justification2 what is hard of acceptance for its strangeness begetting hypotheses of committed error which find easy credence for their comforting conservatism4 ,several such have in consequence been propounded to account for the double canals4 ,there is the diplopic theory which credits them to non-focusing2 the interferential theory which would make them optical products of the telescope2 and the illusion theory which would have them quite simply imaginary4 ,inasmuch as in any research the assurance that a phenomenon is real is the first point about it to be established1 it is a scientist's duty1 not only to scan the phenomena with jealous care to that end1 but to scrutinize every theory which would seek otherwise to account for them--the testing such being only second in importance to observing the things themselves4 ,accordingly ,i have examined each of the optical theories that have been advanced and critically compared what they assert and require with the results of observation4 ,the outcome of this research has proved as negativing to any other origin for the double canals than reality as direct observations at the telescope are positive on the point4 ,to show this ,i shall review each in its consequences1 confronting it with what the telescope has to say on the subject2 for it is of the pith of the matter that the reality should be as demonstrable on demand as on sight4 ,furthermore1 ,i shall do this before embarking on the general account of these strange things1 because it is vital to any interest that one should be assured from the start of the truth of what he is to read4 ,the preface may seem to him abstruse and prosy1 but it will introduce him to some curious optical properties and will eventually enhance his concern by proving to him that what reads like fiction is all the more wonderful for being fact4 ,i4 ,the ,diplopic ,theory ,diplopia is the property of seeing double with one eye4 ,surprising as it sounds it is an effect not unknown to students of optics1 though it usually requires training to produce4 ,it is possible only when the eye is not focused on the object1 and is not always possible then4 ,from my experiments its feasibility seems to depend upon whether the focus be beyond or before what it should be4 ,if the eye be focused for a point beyond the object1 the object is doubled1 if for a point this side of it1 the latter is simply blurred4 ,when the double is formed1 the amount of the separation of the two images is a function of the distance the focus is out4 ,the greater the discrepancy1 the wider apart is the ensuing double4 ,nor does the image1 of a line1 for example1 stop at doubling4 ,after a certain breadth of separation is reached a third line appears1 bisecting the interval between the other two4 ,with yet greater widening the third line itself splits into a pair and so the resolution goes on4 ,in my own experiments ,i have gone so far as to suspect a fifth line4 ,far from being unconscious1 the process of producing the phenomenon is1 with some people1 of difficult accomplishment4 ,mr4 ,lampland1 for instance1 of the ,flagstaff ,observatory1 to whom we owe the first photographing of the canals1 and who sees the doubles of ,mars without difficulty1 has hitherto found diplopic vision an impossible feat4 ,even with the most practiced diplopia is never unconscious except when the object viewed1 as a micrometer wire1 has nothing to locate it in space4 ,now1 the diplopic theory of the double canals supposes that in all cases the eye of the observer is thus unconsciously out of focus4 ,to this method of their manufacture the telescopic phenomena prove unamenable on five counts4 #a4 ,focusing the eye on an object is now a reflex action1 so automatic has it become2 in consequence one is commonly directly conscious when an object is not in focus1 always so when the object presents detail4 ,were such not the case we should never1 except by chance1 see anything defined4 ,observing through a telescope1 after a modicum of practice1 differs in no respect from observing in everyday life4 ,consequently1 that an experienced observer should not know his business in so primary a matter is preposterous4 ,one may or may not believe that 8the undevout astronomer is mad10 but that the perpetually unfocused one would be is beyond debate4 #b4 ,generically unlikely1 the failure to focus is here specifically out of the question4 ,for the observer does not use the canals to focus on for the simple reason that he cannot4 ,like all delicate detail1 the doubles appear not continuously but by flashes of revelation1 according as the atmospheric waves permit of passage undisturbed4 ,to focus on them would be next to impossible even were it resorted to--which it never is4 ,by the exponents of the theory this important fact is overlooked3 the unforeseen showing of the canals and therefore the absolute lack of complicity of the eye in the matter4 ,what one focuses on is the look of the main markings of the disk4 ,now1 to suppose an observer systematically out in his perceptions of so featureful a planet as that of ,mars1 so that he does not know when he sees its image sharp1 implies a lack of knowledge of astronomic observation in the supposer4 #c4 ,study by the writer shows the width of a given double canal to be constant for a given date4 ,within the errors of perception or recording the twin lines are always at the same epoch the same distance apart4 ,the greater the number of determinations made1 the nearer the result approaches to this mean2 and the greater the care used in delineation1 the less each value departs from it4 ,now1 if the thing were a matter of mistaken focusing1 an eye could not be thus true to its own mistakes4 ,if it were out in its focus by a certain amount at one time1 it would be likely to be out by a different amount at another4 ,so that by the very terms of its making a diplopic double would be sure to vary4 ,indeed1 in laboratory experiments it is impossible to prevent it4 ,for the eye rests itself automatically by change of focus1 and if it be not consciously kept awry it reverts as near to the true focus as it can of its own accord4 #d4 ,diplopia might be a respecter of persons1 but it certainly could not be one of canals4 ,for a given observer it must be objectively general in its application to the same class of objects4 ,consequently1 if the doubling were diplopic1 all canals inclined at the same angle to the vertical--for the tilt might affect the result were the eye astigmatic--should be similarly affected4 ,parallel canals should parallel each other's action4 ,with the ,martian doubles this is not the case4 ,of two canals similarly inclined the one will be double1 the other not1 at the same instant and under conditions that are alike4 ,and this persistently4 ,for gemination is an attribute of certain canals and never of others4 ,at a given season of the ,martian year1 some canals are regularly double1 some invariably single4 ,night after night and presentation after presentation these idiosyncrasies are preserved3 the doubles1 always pairs1 the single1 always alone4 ,nor does the strength of the line affect the action4 ,the single canals are some of them stronger1 some of them weaker1 than the doubles seen at the same time4 #e4 ,if of diplopic origin the mean width of all the doubles should be the same4 ,for though the diplopic width would vary for a given canal according to the moment1 a sufficient number of views would yield a mean width which would be the same for all4 ,tilt apart1 the mean width of one canal would be that of another4 ,among ,martian doubles1 on the contrary1 ,i have found the width to be a specific property of the particular canal4 ,each has its own mean width regardless of inclination1 and this individual width differs as between one and another by as much as five to two1 or1 if we consider such canals as the ,nilokeras ,i and ,,ii1 by more than ten to two4 ,any one of these five points is fatal to the theory2 a fortiori all4 ,,ii4 ,the ,interference ,theory ,from the wave propagation of light it follows that the image of a bright line made by a lens is not itself a simple bright line but a bright band flanked by alternate dark and bright ones4 ,it has1 therefore1 been suggested that a bright medial line is here concerned and that the double canal is the first of its dark pair of outriders4 ,but the suggestion does not bear scrutiny4 #a4 ,it presupposes a central streak brighter than the rest of the disk to give birth to the twin dark lines4 ,this should itself be visible in the image2 but no such bright backbone is seen4 #b4 ,it demands a perfectly definite width of separation for a given aperture--which is not that observed4 #c4 ,it makes the width a function of the aperture1 decreasing as this increases--which is not sustained by observation4 ,different apertures produce no effect on the widths of the ,martian doubles1 as the writer has shown 7,lowell ,observatory ,bulletin1 ,no4 #e7 by a change of aperture from twenty-four to six inches4 #d4 ,under like optical conditions the optically produced doubles would be all of a width2 while the ,martian ones show idiosyncratic widths1 each peculiar to itself4 ,,iii4 ,the ,illusion ,theory ,known also as the ,small ,boy ,theory from the ingenuous simplicity on which it rests1 this theory attacks the reality of the doubles by questioning that of the canals en bloc4 ,because some boys from the ,greenwich 7,reform or7 ,charity ,school1 set to copy a canal-expurgated picture of the planet1 themselves supplied the lines which had preceptorily been left out1 the ,martian canals have been denied existence2 which is like saying that because a man may see stars without scanning the heavens1 therefore those in the sky do not exist4 ,as to the instructions the boys received we are left in the dark4 ,it looks as if some leading questions had unconsciously been put to them4 ,at all events1 ,english charity boys would seem to be particularly pliant to such imagination1 for when ,flammarion retried the experiment with ,french schoolboys1 and even inserted spaced dots for the canals in the copy1 not a boy of them drew an illusory line4 ,the fact is1 this is one of those deceptive half-truths which is so much more deleterious than an unmitigated mistake4 ,under certain circumstances it is quite possible to perceive illusory lines1 due either to shadings otherwise unmarked and thus synthesized or to immediately precedent retinal impressions transferred to places where they do not belong by rapid motion of the eye1 as ,i had myself discovered before the ,english experiment had been tried4 ,but1 as ,i have also found out1 these effects are produced only at the limit of vision1 and in that limbo of uncertainty the whole art of the observer consists in learning to distinguish the true from the false4 ,strength of impression1 renewed effect in situ1 and a peculiar sense of reality or the reverse enable him to adjudge the two4 ,more experience than the boys possessed would have helped them to part the sheep from the goats4 ,but1 furthermore1 and fatally to the theory here in question1 the ,martian canals when well seen are not at the limit of vision as its framers supposed1 but well within that boundary of doubt2 so that the premise upon which the whole theory rests gives way4 ,under good atmospheric conditions the canals are comparable for conspicuousness to many of the well-recognized ,fraunhofer lines and are just as certainly there4 ,thus each attempt to prove the doubles non-objective turns out when specifically examined to be inconsistent with the facts4 ,with the assurance of their reality thus made doubly sure1 we pass to consideration of the things themselves4 ,,chapter ,,xviii ,,the ,,double ,,canals ,i ,rightly viewed1 no more subtle tribute could be paid to the remarkable character of the phenomenon of gemination than the scepticism with which it was immediately received and which it still continues to elicit4 ,that the sight should be regarded as illusory speaks for its surpassing strangeness2 and so far as oddity goes the encomium is certainly deserved4 ,of the bizarre features of this curiously marked disk1 the double canals were at the time of their discovery the culmination1 and though things stranger still if possible have since been seen there1 it is not wonderful that doubt should still incredulously stare4 ,if the mere account of them reads like romance1 to see them is an experience4 ,nothing astronomical that ,i have ever seen has been so startlingly impressive as my first view of a double canal4 ,even in narration the thing justifies its effect4 ,for a double canal consists of a pair of twin dark filaments1 perfectly parallel throughout their course and inclosing between them ground of the same ochreish cast as that which lies without4 ,only on occasion is this tint of their midway departed from1 and then only toward a darkening1 never toward a lightening of it4 ,except for appearing paired1 the lines resemble precisely the usual single canals4 ,in length they vary from a few hundred to a few thousand miles1 while in width each component1 for narrowness1 hardly permits of definite ascription4 ,compared for strength with the usual canal the lines of a double seem to hold on the average an intermediate position between the larger and the smaller of the single canals so far detected4 ,owing1 however1 to the massed effect of the pair by reason of their closeness1 they have an advantage in showing over the singles of two to one4 ,and this renders them among the most conspicuous and important meshes of the canal network4 ,like the single canals1 they vary in strength with the ,martian time of year2 at certain seasons developing into heavy pencil lines and at others fading away to the merest gossamers1 only just discernible like cobwebs stretched across the face of the planet4 ,although the individual constituent lines vary in aspect and never rise at their most to cognizable breadth1 the distance parting their centres1 or the width of the double1 is quite measurable4 ,the only difficulty in the way of its determination lies in the absence of a procurable unit small enough to mete it4 ,the usual spider-threads of the micrometer are colossal in comparison with these filaments and present a standard only analogic at best4 ,nevertheless1 by means of the finest threads that could be got1 estimates of the distance between the pairs were made at ,flagstaff in #aije1 and the results agree as closely as the means permit with those got by measurement of the doubles as depicted in the drawings4 ,illustration3 ,martian doubles4 ,of what they look like1 the following illustrations give a fair idea1 only that instead of being more geometrically regular in the drawing than in reality the fact is the other way4 ,freehand draftsmanship at the telescope is incapable of rendering their ruled effect4 ,no railway metals could be laid down with more precision4 ,as to their size1 the following figures derived from a typical double canal1 the ,phison1 give some conception4 ,this great artery of intercommunication between the ,sabaeus ,sinus and the ,nilosyrtis is1 roughly speaking1 #bbej miles long2 the distance between the centres of the two constituents is about #acj miles1 and each line is perhaps #bj miles in breadth1 when at its maximum strength4 ,the pair follow1 apparently1 the arc of a great circle from the ,portus ,sigaeus on the ,mare ,icarium to the ,pseboas ,lucus in latitude #dj north4 ,the ,portus ,sigaeus consists of two little nicks in the coastline1 looking like the carets one makes in checking off items down a list1 if the space between the down and up strokes were then filled in2 the ,pseboas ,lucus1 on the other hand1 is a large round dot like a small ink spot4 ,to these two differently appearing spots1 the twin lines of the ,phison behave differently4 ,while each line leaves centrally its own caret of the ,portus ,sigaeus at the south1 at the north each touches peripherally the ,pseboas ,lucus1 on the east and west sides respectively1 the two thus just holding the ,lucus between them4 ,in position the lines are invariable1 though in visibility not4 ,sometimes only one is seen1 sometimes both show faintly1 and sometimes both are conspicuously strong4 ,the delicacy of the observations by which this detail was established is second only to its importance4 ,it destroys at a stroke all possibility of diplopic unreality1 since were that the fact the ,pseboas ,lucus should be doubled1 which it is not4 ,at the same time it opens vistas into the true construction of the things themselves1 at present more suggestive than satisfactory4 ,illustration3 ,martian doubles 7corroborating the above74 ,in the great circle character of its course the ,phison is quite normal4 ,the majority of the double canals pursue the like method1 running straight over the surface from one point to another1 the constituents remaining equidistant throughout4 ,but such forthrightness of direction1 though the rule1 is not without exceptions4 ,the ,thoth-,nepenthes1 for example1 sweeps round in a seemingly continuous curve to the west-southwest from the ,aquae ,calidae to the ,lucus ,moeris like some mighty bow perpetually bent4 ,nevertheless its lines are no less careful for all their curving to keep their distance from one end to the other of their course4 ,the quality of being paired rises superior to change of direction4 ,,ii ,now1 the first point to be noticed about the doubles is that bilateralism1 or the quality of being double1 is not a universal trait of the canals1 either actually or potentially2 it is not even a general one4 ,out of the four hundred canals seen at ,flagstaff1 only fifty-one have at any time displayed the quality2 that is1 one eighth roughly of the whole number observed4 ,this point is most important2 for the fact is of itself enough to disprove any optical origin for the phenomenon4 ,the characteristic of doubling so confidently ascribed by those who have not seen it to general optical or ocular principles proves thus the exception1 not the rule1 with the canals1 and by so doing disowns the applicability of any merely optical solution4 ,we shall encounter many more equally prohibitive bars to illusory explanation before we have done with the doubles1 but it is interesting to meet one in this manner at the very threshold of the subject4 ,on the other hand1 the characteristic when possessed is persistent in the particular canal1 in posse if not in esse4 ,once shown by a canal1 that canal may confidently be looked to at a proper time to disclose it again4 ,in short1 bilateralism1 or the state of being dual1 is an inherent attribute of the individual canal1 as idiosyncratic to it as position and size4 ,the catalogue of canals possessing this property1 so far as they have been detected at ,flagstaff to date1 number fifty-one if we include in the list wide parallels like the ,nilokeras ,i and ,,ii4 ,eight of these were observed in #ahid2 nineteen more were added in #ahif1 making twenty-seven2 in #aija the total was raised to thirty2 in #aijc to forty-eight2 and in #aije to fifty-one4 ,arranged by years they are tabulated below1 where the numeral to the left registers for each its first recording and the position held by it in the list4 ,the starred canals much exceed the others in width1 and possibly denote a different phenomenon4 ,,date ,,confused #ahid #a4 ,ganges #b4 ,nectar #c4 ,euphrates #d4 99,nilokeras ,i and ,,ii #e4 ,phison #f4 ,asopus #g4 ,jamuna #h4 ,typhon #ahif-g ,ganges ,typhon ,euphrates ,avernus ,s4 ,phison #i4 ,lethes ,jamuna #aj4 ,dis ,s4 #aa4 ,titan #ab4 ,laestrygon #ac4 ,tartarus #ad4 ,cocytus #ae4 ,sitacus #af4 ,amenthes #ag4 ,adamas #ah4 ,cerberus ,n4 #ai4 ,cerberus ,s4 #bj4 ,cyclops #ba4 ,gelbes #bb4 ,erebus #bc4 ,avernus ,n4 #bd4 ,gigas #be4 ,alander #bf4 ,gihon #bg4 ,hiddekel #aijj-a ,phison ,dis ,s4 ,euphrates ,boreas ,hiddekel ,cerberus ,s4 ,amenthes ,jamuna ,cerberus ,n4 ,pyramus ,cyclops ,laestrygon ,ganges #bh4 ,deuteronilus ,sitacus ,adamas #bi4 ,djihoun ,gihon #cj4 ,is #aijc ,djihoun ,typhon ,hiddekel ,orontes ,phison ,euphrates #ca4 ,protonilus ,gihon #cb4 ,marsias ,amenthes ,laestrygon ,cyclops ,gigas 99,nilokeras ,i and ,,ii ,ganges ,deuteronilus #cc4 ,pierius #cd4 ,callirrhoe ,jamuna ,sitacus #ce4 ,astaboras ,s4 #cf4 ,nar #cg4 ,chaos #ch4 ,aethiops #ci4 ,hyblaeus #dj4 ,eunostos #da4 ,thoth #db4 ,nepenthes #dc4 ,triton #dd4 ,pyramus #de4 ,fretum ,anian #df4 ,vexillum ,lethes ,cerberus ,s4 #dg4 ,nilokeras ,i ,cerberus ,n4 #dh4 ,tithonius #aije ,nilokeras ,ganges ,hiddekel ,chrysorrhoas ,djihoun ,sitacus ,phison ,euphrates ,amenthes ,vexillum ,astaboras ,s4 ,adamas ,cyclops ,cerberus ,s4 ,cerberus ,n4 ,tartarus #di4 99,propontis ,gigas ,gihon ,nepenthes ,thoth ,laestrygon #ej4 ,polyphemus ,deuteronilus ,triton ,eunostos ,tithonius ,callirrhoe ,pyramus ,nar ,protonilus #ea4 ,naarmalcha ,in spite of possessing the property of pairing1 a canal may not always exhibit it4 ,to the production of the phenomenon the proper time is as essential as the property itself4 ,so far as a primary scanning or first approximation is capable of revealing1 a canal will be single at one ,martian season and double at another4 ,thus these canals alternated in their state to ,schiaparelli and for the earlier of his own observed oppositions to the writer4 ,in consequence ,schiaparelli deemed gemination a process which the canal periodically underwent4 ,three stages in the development were to him distinguishable3 the single aspect1 a short confused aspect1 and the clearly dual one4 ,in the single state the canal remained most of the time4 ,it then underwent a chrysalid stage of confusion to emerge of a sudden into a perfect pair4 ,furthermore1 he noted the times at which the pairing took place1 to the formulating of a law in the case--derived from the observations of more than one opposition4 ,his law was that the gemination occurred1 on the average1 three months 7ours7 after the summer solstice of the northern hemisphere1 lasted four to five months1 then faded out to begin afresh one month after the vernal equinox of the same hemisphere and continue for four months more4 ,expressed in ,martian seasonal chronology1 the periods would be about half as long4 ,at certain times then the most pronounced specimens of doubles showed obstinately single1 while the periodic metamorphosis that transformed them into duplicates was timed to the changes of the planet's year4 ,gemination1 then1 was a seasonal phenomenon4 ,advance in our knowledge of the phenomenon since ,schiaparelli's time1 while still showing the thing to be of seasonal habit1 has changed our conception of it4 ,it now appears that in some cases certainly1 and possibly in all1 the dual aspect is not a temporary condition1 but the differing pronouncement of a permanent state1 the fact of gemination so called being confined to a filling out of what is always skeletonly there4 ,as the canals have come to be better seen1 the three stages of existence have in some cases become recognizable as only different degrees in discernment of an essential double condition2 the single appearance being due to the relative feebleness of one of the constituents and the confused showing to the weakness of both1 which are then the more easily blurred by the air waves4 ,in certain canals the last few oppositions1 #aija1 #aijc1 and #aije1 have disclosed this unmistakably to be the case1 as with the ,phison and ,euphrates1 for example4 ,with them the double character has been continuously visible1 appearing not only when by ,schiaparelli's law it should1 but at the times when it should not2 only on these latter occasions it was harder to see1 whence the reason it was previously missed4 ,so that further scrutiny1 while in no sense discrediting the earlier observations1 has extended to them some modification1 and disclosed the underlying truth to be the varying visibility1 the thing itself1 except for strength in part or whole1 persisting the same4 ,improvement in definition has lowered the see-level to revelation of continuous presence of the dual state4 ,it is only on occasion that the improvement is sufficient for the thing when at its feeblest to loom thus above the horizon of certainty2 yet at such moments of a rise in the seeing it is enough to allow it to be glimpsed4 ,thus it fared with the ,adamas at the opposition of #aijc1 with the ,gigas1 and with many another in years gone by4 ,separation has come with training and generally in the case of the wider doubles1 which leads one to infer that ease of resolution is largely responsible for assurance of the permanency of the dual state4 ,perplexing exceptions1 however1 remain1 so that it is possible at present only to predicate the principal of most of the double canals but not of all4 ,leaving the exceptions out of account for the moment1 we pass to those general characteristics which are intimately linked with what has just been said4 ,inasmuch as the act of getting into a state antedates the fact of being there1 it is logical to let the description of the first precede4 ,an account of the process of gemination may thus suitably come before that of its result4 ,flux1 affecting the double canals in whole or part1 is the cause of the apparent gemination4 ,according as the flux is partitive or total is a single or a dual state produced4 ,at the depth of its inconspicuousness the canal may cease to be visible at all2 this occurs when both lines fade out4 ,on the other hand1 the one line may outfade the other1 and we are presented with a seemingly single canal1 at this its minimum showing4 ,in such seasons of debility the one line may appear and the other not1 or occasionally the other show and the one not1 according to the air waves of the moment4 ,it is at these times that the double simulates a single canal1 and unless well seen and carefully watched might easily masquerade successfully as such4 ,the ,hiddekel in the depth of its dead season is peculiarly given to this alternately partitive presentation4 ,as the flux comes on1 one or both lines feel it4 ,if one only we are likely to have a confused canal2 if both1 a difficult double4 ,the strength of the lines increases until at last both attain their maximum1 and the canal stands revealed an unmistakable pair1 the two lines paralleling one another in appearance as in position4 ,at the canal's maximum and minimum the equality of its two constituents is chiefly to be remarked1 though it occurs on other occasions as well4 ,but1 what is significant1 when the two differ it is always the same one that outdoes its fellow4 ,it may be the right-hand twin in one pair1 the left-hand one in another2 but whichever it be1 for the particular canal its preminence is invariable4 ,it is this canal which1 except for adventitious help or hindrance from the air-waves1 alone shows when the double assumes the seemingly single state4 ,we may therefore call it the original canal1 the other being dubbed the duplicate4 ,in some cases it has been possible to decide which is which4 ,it might seem at first sight as if this point should always be ascertainable4 ,but the determination is more dilemmic than appears1 not from any difficulty in seeing the canal1 but from the absence of distinguishing earmark at its end4 ,in a long stretch of commonplace coast1 the precise point of embouchure of a solitary canal cannot be so certainly fixed as to be decisive later between two which show close together in the same locality4 ,it is only where some landmark points the canal's terminal that the problem admits of definite solution4 ,this telltale tag may be a bay like the ,margaritifer ,sinus1 or double gulfs like the ,sabaeus ,sinus1 or portions of a marking not too large to permit of partitive location like the ,mare ,acidalium1 or a canal connection like the ,tacazze which prolongs the one line and not the other4 ,in these and similar instances the two lines become capable of identification1 and in such manner have been found those comprised in the following list3-- ,,date ,,of ,,double ,,canal ,,original ,,line ,,ascertainment ---------------------------------------- -------------- ,phison ,the ,eastern #ahid ,euphrates ,the ,western #ahid ,titan ,the ,western #ahif ,hiddekel ,the ,eastern #ahif ,gihon ,the ,western #ahif ,gigas ,the ,northwestern #ahif ,djihoun ,the ,western #aija ,laestrygon ,the ,eastern #aijc ,nilokeras ,i and ,,ii ,the ,northern #aijc ,astaboras ,the ,southern #aijc ,jamuna ,the ,eastern #aije ,ganges ,the ,western #aije ,in this list of originals the canals stand chronologically marshaled according to date of detection4 ,the ,phison and ,euphrates were the first to permit of intertwin identification in #ahid1 while the ,jamuna and ,ganges were the last to be added to the column in #aije4 ,the list is not long1 though the time taken to compile it was4 ,in the case of the ,ganges and the ,jamuna1 for example1 although suspected for some time on theoretic grounds1 it was only at the opposition just passed that the fact was observationally established4 ,in his ,memoria ,v1 ,schiaparelli has a list of similar detection1 and if the present list be compared with his1 the two having been independently made1 the concordance of the result will prove striking1 corroborative as it is of both4 ,for the necessary observations are very difficult4 ,having thus realized the original by means of its superior showing1 and then identified it by its position1 it is suggestive to discover that the duplicate betrays its subordinate character1 not only by its relative insignificance1 but by its secondary position as well4 ,the original always takes its departure from some well-marked bay1 seemingly designated by nature as a departure-point1 or from a caret belonging clearly to itself2 the adjunct1 on the other hand1 leaves from some neighboring undistinguished spot1 as in the case of the additional ,djihoun1 or makes use of a neighbor's caret1 as in the case of the second ,phison and the supplementary ,euphrates4 ,in either case it plays something of the part of an afterthought2 and yet the postscript when finished reads as an integral part of the letter4 ,an example will serve to make the connection evident while leaving the character of the connection as cryptic as ever4 ,in the long stretch of ,aerial coastline bounding the ,mare ,icarium1 which sweeps with the curve of a foretime beach from the ,hammonis ,cornu to the tip of the ,edom ,promontory1 there stand halfway down its far-away seeming sea-front two little nicks or indentations4 ,even in poor seeing they serve to darken this part of the coast while in good definition they come out as miniature caret-like bays4 ,they are the ,portus ,sigaei1 and mark the spots where the ,phison and the ,euphrates respectively leave the coast4 ,about four degrees apart1 the eastern makes embouchure to the original ,phison1 the western to the original ,euphrates1 and each in some mysterious manner is associated not only in position but in action with the canal itself4 ,in the single state each canal leaves the ,mare from this its own caret1 the ,phison proceeding thence northeast down the disk1 the ,euphrates nearly due north1 so that starting four degrees apart at the south they are forty degrees asunder at their northern termini4 ,clearly at these latter points they are not even neighbors1 and except for the accident of close approach at their other ends have nothing in common anywhere4 ,and yet when gemination takes place a curious thing occurs3 each borrows its neighbor's terminal as departure-point for its own duplicate canal4 ,having thus got its base the replica proceeds to parallel its own original canal without the least reference to the other canal whose own caret it has so cuckoo-wise appropriated4 ,what the ,phison thus does to the ,euphrates1 the ,euphrates returns the compliment by doing to the ,phison4 ,in this manner is produced an interrelation which suggests1 without necessarily being1 an original community of interest2 suggests it on its face and yet appears to be rather of the nature of an adaptation to subsequent purposes of a something aboriginally there4 ,illustration3 ,mouths of ,euphrates and ,phison4 ,june4 #aijc4 ,that such latter-day appropriation is the fact is clearly hinted by the behavior of another understudy of an original canal1 in this case the duplicate of the ,djihoun1 which in consequence of the position of its original finds no neighboring embouchure already convenient to its use4 ,the single or original ,djihoun leaves the tip of the needle-pointed ,margaritifer ,sinus1 which serves a like end to the ,oxus and the ,indus1 both single canals4 ,the ,sinus is itself a single bay1 and so large that for many degrees its shores on both sides converge smoothly to their sharp apex4 ,because of this probably1 the coast in the immediate neighborhood is without canal connection1 no canal being known along either side till one reaches the ,hydraotes at the ,aromaticum ,promontorium1 which marks the western limit of the gulf4 ,the consequence is that when the ,djihoun doubles1 the duplicate canal1 not having any terminus ready to its hand1 has to make one for itself by simply running into the ,margaritifer ,sinus1 some distance up its eastern side4 ,it thus advertises its adjunctival character1 and at the same time the general fact that a neighbor's terminus1 though used from preference1 when convenient1 is not an essential in the process4 ,gemination occurs of its own initiative1 but is conditioned by convenience4 ,whether one canal shows thus to the exclusion of the other1 or whether both stand so confused as not to be told apart1 the fact remains that the double is not always recognizable as such4 ,if we turn to the list of the doubles on page #bbb1 we shall note that the same canals were not always seen in the dual condition at successive oppositions4 ,some1 indeed1 are so emphatically of the habit as to appear year after year in a paired state1 but others are not so constant to their possibilities4 ,now1 when it is remembered that at different oppositions we view ,mars at diverse seasons of its tropical year1 we see that this means that the phenomenon is seasonal2 and furthermore that its exhibition depends upon the canal's position4 ,gemination1 like the showing or non-showing of the single canal1 is conditioned by the place of the canal upon the planet4 ,,iii ,turning from such generic characteristics to more specific traits1 the first thing to strike an attentive observer is that the doubles differ in width2 that they are not mensurably alike in the property they hold in common of being paired4 ,in some the twin lines are obviously farther apart than in others1 and the relation persists however repeated the observations4 ,of two doubles the one will always surpass its fellow4 ,this contrasted individuality first struck me in the ,phison and the ,euphrates2 and from the first moment at which these doubles showed as such4 ,the ,phison pair seemed perceptibly the narrower of the two4 ,a like distinction was evident at the next opposition and the next2 in fact1 at every succeeding one to the present day4 ,nor was the recognition of the fact confined to me4 ,if we turn to ,schiaparelli's ,memoriae we shall find that that master had registered the same idiomatic width for the two canals from first to last throughout his long series of records4 ,the observation thus made proved to apply to each and all of these curious twins4 ,diversity in width for different doubles appears plainly in drawings where more than one double is depicted4 ,as an example1 two drawings are here given in the text1 made1 the one on ,july #ac1 #aije1 #ae1 and the other on ,july #bj1 #cac4 ,in them the ,phison1 ,euphrates1 ,djihoun1 and ,thoth appear contrasted as unmistakably as either of them does with the single canals apparent at the same time4 ,that this drawing is typical is borne out by all the best measures of the several doubles as seen at successive oppositions1 and marshaled in the subjoined list4 ,how truly individual the quality is stands proved by the relative values in different years which are even more accordant than the absolute ones4 ,the canals were3-- ,,width ------------------- #aijc #aije ,,mean ---------------------------------------- -- #a4 ,phison #c4e #c4d #c4d #b4 ,euphrates #d4j #d4b #d4a #c4 99,protonilus #b4h #b4j #b4d #d4 ,deuteronilus #b4b #b4d #b4c #e4 ,pierius #b4e -- #b4e #f4 ,callirrhoe #b4e 99#b4a #b4c #g4 99,hiddekel #c4h #d4i #d4c #h4 99,gihon #c4i #d4i #d4d #i4 ,djihoun #b4j #a4i #a4i #aj4 ,sitacus #c4h 99#c4c #c4f #aa4 ,jamuna #d4e -- #d4e #ab4 ,ganges #e4j #e4b #e4a #ac4 ,nilokeras ,i and ,,ii #aa4j #aa4g #aa4c #ad4 ,nilokeras ,i #b4c -- #b4c #ae4 ,gigas #c4e -- #c4e #af4 ,laestrygon #b4b -- #b4b #ag4 ,cerberus ,n4 #d4j -- #d4j #ah4 ,cerberus ,s4 #d4j -- #d4j #ai4 ,cyclops #b4i 99#b4b #b4f #bj4 ,nar #b4f #b4j #b4c #ba4 ,fretum ,anian #b4h -- #b4h #bb4 ,aethiops #c4c -- #c4c #bc4 ,eunostos #b4h -- #b4h #bd4 ,lethes #b4i -- #b4i #be4 ,marsias #c4b -- #c4b #bf4 ,hyblaeus #c4j -- #c4j #bg4 ,amenthes #c4b #c4e #c4c #bh4 ,thoth #b4h #b4c #b4e #bi4 ,nepenthes #b4h #b4c #b4e #cj4 ,triton #b4g 99#b4c #b4e #ca4 ,pyramus #b4i 99#b4j #b4e #cb4 ,astaboras ,s4 #c4b #c4a #c4a #cc4 ,tithonius #b4f #b4b #b4d #cd4 ,vexillum #c4e #b4i #c4b #ce4 ,tartarus -- #b4g #b4g 99 ,poor4 ,here we have widths ranging from eleven degrees to two4 ,the widths given are those when the canal was at or sufficiently near its full strength1 and are measured from the centres of the constituents4 ,we notice two points3 the agreement of the same canal with itself and its systematic disagreement with others4 ,but what is especially to the point1 if we compare the values found at successive oppositions1 we find that for different canals the values agree in their difference4 ,this shows that each of these values is1 in most cases if not in all1 a norm for that particular canal2 a value distinctive of it and to which it either absolutely or relatively conforms4 ,in other words1 the width of the gemination is a personal peculiarity of the particular canal1 as much an idiosyncrasy of it as its position on the planet4 ,two general classes may be distinguished2 those up to about five degrees in width apart and those above this figure4 ,whether such very widely separated lines as go to make up the second class1 such as the ,nilokeras ,i and ,,ii1 constitutes a double is a debatable point4 ,schiaparelli thought they did1 and so classed them4 ,to me it did not at first occur so to consider them1 and in some instances1 such as the ,helicon ,i and ,,ii1 later observations seem to justify the omission4 ,with the ,nilokeras ,i and ,,ii the outcome seems the other way4 ,the reasons for distrust of a physical relation between the constituents is not so much the distance separating them1 nor any lack of parallelism1 as the self-sufficient manner in which they show alone4 ,even this1 however1 tends to be recognized in the narrower pairs as they come to be better seen4 ,it may be that width alone is wholly competent to selective showing4 ,for the farther apart two lines are on the planet1 the more opportunity is afforded the air waves to disclose the one without the other1 a relative revelation which is constantly happening to detail in different parts of the disk4 ,as long as any doubt exists of a physical community of interest1 it seems best to distinguish such possibly merely parallel canals by suffixed numerals4 ,of this class of doubles is the ,nilokeras ,i and ,,ii4 ,so wide is it that ,mr4 ,lampland succeeded in photographing it as such1 the two constituents showing well separated1 and if it prove a true double it will be the first ,martian double to leave its impress on a sensitive plate4 ,although separated by four hundred miles of territory1 the two lines are parallel so far as observation can detect1 which1 of course1 is not so very easy with the lines so far apart4 ,in the country between one crosswise canal certainly lies1 the ,phryxus1 and much shading thus far unaccounted for4 ,recent discoveries1 however1 point to the cause of such shading as lines imperfectly seen4 ,for in some cases the lines have actually disclosed themselves1 and warrant us in believing that it is only imperfect seeing that keeps the others hid4 ,of the pair the ,nilokeras ,i is itself double1 curiously reproducing what sometimes is seen in the case of double stars1 one of whose components turns out to be itself a binary4 ,the second line of the ,nilokeras ,i lies close to its primary on the north1 and was on the only occasion of its detection the merest of gossamers1 while the ,nilokeras ,i itself stood out strong and dark4 ,thus do these ,martian details increase and multiply in intricacy the better the seeing brings them out4 ,in the case of the other doubles1 the doubles proper so to speak1 there is every indication of a physical bond between the pair4 ,what that bond may be is another matter and seems to be of different divulging1 according to the particular instance4 ,at one end of the subject1 both as the widest of these doubles and one of the most important1 stands the ,ganges4 ,the components of the canal are #e4a apart4 ,this great width1 joined to the fact of scant extension1 gives the canal a stocky aspect1 its breadth being but one sixth of its length4 ,its width draws attention to it while the phenomena it exhibits intrigue curiosity4 ,as early as the first opposition of my observations in #ahid1 the canal1 as it underwent the process of doubling1 showed phases of peculiarity4 ,it was first caught by me as a double over toward the terminator1 or fading edge of the disk2 then as it was brought nearer the centre by the gaining upon the longitudes1 showed as a broad swath of shading of a width apparently equal to any it later exhibited4 ,in this appearance it continued for some months1 and then in ,october began to show a clarification toward the centre4 ,once started1 the lightening of its midway advanced till at last1 on ,november #ac1 it stood out an unmistakable double1 the two lines standing where the edges of the swath had previously been4 ,had the observations here been all that one could wish1 the method of gemination would have been certain and of great interest4 ,unfortunately1 the observations left much to be desired1 and those repeated in #ahif-ahig and #aija were of like doubtfulness4 ,a period of swarthy confusion preceded the plainly dual state1 but whether the double simply clarified or widened as well it was not possible to assure one's self4 ,that the canal exhibited plainly the effects of seasonal development was as unmistakable as the steps themselves were open to ambiguity4 ,in #aijc the canal was at its minimum and hardly to be made out4 ,it seemed then to show an actual change in width coincident with alteration of visibility4 ,but this1 too1 could not be predicated with certainty4 ,it was also surmisable that the westernmost line was the one from which the development proceeded4 ,in #aije much more was made out about it1 training in the subject and increased proximity of the planet contributing to the result4 ,it now became clear to me that the canal did develop from the western side2 for the western edge made a dark line of definite boundary from which shading proceeded to the eastern side1 where it faded almost imperceptibly off with no defined line to mark its limit4 ,that this shading gradually darkened was evident1 but that when it could be seen at all it extended to the extreme limit of the eventual double1 restricted the character if not the fact of an actual widening4 ,at this opposition1 too1 the canal passed through its period of minimum visibility and was then seen1 whenever it could be caught1 as a confused swath of full width4 ,in the case of this canal1 then1 a widening in the sense of a bodily separation of two lines seems inadmissible4 ,on the other hand1 the gradual darkening of the swath1 and especially the advance of the darkening from the western side1 points to an interesting process there taking place4 ,illustration3 ,peculiar development of the ,ganges4 ,at the opposite end of the series stands the ,djihoun4 ,as the ,ganges is the widest of the instantly impressive doubles1 so the ,djihoun is the narrowest the eye has so far been able to make out4 ,only two fifths of the width of the ,ganges pair1 this slender double is very nearly at the limit of resolvability4 ,so well proportioned are its lines to the space between them1 however1 that in ease of recognition it surpasses many wider pairs4 ,in form1 too1 it is distinctive1 turning by a graceful curve the trend of the ,margaritifer ,sinus into the ,lucus ,ismenius4 ,with its fundamental branch--the northern of the two--it joins what is evidently the main line of the ,protonilus--also the northern one--to the ,margaritifer ,sinus's tip4 ,illustration3 ,djihoun1 the narrowest double4 ,it differs from the ,ganges in some other important particulars besides width4 ,in its case no band of shading distinguishes it at any time4 ,it has always been two lines whenever it has been seen other than as a single penciling2 the only confusion about it being evidently our own atmosphere's affair4 ,these two lines1 furthermore1 have showed1 within the errors of observation1 always the same distance apart4 ,so that not only no change of intercommunication between the lines but no change in their places apparently occurs4 ,between these extremes in width1 two hundred miles more or less for the ,ganges and seventy-five miles for the ,djihoun1 the distance parting the pairs of most of the double canals lies4 ,from #c to #c4b on the planet may be taken as that of the average2 the degrees denoting latitudinal ones on the surface of ,mars1 the length of which is equal to thirty-seven of our ,english statute miles4 ,most of the canals conform apparently to the type of the ,djihoun rather than to that of the ,ganges4 ,careful consideration of them fails to find any increase or decrease of distance1 between the pairs of the same canal at different times1 which cannot be referred to errors inevitable to observation of such minute detail4 ,in short1 the double is made by the addition of a second line in a particular position and not by a growth out to it of a line coincident to begin with with the first4 ,i have said that the average width between the two lines of the doubles was about #c4 ,it must not be supposed that this average width denotes anything more than an average2 or1 in other words1 that it denotes anything in the nature of a norm4 ,the remark is important in view of a suggestion which ,i have heard made that we have here a system based on fundamental ,martian units1 in which1 or in multiples of which1 the dimensions of the canals are implicitly expressed4 ,such1 however1 does not seem to be the case4 ,in some instances1 indeed1 we have certain evidence to the contrary and that the width of the double is conditioned solely by antecedent place4 ,the ,phison and ,euphrates offer a case in point4 ,these two important arteries in duplicate leave1 as we saw1 from two carets in the ,mare ,icarium1 the ,portus ,sigaei1 held in common tenancy by both4 ,each pair then proceeds down the disk inclined at its own particular angle to the meridian in order to reach by a great circle course a certain spot2 the ,pseboas ,lucus in one case1 the ,luci ,ismenii in the other4 ,as one of these angles is thirty-five degrees while the other is only three1 they must1 from the circumstances of their setting out1 have not only different widths1 but widths determinately different in advance1 since each is1 roughly speaking1 foreshortened by the degree of divergence from the meridian4 ,the one1 therefore1 must be about four degrees to the other's something less than three and a half4 ,this is what they actually are as determined by measurement from observation4 ,that the calculated value agrees with that found from observation helps certify to a community of starting-points1 but it completely does away with comprehensive design in the question of their widths4 ,for if the one were so settled1 the other could not be4 ,indeed1 the next example seems to deny it to both4 ,this example occurs1 too1 not far away from the scene of the first1 in the twin bays of the ,sabaeus ,sinus1 from which depart1 mutatis mutandis1 the double ,hiddekel and the two ,gihon4 ,these twin gulfs bear so little imprint of being other than natural formations1 that they have been universally and very likely quite rightly taken for such ever since ,dawes discovered them in #ahei1 long before things like canals were dreamed of4 ,it is strange that when the ,hiddekel and the ,gihon were found by me to be double in #ahig1 with a branch of both leading from each bay1 the connection between the sceptically scouted doubles and the thoroughly believed-in bays should have been apparent4 ,for to link a ghost to materiality1 if it does not discredit the materiality1 serves to substantialize the ghost4 ,furthermore1 it shows that in this case neither the one double nor the other can have had its width engineered on any preconceived scale1 unless the twin bays be themselves so accounted for4 ,so that it seems useless to seek for cryptic standards in the canals or to think to find them a measure of value from the fact of their being a medium of exchange4 ,illustration3 ,the ,sabaeus ,sinus1 embouchure for the double ,hiddekel and ,gihon4 ,a third instance of the same thing in the case of the ,ganges and the ,jamuna was proved at the last opposition after having long been suspected without my being able to make sure of it4 ,these instances1 taken in connection with the wide range of values in the widths presented by different canals1 serve to show that the distance between the twin lines is an individual characteristic of the particular canal1 and further to point to its cause1 in some cases certainly and possibly in all1 as topographical4 ,the duplicate line makes a convenience of a neighbor1 and suits its distance from its fellow to friendly feasibility4 ,to cut a #8canal' to conform to the country seems logical if not obligatory1 and quite in keeping with the nomenclature of the subject2 but here the starting-point appears to be the only thing considered--the canal once safely launched being left to shift1 or rather not shift1 for itself4 ,,iv ,topography thus introduced to our notice for its effect on the breadth of the doubles proves upon inspection to be of extended application to the whole subject4 ,examined for position these canals turn out to have something to say for themselves bearing on the question of their origin and office4 ,with regard to position1 probably the first query to suggest itself to an investigator to ask is of the direction in which they run4 ,is there a preponderance manifest in them for one direction over another8 ,do they show an inclination to the vertical1 to the horizontal1 or to some tilt between8 ,to answer this we may box the compass1 and taking the four cardinal points with the twelve next most important points between for sectional division segregate the doubles according to their individual trend4 ,as we have no means of determining in which sense any direction is to be taken1--if indeed it is not to be taken alternately in each1--we get eight compartments into one or the other of which all the doubles must fall4 ,this they do in the following manner3-- ,s4 ,n41 ,laestrygon1 ,fretum ,anian1 ,aethiops1 ,amenthes1 ,titan1 ,dis1 ,is #g ,s4 ,s4 ,e4 ,n4 ,n4 ,w41 ,gihon1 ,ganges1 ,tithonius1 ,euphrates1 ,adamas #e ,s4 ,e4 ,n4 ,w41 ,eunostos1 ,triton1 ,tartarus1 ,naarmalcha #d ,e4 ,s4 ,e4 ,w4 ,n4 ,w41 ,astaboras1 ,typhon1 ,pierius #c ,e4 ,w41 ,nar1 ,protonilus1 99,propontis1 ,nectar1 ,cocytus1 ,chaos #f ,e4 ,n4 ,e4 ,w4 ,s4 ,w4 ,deuteronilus1 ,callirrhoe1 ,cerberus ,n41 ,cerberus ,s41 ,sitacus1 ,erebus #f ,n4 ,e4 ,s4 ,w41 ,djihoun1 99,nilokeras ,i ,,ii1 ,avernus1 ,nepenthes1 ,gigas1 ,alander1 ,polyphemus1 ,gelbes1 ,marsias1 ,pyramus1 ,nilokeras ,i1 ,asopus #ab ,n4 ,n4 ,e4 ,s4 ,s4 ,w41 ,jamuna1 ,phison1 ,hyblaeus1 ,cyclops1 ,lethes1 ,thoth1 ,vexillum1 ,hiddekel #h -- #ea 99 ,wide canals4 ,northern hemisphere exclusively4 ,southern hemisphere exclusively4 ,no conclusively marked preponderance for one direction over another manifests itself by this partitionment4 ,nevertheless1 a certain trend to the east of north1 as against the west of north1 is discernible4 ,more than twice as many doubles run northeast and southwest or within forty-five degrees of this as do similarly northwest and southeast1 there being twelve of the latter and twenty-six of the former4 ,that this seems to mean something the nearly equal pairing of quadrantal points goes to show4 ,thus3-- ,n4 ,s4 and ,e4 ,w4 inclined canals number #g #f #ac ,n4 ,n4 ,e4 ,s4 ,s4 ,w4 and ,e4 ,s4 ,e4 ,w4 ,n4 ,w4 inclined canals number #h #c #aa ,n4 ,e4 ,s4 ,w4 and ,s4 ,e4 ,n4 ,w4 inclined canals number #ab #d #af ,e4 ,n4 ,e4 ,w4 ,s4 ,w4 and ,n4 ,n4 ,w4 ,s4 ,s4 ,e4 inclined canals number #f #e #aa -- -- -- #cc #ah #ea a fairly equable division in direction4 ,a trend to the westward would be given a particle descending from the north to the equator by the planet's rotation1 thus turning it southwesterly2 and one to the west to a particle travelling equatorwards from the south1 turning it northwesterly4 ,as the doubles lie in the northern hemisphere1 either in whole or part1 to the extent of #ic1 this might account for the preponderating tilt to the east of north and west of south exhibited by them4 ,it would correspond with the lines of flow4 ,to see whether this be so we will take only those double canals that lie exclusively in the northern and southern hemispheres respectively1 and note those in the former that trend to the west of south as against those that run to the east of it1 and vice versa in the southern4 ,in the northern the proportion of the westerly to the easterly ones is #ag to #d2 in the southern1 #a to #j the other way4 ,of those whose course is common to both hemispheres we find for the ratio of the southwesterly to the southeasterly #h to #g4 ,but the proportion of the course of these canals in the two hemispheres is on the side of this same ratio4 ,from their direction we now pass to consideration of their distribution in longitude4 ,it appears that some meridians are more favored than others4 ,the hemisphere which has the ,syrtis ,major for centre is more prolific in them than its antipodes4 ,from longitude #hj to #bjj there are ten doubles1 from #bjj to #cbj twenty-four1 and from #cbj to #hj seventeen2 or1 roughly1 in the proportion of #b1 #e1 and #c4 ,that this distribution means anything by itself is doubtful2 it is much more likely to be a general topographical consequence of their distribution in another direction1 which proves to be highly significant and which we shall now expose--that of latitude4 ,if we separate the surface into zones1 each ten degrees wide1 and count the doubles found traversing in whole or part the several zones1 we find the following arrangement3-- ,column ,headings3 ,a ,at ,opposition of #aijc ,alone ,b ,at ,all ,oppositions so far observed at ,flagstaff ,double ,canals of ,mars arranged according to ,latitude ,a ,b ---------------------------------------- ----------------------------- ,between #cj ,s4 and #bj ,s4 ,tithonius1 ,nectar1 ,laestrygon #b #c ,between #bj ,s4 and #aj ,s4 ,jamuna1 ,ganges1 ,gigas1 ,laestrygon1 ,cyclops1 ,titan1 ,tartarus1 ,polyphemus1 ,tithonius #g #i ,between #aj ,s4 and #j ,jamuna1 ,ganges1 ,gigas1 ,laestrygon1 ,cyclops1 ,cerberus ,s1 ,aethiops1 ,lethes1 ,amenthes1 ,triton1 ,phison1 ,euphrates1 ,titan1 ,tartarus1 ,adamas1 ,typhon1 ,vexillum1 ,asopus1 ,naarmalcha1 ,polyphemus #ae #bj ,between #j and #aj ,n4 ,gihon1 ,djihoun1 ,jamuna1 ,ganges1 ,gigas1 ,laestrygon1 ,cerberus ,n1 ,cyclops1 ,cerberus ,s1 ,eunostos1 ,aethiops1 ,lethes1 ,amenthes1 ,triton1 ,nepenthes1 ,phison1 ,euphrates1 ,sitacus1 ,hiddekel1 ,tartarus1 ,adamas1 ,asopus1 ,typhon1 ,vexillum1 ,cocytus1 ,is1 ,avernus ,n1 ,naarmalcha1 ,polyphemus #ba #bi ,between #aj ,n4 and #bj ,n4 ,gihon1 ,djihoun1 ,jamuna1 ,nilokeras ,i and ,,ii#d1 ,nilokeras ,i1 ,ganges1 ,gigas1 ,eunostos1 ,aethiops1 ,lethes1 ,amenthes1 ,thoth1 ,astaboras1 ,phison1 ,sitacus1 ,euphrates1 ,hiddekel1 ,adamas1 ,asopus1 ,gelbes1 ,avernus ,n1 ,erebus1 ,naarmalcha1 ,vexillum1 ,is1 ,dis #ah #bf ,between #bj ,n4 and #cj ,n4 ,gihon1 ,djihoun1 ,jamuna1 ,nilokeras ,i ,,ii1#d ,nilokeras ,i1 ,alander1 ,hyblaeus1 ,lethes1 ,amenthes1 ,thoth1 ,sitacus1 ,astaboras1 ,vexillum1 ,phison1 ,euphrates1 ,hiddekel1 ,adamas1 ,eunostos1 ,aethiops1 ,gelbes1 ,avernus ,n1 ,naarmalcha1 ,is #ag #bc ,between #cj ,n4 and #dj ,n4 ,deuteronilus1 ,alander1 ,nar1 ,marsias1 ,fretum ,anian1 ,amenthes1 ,thoth1 ,vexillum1 ,phison1 ,euphrates1 ,hiddekel1 ,adamas1 ,eunostos1 ,djihoun1 ,gihon1 ,nilokeras ,i1 ,chaos1 ,gelbes1 ,aethiops1 ,naarmalcha #ab #bj ,between #dj ,n4 and #ej ,n4 ,fretum ,anian1 ,pyramus1 ,protonilus1 ,propontis#d #c #d ,between #ej ,n4 and #fj ,n4 ,callirrhoe1 ,fretum ,anian1 #c #c ,pierius ,between #fj ,n4 and #fc ,n4 ,pierius1 ,callirrhoe #b #b ,from this tabulating of them it is apparent that the doubles are practically confined to the zones within forty degrees of the equator4 ,only #g of them straggle farther north than this1 while above #fc north latitude and #ce south latitude there are none4 ,such a distribution is not in proportion to the areas of the zones1 which though diminishing toward the poles do so at no such rate4 ,the surface included between the equator and #dj of latitude is #fe of the hemisphere1 whereas the fraction of the number of doubles found there is #ic4 ,the doubles are1 then1 an equatorial feature of the planet1 confined to the tropic and temperate belts4 ,to perceive the tropical character of the doubles in another way we have but to consider the zonal distribution of the single canals4 ,unlike the former the latter do not thin out as one advances toward the poles2 since in the arctic regions single canals bemesh the surface as meticulously as elsewhere4 ,it is only that they there replace the doubles2 or1 not to put the cart before the horse1 it is the doubles that in part replace the singles in the tropics4 ,and that this arrangement has something physical behind it by way of cause is curiously shown by two canals1 the ,arnon and the ,kison1 which are neither of the one kind nor yet the other1 but a cross between the two4 ,for the ,arnon and the ,kison are convergent doubles2 the two lines of the ,kison leaving a common point at the edge of the polar cap and separating as they travel south1 while the two ,arnon take up and continue the divergence1 connecting at last with the parallel pair of the ,euphrates4 ,these canals thus make transition between the true doubles and the true singles1 and may be looked upon as endowed with the potentialities of both4 ,from their association with the double ,euphrates1 it is clear that the transition between the two forms is not only formal but physical1 and that the stopping of the dual condition at the fortieth parallel is not the outcome of chance4 ,it may occur to the thoughtful that the doubles appear confined to the more tropical portions of the planet because of a better presentation of those zones1 the reader supposing the planet to be seen axised perpendicularly to the plane of sight1 as geographies represent the earth's globe4 ,the supposition1 however1 is erroneous4 ,we sometimes see the planet so1 but more often not4 ,such is the tilt of the ,martian axis to the plane of the ,martian ecliptic that the different zones are rarely seen on an even keel1 so to speak1 their aspects shifting totally from one opposition to another4 ,what shows in mid-disk on one occasion may be forty-eight degrees removed from it at another1 a distance amounting to three-quarters of the way from apparent equator to apparent pole4 ,thus the double canals are for some intrinsic reason equatorial features of the planet as opposed to polar ones4 ,and this not simply because of greater space there4 ,duality is a result of conditions intrinsic to the several localities4 ,what the cause may be is related to the character of the things themselves1 which we shall later consider4 ,for the moment we may note that the fact disposes quietly of the diplopic theory of their manufacture4 ,for1 for diplopic doubles to show such respect for the equator would betoken a courtesy in them to be commended of ,sydney ,smith4 ,but this is not their only geographic bias4 ,in addition to not being partial to the poles1 the double canals show a certain exclusiveness toward the dark areas generally4 ,not only do they avoid the arctic and antarctic zones entirely1 but they largely shun the blue-green regions4 ,in these but two suspicions of doubles occur1 in the ,aonium ,sinus1 although single canals there are as numerous as anywhere else on the planet4 ,nevertheless1 although they avoid running through them1 they run from them in a manner that is marked4 ,proceeding from the great diaphragm are no less than #bh out of the #ec doubles4 ,connecting directly with these are #ag more2 while the remaining #h are also associated through the intermediarism of dark areas1 the ,solis ,lacus and the ,trivium4 ,in like relation to dark regions1 they are limited on the north by the ,mare ,acidalium1 the ,propontis1 the ,wedge of ,casius and their interconnecting bands1 the ,pierius1 ,callirrhoe1 ,helicon4 ,in this manner do they form a broad girdle round the planet's waist1 leaving the polar extremities bare4 ----- ,footnote #d3 ,very wide and possibly not of the same class4 ,,chapter ,,xix ,,canals ,,in ,,the ,,dark ,,regions ,seventeen years after the recognition of the canals in the light regions occurred another important event1 the discovery of a similar set in the dark ones4 ,the detection of these markings in the dark areas was a more difficult feat than the perceiving of those in the light1 and in consequence was later accomplished4 ,also was it one where recognition came by degrees4 ,i have previously pointed out what this discovery did for the seas--nothing less than the taking away of their character in a generally convincing manner4 ,to one who had carefully considered the matter1 the seas had indeed already lost it1 as was shown in ,chapter ,x1 but to those who had not these canals presented a very instant proof of the fact4 ,from such not wholly supererogatory service they went on to furnish unlooked-for help in other directions4 ,their discovery showed in the first place that no part of the planet's surface was free from canal triangulation4 ,but it did more than this4 ,for these canals in the dark regions left the edge of the #8continents' at the very points where the canals of the light regions entered them1 which fact proved for them a community of interest with the latter4 ,such continuation was highly significant1 since it linked the two together into a single system1 compassing the whole surface of the planet4 ,starting from the places where the light-region canals come out upon the great girdle of seas that stretches all round the planet1 most of the new canals headed toward the passes between the islands south1 as nearly polewards as circumstances of local topography would permit4 ,in the broader expanses of the ,syrtis ,major and the ,mare ,erythraeum1 besides main arteries others went to spots in their midst after the same fashion as those of the light regions4 ,these spots differed in no way apparently from their fellow oases elsewhere4 ,from a spot in the centre of the ,syrtis three great lines thus traveled south3 the ,dosaron1 heading straight up the ,syrtis on the meridian till it struck the northernmost point of ,hellas2 the ,orosines1 inclined more to the right1 passing through the dark channel to the west of that land and so proceeding south2 and lastly the ,erymanthus turning eastward till it brought up finally at the ,hesperidum ,lucus4 ,where1 on the other hand1 the long chain of lighter land1 called by ,schiaparelli islands1 and stretching from the ,solis ,lacus region westward to ,hellas1 offered only here and there an exit1 the canals made for these exits4 ,the canals in the ,mare ,sirenum1 the ,mare ,cimmerium1 and the ,mare ,tyrrhenum struck more or less diagonally across those seas from their northern termini to the entrances of the straits between the islands1 thus lacing the seas in the way a sail is rolled to its spar4 ,from the exact manner in which they connected with the light-region canals they proved the two to be part and parcel of one system1 which in its extension was planet-wide and therefore proportionately important4 ,whatever of strange interest the curious characteristics of the canals themselves suggested was now greatly increased by this addition2 for the solidarity of the phenomenon affected the cogency of any argument derived from it4 ,in #ahid only the dark areas of the southern hemisphere were found to be thus laced with lines4 ,for then so great was the tilt of the planet's south pole toward the earth1 that while those zones were well displayed the dark patches of the northern hemisphere were more or less hull-down over the disk's northern horizon4 ,contrast was the open sesame to their detection4 ,when the maria show dark1 the lines are lost in the sombreness of the background4 ,as the maria lighten the lines come out4 ,such was amply witnessed by the effect in #ahid and #ahif4 ,in #ahid ,i found it impossible to perceive them1 except where the ,padargus crossed ,atlantis1 for the hue of the maria themselves was then very dark4 ,in #ahif1 on the other hand1 ,i saw them without difficulty4 ,what is also of interest3 so soon as seen they appeared small1 without haziness or distention4 ,as the oppositions succeeded one another the northern regions rose into view1 and with their appearance came the detection in them of the same phenomena4 ,no large dark areas like the diaphragm exist there1 but the smaller patches of blue-green which bestrew them proved to be similarly meshed4 ,at first canals were evident upon their peripheries1 contouring them about2 then the bodies themselves of the patches showed grid-ironed by lines4 ,the ,mare ,acidalium with its adjuncts1 the ,lucus ,niliacus on the south and the ,lacus ,hyperboreus on the north1 thus stood out in #aija4 ,on a particularly good evening of definition at the end of ,may1 the ,mare suddenly made background for a sunburst of dark rays1 six of them in all radiating from a point between it and the ,lacus ,hyperboreus4 ,considering how sombre the ,mare was at the time1 this was as remarkable a vision as it was striking to see4 ,although at the moment the sight was of the nature of a revelation1 these lines have been amply verified since1 as the ,martian season has proved more propitious4 ,similar decipherment has befallen all the other patches of blue-green in the northern hemisphere2 these having shown themselves first circumscribed and then traversed by canals4 ,interesting instances were the ,wedge of ,casius and the ,propontis4 ,these markings1 first perceived years ago as mere patches of shading1 then partially resolved by ,schiaparelli1 now stood revealed as a perfect network of lines and spots4 ,so many of both kinds of their detail occupied the ground that to identify them all was matter of exceeding difficulty4 ,the outcome is shown in the diagrammatic representations opposite and on page #bef4 ,these drawings disclose better than any description the mass of detail of which the patches are in reality composed1 and serve to convey an idea of the complexity involved4 ,if the general canal system seems intricate1 here is something which exceeds that as much again4 ,illustration3 ,the ,propontis1 #aije4 ,the extension in this manner of the curious triangulation of the light areas into and through all the dark areas as well1 by thus spreading the field of its operations over both terranes complexioned so unlike1 greatly increases the cogency of the deduction that this detail is of later origin than the background upon which it rests4 ,that the mesh of lines covers not only the ochre stretches of the disk1 but the blue-green parts as well1 makes it still more certain that it is not a simple physical outcome of the fundamental forces that featured the planet's face4 ,for in that case it could not with such absolute impartiality involve both alike4 ,thus here1 again1 we find corroboration by later observations of what earlier ones established4 ,a last link in the chain of canal sequences remains to be recorded4 ,just as the lines in the dark regions continued those in the light1 so they themselves turned out to be similarly prolonged and in no less suggestive a manner4 ,for when the north polar zone came to be displayed1 canals were evident there1 continuing those in the other zones and running at their northern ends into dark spots at the edge of the polar cap4 ,here1 then1 we have the end of the whole system1 or more properly its origin1 in the polar snows4 ,the significance of this will be seen from other phenomena1 to a consideration of which we now proceed4 ,,chapter ,,xx ,,oases ,next to be caught of the details of this most curious network that meshes the surface of ,mars was a set of phenomena stranger even than the lines2 to wit1 dark round dots standing at their intersections4 ,more difficult to make out than the lines1 they were in consequence detected thus later by fifteen years4 ,once discovered1 however1 it became possible to trace their unconscious recognition back in time4 ,thus ,schiaparelli told the writer in #ahie1 apropos of those found at ,flagstaff1 that he had himself suspected them but could not make sure4 ,some of them stand figured in his ,memoria ,sesta dealing with the opposition of #ahhh1 but not published till #ahii4 ,in such posthumous recognition1 as one may call it1 the spots repeated the history of the canals4 ,for ,schiaparelli had himself pointed out a similar preconscious visioning of the canals in the delicate pencilings of ,dawes and the streaks of ,lockyer1 ,kaiser1 and ,secchi1 now translatable as representing the ,phison1 the ,euphrates1 and half a dozen other canals imperfectly seen4 ,that both the canals and the oases were thus sketched before they were seen well enough to be definitely discovered is to an unprejudiced mind among their strongest credentials to credit4 ,nor was ,schiaparelli the sole person thus to get proof before letter4 ,one of their very earliest portrayals appears in a drawing by ,otto ,boeddicker1 made on ,december #bf1 #ahha1 where the ,pseboas ,lucus is clearly represented4 ,in a still more imperfect manner some of the spots had been adumbrated and their shadows drawn long before that4 ,thus they may be deciphered as the cause of patches drawn by ,dawes in #ahfd1 though none of them were in any definite sense detected till #ahgi1 and only then so ill defined that their true character was not apparent4 ,as patches they are still commonly seen at observatories where the observational conditions are not of the best and the study of the planet not systematically enough pursued to have them disclose their true shape and size4 ,the history of their detection is resumed in the experience of the individual observer4 ,during the course of my own observations ,i have had occasion to notice the several stages in recognition of the spots which have marked their chronologic career4 ,as with the lines1 three stages in the appearance of the spots may be remarked3 first1 where the scattering of the rays is so wide that dilution prevents anything from being seen2 second1 where the commotion being less the object appears as a gray patch2 and third1 where in comparative quiet it condenses into a black dot4 ,for the two former our own air waves are to blame4 ,in coursing waves of condensation and rarefaction they spread the image of the spot as they do that of the canal4 ,then as the currents calm the spot shrinks to its normal proportions1 and in so doing darkens in consequence of being less widely diffused4 ,thus the evolution in perception which may take place in the course of an hour for a particular observer represents exactly what has occurred in the person of the race by the improvement in observational methods and sites4 ,that the spots1 although wider than the canals1 remained longer hidden from human sight1 is due to the optico-physic fact that a tenuous line may be perceived owing to its length when a dot of the same diameter would be invisible4 ,summation of impressions is undoubtedly the cause of this4 ,the mere fact that a row of retinal cones is struck1 although each be but feebly affected1 is sufficient to raise the sum total into the sphere of consciousness4 ,in the second stage of their visibility1 the spots are in danger of mistake with the smaller true patches of sombre hue which fleck the northern hemisphere of the planet and from which they differ totally in kind1 totally so far as our present perception goes4 ,such true patches consist of a groundwork of shading1 upon which1 indeed1 are superposed the usual network of lines and spots4 ,prominent as instances of them are the ,trivium ,charontis1 the ,wedge of ,casius1 and the ,mare ,acidalium4 ,with patches of the sort the spots proper must not be confounded4 ,close treading on the heels of the detection of lines athwart the seas came the recognition of spots there likewise4 ,at the opposition of #ahif-ahig the number was added to2 and so the tale has been steadily increased4 ,their number as found at ,flagstaff up to the present time1 that is1 to the close of the opposition of #aije1 is #ahf2 of which #aba lie in the light regions1 #db in the dark areas of the southern hemisphere1 and #bc in the smaller sombre patches of the northern zones4 ,from their relationships and behavior it became apparent that the spots were not lakes but something which answered much more nearly to oases4 ,of the spots three kinds may be distinguished3 the large1 the little1 and the less1 if by the latter term it may be permitted to denote what has but collateral claim to be included and yet demands a certain recognition4 ,for though not spots like the others1 the members of the third class have certain traits in common with them while differing radically in others4 ,to the kind called large belong the greater number of spots so far found upon the disk4 ,they are large only by comparison with the little4 ,for they measure according to my latest determinations but seventy-five or one hundred miles in diameter2 on the planet some two degrees across4 ,sizable black pin-heads1 it is their tone that chiefly catches the eye1 for they are commonly the darkest markings on the disk4 ,against the ochre stretches they appear black1 and even in the midst of the dark areas they stand out almost as much contrasted with their surroundings as these do with the light regions themselves4 ,about a hundred and forty are now known4 ,those in the light areas were discovered first2 those in the dark regions being harder to see4 ,of this first kind are such spots as the ,pseboas ,lucus1 the ,aquae ,calidae1 the ,lacus ,phoenicis1 and the ,novem ,viae2 or1 in ,english1 the ,grove of ,pseboas1 the ,hot ,springs1 the ,phnix ,lake1 and the ,nine ,ways1 to mention no more4 ,that they bear dissimilar names implies no dissimilarity in structure4 ,the phenomena are all remarkably alike1 and clearly betoken one and the same class of objects2 differing between themselves at most in size and importance4 ,in form they all seem to be round4 ,they certainly appear so1 and were it not that retinal images of small areas tend to assume this shape might implicitly be credited with being what they seem4 ,the reason for optical circularity probably resides in the shape of the retinal cones and in their patterning into a mosaic floor4 ,so that unless a sufficient number of cones be struck the image takes on to consciousness a roughly circular figure--whether it be so in fact or not4 ,in the present case1 however1 they seem to be too well seen for self-deception of the sort4 ,the little are distinguished from the large by being pin-points instead of pin-heads4 ,they are most minute2 from fifteen to twenty-five miles in diameter only4 ,that anything except size distinguishes the two apart is from their look improbable4 ,in color or rather tone1--for distinctive color is of such minute objects unpredicable1--they would seem to be alike4 ,such is also the case with their distribution and detail association4 ,illustration3 ,fons ,immortalis1 ,june #ai4 ,to the second class belong the ,fons ,juventae1--,schiaparelli's ,fountain of ,youth1--the ,fons ,immortalis in ,elysium in #aije1 and the ,gygaea ,palus1 besides many more4 ,these are all pin-points1 just upon the limit of vision1 and noteworthy chiefly for being visible at all4 ,all those detected so far lie not very distant from the equator1 which may or may not be a matter of accident4 ,it is not one of perception1 since this part of the planet was not the best place for observation at the time they were discovered4 ,to make out one of these little dots is a peculiarly pleasing bit of observation1 as it requires particularly good definition4 ,one might almost take them for fly-specks upon the image did they not move with the disk4 ,they have no perceptible size and yet are clearly larger in diameter than the canals which run into them2 which proves how very slender the latter must be4 ,very early in the detection of the spots it became evident that they were not scattered haphazard over the surface1 but that on the contrary they were never found except at the meeting-points of the lines4 ,from this it must not be supposed1 as has been done1 that the spots are merely optical reinforcements of the lines at their crossings due to the more crowded character there of the lines themselves4 ,that they are not such is demonstrated by the existence of crossings where1 either temporarily or permanently1 none appear2 which shows that they are far too well seen for any such illusion about them to be possible4 ,at these crossings the lines traverse one another without thickening1 whether they be single or double lines4 ,the spots1 on the other hand1 are much wider than the lines1 giving a beaded look to the threads4 ,in short1 they are the knots to the canal network4 ,all the more important junctions are characterized by their presence4 ,such starred junctions are not confined to the ochre regions2 they dot the light and the dark areas with equal impartiality1 thus showing themselves to be independent of the nature of the ground where large stretches of country are concerned4 ,on the other hand1 they appear to be unusually numerous in the smaller1 isolated1 dark areas of the northern hemisphere1 such as the ,trivium1 the ,mare ,acidalium1 the ,propontis1 and the ,wedge of ,casius4 ,here they crowd2 and one cannot avoid the inference that their plentifulness in these regions is not due to chance4 ,illustration3 ,utopia regio--#aijc4 ,to the large spots1 those of the first class1 fall the places of intersection of the largest and most numerous canals1 while the little spots make termini to fainter lines1 ones that bear to them a like ratio of unimportance4 ,spots and lines are thus connected not simply in position but in size4 ,the one is clearly dependent on the other1 the importance of the centre being gauged by the magnitude of its communications4 ,from the fact of association we now pass to the manner of it1 which is quite as remarkable4 ,the position of the spot relative to its tributary canals depends upon the character of the connecting lines4 ,if the canal be single it runs1 so far as may be judged1 straight into the middle of the oasis1 or1 in other words1 the oasis is symmetrically disposed about its end4 ,this is true of the greater number of the large spots and of all the little ones1 since the latter have as connections only single canals4 ,in the case of a double canal arriving at a spot1 a different and most curious dependence is observable4 ,this fact ,i first noticed in a general way at the opposition of #ahif-ahig1 the initial appearance of it being presented on ,september #cj1 #ahif1 by the ,coloe ,palus and the ,phison4 ,it was again visible in the case of the spots in the ,trivium at the time the canals leading to that place doubled in ,march1 #ahig4 ,but the exact nature of the phenomenon was not fully appreciated till #aijc1 when the thing was seen so well as to appear cut on copper plate4 ,it was this3 the spot is exactly embraced between the two arms of the double canal4 ,it is1 moreover1 seemingly perfectly round and just fits in between the parallel lines4 ,the ,ascraeus ,lucus was the first spot that showed thus in association with the double ,gigas4 ,others followed suit in so showing1 several specimens presenting themselves so well as to leave no doubt of the precise connection4 ,the sight presented by such a spot and its incasing double is a beautiful bit of detail1 perhaps the most beautiful so far to be seen upon the ,martian disk4 ,the distinctness with which it stands out on occasion suggests a steel engraving1 and shows how clear-cut the ,martian features really are when our own air ceases from troubling and allows them to be at rest4 ,incidentally1 we may note that this phenomenon alone serves to disprove the diplopic theory of the production of the double canals4 ,for if a double were a single line seen out of focus1 any spot upon it should be doubled too4 ,illustration3 ,ascraeus ,lucus and ,gigas4--,march4 #b4 #aijc4 ,it may seem to the reader as if what was seen in #aijc was but an unimportant advance over the observed phenomena of #ahif-ahig4 ,not so1 however4 ,for with the earlier instances it was not possible to be sure of the precise limits of the spot with regard to the double4 ,the ,coloe ,palus1 on the one hand1 did not fill all the space apparently between the double ,phison2 while the ,lucus ,ismenius more than did so with the double ,euphrates4 ,to have set down the different appearances to insufficient definition would have been a great mistake1 as subsequent observation has served to show4 ,the ,lucus ,ismenius instances this4 ,in #ahif-ahig it was seen terminating the ,euphrates1 blocking all the space between the two lines and extending a little upon either side of them4 ,now1 from its appearance in #aija it was evident that the effect had been produced by twin spots lying along the ,deuteronilus1 the axis joining them being perpendicular to the ,euphrates4 ,in #aijc the relation was still better explained by what appeared then1 when not only did the two spots stand out1 but the ,euphrates showed with a line running centrally into each4 ,although originally seen by ,schiaparelli as a single spot and so at first seen by me1 better acquaintance with the disk disclosed to both observers its really dual character4 ,as this pair has persisted through all three of the most recent oppositions1 it seems fairly certain that it is always of this character1 and more fitting1 therefore1 to give it the plural appellative4 ,this is the single instance of a double oasis4 ,there are many that lie close together and might be taken as such2 but this is the only one where the connection is intrinsic4 ,according to measures of the drawings of #aije extending through six presentations1 the distance between the twin oases is #d4b4 ,their relation to the canals which run into them is of the most complicated description and of the most suggestive character4 ,for to the twin spots converge no less than seven double canals1 one wedge-shaped pair and three single canals1 a most goodly number of communication lines4 ,four of the double canals run into the oases with one line to each2 these canals are the ,astaboras1 the ,naarmalcha1 the ,euphrates1 and the ,hiddekel4 ,three doubles1 the ,protonilus1 the ,djihoun1 and the ,deuteronilus1 embrace the oases between their two lines1 while1 in the singles1 the canal connects with one or other of the twins1 as the case may be4 ,now1 there is method as to which of the doubles shall straddle1 which embrace1 the two ,ismenii4 ,those which leave the place parallel or nearly so to the direction joining the ,luci1 inclose them both2 those of which the setting forth is at an angle to this direction depart1 each line of the pair1 from the eastern and the western spot respectively4 ,illustration3 ,peculiar association of the ,luci ,ismenii with double canals4 ,consider1 now1 the disposition of these seven pairs of lines4 ,all of them lie in one semicircle about the ,luci1 beginning with the ,protonilus on the east and ending with the ,deuteronilus on the west4 ,furthermore1 all follow approximately arcs of great circles1 except the ,djihoun1 and all send one of their twin lines to one ,lucus1 one to the other4 ,the data are enough to make this statement possible4 ,although the west line of the ,naarmalcha has not been caught entering its oasis1 the east one has been seen to enter the other1 and the width of the double shows that the west one must enter the corresponding spot4 ,in the case of the ,astaboras the double has only been observed as far as the ,vexillum1 but the south line has continued on to the west ,ismenius1 and here again the width makes it certain that were the canal double throughout1 the other line must enter the east ,ismenius4 ,from the base line of the ,proto-,deuteronilus the inclinations of the seven pairs are as follows3-- ,protonilus #j ,due ,east ,astaboras #dj ,north of ,east ,naarmalcha #gj ,north of ,east ,euphrates #hj ,north of ,west ,hiddekel #ee ,north of ,west ,djihoun #j ,north of ,west ,deuteronilus #j ,due ,west ,now1 the width between the two lines of the four canals to the east increases regularly from the ,protonilus round2 the ,protonilus being the narrowest double1 the ,astaboras the next1 the ,naarmalcha the next1 and the ,euphrates the widest4 ,and from the width between the twin oases1 it would seem that they severally enter the centres of them4 ,what takes place in the case of the ,hiddekel1 which is wider than its tilt would imply1 and in the ,djihoun1 which is narrower1 is not so clear4 ,but that they enter the oases in some place is certain4 ,illustration3 ,lucus ,ismenius4 ,march #aijc4 ,the spots make common termini for all the canals of a given neighborhood4 ,in other words1 canals converge to the places occupied by the spots and do not cross haphazard according to the laws of chance4 ,only one instance exists where a spot fails to gather to itself the whole sheaf of canals and even there it collects all but two4 ,this anomaly is the ,pseboas ,lucus4 ,the peculiarity of this oasis is that it lies not on1 but just off1 the ,protonilus4 ,that it does so is exceeding curious1 considering that it is the sole example of such extra-canaline position4 ,strictly speaking1 it is not the ,protonilus but the point where the ,protonilus turns into the ,nilosyrtis to which it stands thus neighboringly aloof4 ,and this may explain the anomaly4 ,for the ,nilosyrtis has not the full geometric regularity of the normal canal1 and seems to have been a more or less fundamental feature of the region4 ,for the rest1 the ,lucus has the form and possesses the canal connections appropriate to its state4 ,it is apparently round1 and lies between the twin lines of the ,phison and also between those of the ,vexillum4 ,not far from the ,pseboas ,lucus are to be found all the examples of the third class of spots2 for so far they have not been observed outside of ,aeria1 a region peculiarly peopled by double canals4 ,with double canals they are necessarily associated1 inasmuch as they consist of shading in the form of a square or parallelogram1 filling the deltas between two pairs that cross4 ,thus have shown the ,coloe ,palus at the crossing of the double ,phison with the double ,astaboras1 and the ,juturna ,fons where the double ,sitacus traverses the double ,euphrates4 ,at these same places a fourth kind is sometimes noticeable3 a four-square set of pin-points or a two-square set of the same at the corners of the line-made parallelogram4 ,this kind may well be synchronous with the third1 though it has only been noticed at consecutive presentations4 ,the third1 however1 has no observed dependence upon the first or second classes4 ,and this serves to make more probable the true objectivity of the circular and the square figures respectively shown by each4 ,the spots apparent in the dark regions do not appreciably differ in either size or shape from the bulk of those visible in the light4 ,equally with them they seem to be round1 small1 and nearly black4 ,they would seem1 too1 in the great diaphragm--or larger contiguous sombre region--to be equally plentifully distributed4 ,,chapter ,,xxi ,,carets ,,on ,,the ,,borders ,,of ,,the ,,great ,,diaphragm ,functionally related to the canal system1 and yet in look and location contrasted with its other details1 is a further set of markings1 detected by me in #ahid1 and reseen at subsequent oppositions since1 along the north border of the southern seas4 ,they lie upon what used to be thought the continental coastline1 the fringing edge of that almost continuous band of shading that belts the ,martian globe throughout the southern subtropic zone and called by ,schiaparelli the great diaphragm4 ,the terrane lends itself to the appellative1 forming1 as it does1 a dark dividing strip of country between the brilliant reddish-ochre hemisphere on the north and the half-toned islands to the south of it4 ,by ,schiaparelli it was thought to be one long ,mediterranean1 and though its marine character is now disproved1 that it lies lower than the bright ochre regions is likely4 ,to this difference of level is probably due the peculiar phenomenon which there manifested itself to careful scrutiny in #ahid4 ,for it was there only that it occurred4 ,the phenomenon in question consisted of nicks in the coastline1 of triangular shape and filled with shading4 ,they occurred at intervals along it and were of the general form of carets1 such marks as one makes in checking items down a list4 ,their position was always where a canal debouched from the diaphragm upon its career across the open continent4 ,the canal itself was by no means necessarily visible4 ,on the contrary1 at first it was usually absent4 ,such was the case with those marking the departure-points of the ,phison and ,euphrates and of the ,amenthes and ,lethes1 which appeared1 without being well defined1 from the moment the planet came to be scanned4 ,one by one these carets stood out to view1 punctuating the points where canals later were to show or terminating those that already existed4 ,strung thus with them at intervals was the whole coastline of the diaphragm1 beginning with the ,mare ,icarium and stretching round through the ,mare ,tyrrhenum1 ,mare ,cimmerium1 ,mare ,sirenum1 and ,mare ,erythraeum to the ,mare ,icarium again4 ,as the planet got nearer to the earth their peculiar shape began to define itself1 and it was again in the case of those giving origin to the ,phison and ,euphrates that the recognition came first4 ,what had appeared earlier simply as a spot now stood out as two triangular notches1 indenting the coast and giving exit at their apices1 the eastern one to the ,phison1 the western to the ,euphrates4 ,these were the things1 then1 that had constituted the ,portus ,sigaeus of ,schiaparelli4 ,commonly the carets lie at the bottom of well-marked bays1 as1 for example1 those terminating the ,syrtis ,minor and the ,sinus ,titanum4 ,but frequently they are placed in the very midst of a long and otherwise unaccented coast1 as is the case in mid-course of the ,mare ,cimmerium and the ,mare ,sirenum4 ,yet in no instance is the thing unassociated with a canal4 ,in every case one or more canals leave the caret for their long traverse down the disk4 ,this is not their only canal connection4 ,when the canals in the dark regions came to be discovered1 each of them was found by me1 as nearly as difficult observations would permit1 to be associated with the caret upon its other side4 ,thus the lacing of the ,mare ,cimmerium and ,sirenum used them as its reeving-points4 ,similarly those at the mouths of the ,phison and ,euphrates did duty likewise to the ,maesolus and the ,ion4 ,in such manner the carets stood in dual relation to canals2 subserving a purpose to the light-region canals on the one hand and to the dark-region ones on the other4 ,in a way the caret1 then1 holds the same position toward the canals that do the spots in the light or dark regions4 ,like them it is a canal-distribution point4 ,unlike them1 however1 in shape it is triangular instead of round1 and we are piqued to inquire to what cause it can owe its different contour4 ,the answer seems to lie in the character of the locality1 not simply in its complexion4 ,for the spots in both the northern and the southern dark patches are as circular as those standing in the light1 whether they lie in the centre or upon the edges of them4 ,the edges of the northern patches1 however1 and the other sides of the southern ones do not present the clear-cut character of the northern coast of the diaphragm4 ,where they seem to be definitely bounded they are so by darker canals4 ,this hints that their contours are not defined by antithesis of level1 while that of the northern coast of the great diaphragm is4 ,difference of altitude is then concerned in their constitution2 the canal system here falls to a lower level1 and these triangular spots instead of round ones are the result4 ,topographic only1 such explanation leads the way to a more teleologic one1 and serves even on first acquaintance to stir curiosity to some satisfying cause4 ,suggestive in several ways for its resemblance to the carets is another detail not far distant from the ,portus ,sigaei1 the twin-forked ,sabaeus ,sinus4 ,curiously enough1 this feature of ,mars1 which has been well known and recognized ever since the eagle-eyed ,dawes detected it more than forty years ago1 proves to be a sort of connecting link between the main markings and the details of more modern detection4 ,the twin-forked ,sabaeus ,sinus1 as its name implies1 is of the form of a double bay2 was considered to be one in fact so long as the maria were held to be seas4 ,it straddles the point of land which1 called the ,fastigium ,aryn1 has been taken for the ,greenwich of ,martian longitudes4 ,each #8bay'--not in truth a bay at all--indents the ochre in an acute triangle1 from the tip of which many canals proceed like the rays of a fan from a holding hand4 ,both tips are darker than the main body of the dark mare from which they proceed4 ,they thus recall in general character the carets4 ,they further reproduce specifically the ,portus ,sigaei1 for they give origin to two doubles1 the ,gihon and the ,hiddekel1 in exactly the same manner that the two nicks of the ,portus ,sigaei do to the ,phison and ,euphrates4 ,nor are their tips much farther apart than those of the ,portus1 five degrees measuring the spread of the one and four degrees that of the other respectively2 the reason for their earlier discovery lying in their greater size4 ,they thus perform the same office as the ,portus ,sigaeus1 are quite comparable to it in width1 and differ in shape only as a larger and more acute triangle differs from a smaller and blunter one4 ,undreamt of by ,dawes and unheeded since1 they were the first hint to the world of the duality which forms so strangely pervasive a feature of the canal system of the planet4 ,thus the carets stand connected with the canals quite as intimately as the oases but in a significantly different manner4 ,for1 in addition to their intermediary standing between the light regions and the dark1 their relation to the doubles is peculiar4 ,an instance is offered by the double ,euphrates and another by the ,ganges4 ,the ,euphrates1 as we saw in ,chapter ,,xviii1 leaves the ,portus ,sigaei at the south1 one line leaving each caret centrally1 so that each caret is concerned only with its own line and has no connection with its fellow4 ,at their northern ends both lines have similarly each its own ,lucus ,ismenius4 ,the like seems to be true of the ,ganges4 ,similarly the twin ,titan1 have each its own4 ,such twin duty in the matter of doubles seems to be the rule with the carets1 even more so than with the oases2 and this is probably from the fact that the coastline is of more limited extent than the interior4 ,altogether the carets offer to our inspection glosses in finer print upon the general text of the canals4 ,thought upon what they show takes us a step farther toward the solution of the strange riddle of this other world1 a riddle which he who runs may not read1 still less scout1 and which only reasoning1 without prejudice or partiality1 can unravel4 ,,chapter ,,xxii ,,the ,,canals ,,photographed ,photography holds to-day a place of publicity in the exposition of the stars4 ,directed by ,draper to the heavens thirty-four years ago1 the camera recorded then the first picture ever taken of the moon4 ,from this initial peering into celestial matters1 practice has progressed until now the dry plate constitutes one of the most formidable engines in astronomic research4 ,not most effectively1 however1 in the field which might have been predicted4 ,beautiful as the lunar presentment was1 as a presentiment of what was coming1 it pointed astray4 ,for it is not in lunar portrayal1 superbly as its crater walls in crescent chiaroscuro or its crags that cast their tapering shadows athwart the dial of its plains stand out in the latest photographs of our satellite1 that the camera's greatest service has since been done4 ,impressive as they are1 these pictorial triumphs are chiefly popular1 and appeal on their face to layman and scientist alike4 ,not in the nearest to us of the orbs of heaven1 but in the most remote has celestial photography's most prolific field been found to lie4 ,its province has proved preminently the stars1 especially the farthest off1 and that star-dust1 the nebul1 from out of which the stars are made4 ,reason for this explains at once its efficiency and its limitations4 ,its rival1 of course1 is the eye4 ,it is as regards the eye that its comparative merits or demerits stand to be judged4 ,now1 thus viewed1 its superiority in one respect is unquestionable2 it simply states facts4 ,but though it cannot misinform1 it can color its facts by giving undue prominence to the effect of some rays and suppressing the evidence of others1 so that its testimony is not1 it must be remembered1 always in accord with that of human vision4 ,speaking broadly1 however1 it is so little complicated a machine as to register its results with more precision than the retina4 ,the evidence of the camera has thus one important advantage over other astronomic documents3 it is impersonally trustworthy in what it states4 ,bias it has none1 and its mistakes are few4 ,imperfections1 indeed1 affect it1 but they are of purely physical occasion and may be eliminated or accounted for as well by another as by the photographer himself4 ,in trustworthiness1 then1 so far as it goes1 it stands commended2 not so much may be said of its ability4 ,this depends upon the work to which it is put4 ,in certain lines it asserts preminence2 in certain others it is so far behind as to be out of the race4 ,the reason for both is one and the same1 for1 as the ,french would say3 ,it has the faults of its quality4 ,the very trait that fits it for one function1 bars it from the other4 ,this excellence is that by which the tortoise outstripped the hare1--a plodding perseverance4 ,far less sensitive than the retina the dry plate has one advantage over its rival1--its action is cumulative4 ,the eye sees all it can in the twentieth of a second2 after that its perception1 instead of increasing1 is dulled1 and no amount of application will result in adding more4 ,with the dry plate it is the reverse4 ,time works for1 not against it4 ,within limits1 themselves long1 light affects it throughout the period it stands exposed and1 roughly speaking1 in direct ratio to the time elapsed4 ,thus the camera is able to record stars no human eye has ever caught and to register the structure of nebul the eye tries to resolve in vain4 ,where illumination alone is concerned the camera reigns supreme2 not so when it comes to a question of definition4 ,then by its speed and agility the eye steps into its place1 for the atmosphere is not the void it could be wished1 through which the light-waves shoot at will4 ,pulsing athwart it are air-waves of condensation and rarefaction that now obstruct1 now further1 the passage of the ray4 ,by the nimbleness of its action the eye cunningly contrives to catch the good moments among the poor and carry their message to the brain4 ,the dry plate by its slowness is impotent to follow4 ,to register anything1 it must take the bad with the better to a complete confusion of detail4 ,for the air-waves throw the image first to one place and then to another1 to a blotting of both4 ,all of which renders the stars1 where lighting counts for so much and form for so little1 the peculiar province of celestial photography4 ,with the study of the surfaces of the planets the exact contrary is the case4 ,with most of them illumination is already to be had in abundance2 definition it is that is desired4 ,what succeeds so excellently with the stars is here put to it to do anything at all4 ,at its best1 the camera is hopelessly behind the eye when it comes to the decipherment of planetary detail4 ,to say that the eye is ten times the more perceptive is not to overstep the mark4 ,to try1 therefore1 here to supplant the eye by the camera is time thrown away4 ,of scant importance to the expert in such matters as ,mars1 there is a side of the subject in which service might be hoped of it3 that of elementary exposition4 ,congenitally incapable of competing with the eye in discovery1 the most that1 by any possibility1 could be looked for would be a recording of the coarser details after the fact4 ,for this reason it had long been a purpose at ,flagstaff to photograph some at least of the canals4 ,but the project seemed chimerical4 ,to get an image suitable at all some seconds of exposure would be required1 and during such time the shifting air-waves would blur the very detail desired to be got4 ,it was a problem of essential premises mutually annihilative4 ,the more the would-be photographer should avoid the one2 the more he would fall into the other4 ,nevertheless the thing was tried in #aija4 ,in #aijc the subject was taken up by ,mr4 ,lampland1 then new at the observatory4 ,the results were better than those of two years before1 the images more clear-cut but still incommunicable of canals4 ,still they were satisfactory enough to spur to increased endeavor1 and during the following interopposition preparations were made to grapple with the planet as successfully as could be devised at its next return4 ,this happened in ,may1 #aije4 ,it then showed a disk only #ag in diameter1 or #a_/abj that of the moon1--and this disk ,mr4 ,lampland attacked with the #bd-;inch and a negative amplificator that increased the focal length of the former to #adc feet4 ,at such focus the planet's image was received upon the plate4 ,everything that could conduce to success had been put in requisition4 ,to this end of better definition the color curve of the objective was first got1 and for it a special color screen constructed by ,wallace4 ,in spite of its name no achromatic is so in fact1 but brings rays of different tint to different focus4 ,the color curve shows where these severally lie1 and the color screen1 a chemically tinted piece of glass1 is to absorb all those which would blur the image by having a different focus from the ones retained4 ,next1 all manner of plates were tried4 ,for in these again it was necessary to reconcile two contradictory characters1 a rapid plate and a well-defining one4 ,for the coarser the grain the speedier the plate2 and coarse grain disfigures the detail4 ,both qualities on so small an image were obligatory and yet both could not be got4 ,then the clock had to be as smooth-running as possible4 ,so by a suggestion of ,mr4 ,cogshall's one was obtained that filled this requisite1 a new form of conical pendulum4 ,upon this a further refinement was practiced4 ,ordinarily clockwork is timed to follow the stars2 this was altered to follow the planet1 and so keep it more nearly motionless while its picture was being taken4 ,then the device of capping down the telescope to suit the air-waves1 which had been found so effective to the bringing out of fine detail1 was put in practice4 ,lastly1 all developers were tried1 and those found suited to the finest work were used4 ,many pictures were taken on each plate one after the other1 both to vary the exposure and to catch such good moments as might chance4 ,seven hundred images were thus got in all2 the days of best definition alone being utilized4 ,the eagerness with which the first plate was scanned as it emerged from its last bath may be imagined1 and the joy when on it some of the canals could certainly be seen4 ,there were the old configurations of patches1 the light areas and the dark1 just as they looked through the telescope1 and never till then otherwise seen of human eye1 and there more marvelous yet were the grosser of those lines that had so piqued human curiosity1 the canals of ,mars4 ,he who ran might now read1 so that he had some acquaintance with photography4 ,by ,mr4 ,lampland's thought1 assiduity1 and skill1 the seemingly impossible had been done4 ,after the initial success was thus assured1 plates were taken at other points around the planet and other well-known features came out2 8continents0 and 8seas10 8canals0 and 8oases10 the curious geography of the planet printed for the first time by itself in black and white4 ,by chance on one of the plates a temporal event was found registered too1 the first snowfall of the season1 the beginning of the new polar cap1 seen visually just before the plate happened to be put in and reproduced by it unmistakably4 ,upon the many images thirty-eight canals were counted in all1 and one of them1 the ,nilokeras1 double4 ,thus did the canals at last speak for their own reality themselves4 ,,part ,,iii ,,the ,,canals ,,in ,,action ,,chapter ,,xxiii ,,canals3 ,,kinematic ,so far in our account of the phenomena we have regarded the lines1 the spots1 and everything that is theirs solely from the point of view of their appearance at any one time4 ,in other words1 we have viewed them only from a static standpoint4 ,in this we have followed the course of the facts1 since in this way were the canals first observed4 ,we now come to a different phase of the matter1--the important disclosure1 with continued looking1 that these strange things show themselves to be subject to change4 ,that is1 they take on a kinematic character4 ,this at once opens a fresh field of inquiry concerning them and widens the horizon of research4 ,it increases the complexity of the problem1 but at the same time makes it more determinate4 ,for while it greatly augments the number of facts which must be collected toward an explanation of what the things are1 these once acquired1 it narrows the solution which can apply to them4 ,the fact of change in the ,martian markings forces itself upon any one who will diligently study the planet4 ,he will be inclined at first to attribute it to observational mistakes of his own or his predecessor's making1 preferably the latter4 ,but eventually his own delineations will prove irreconcilable with one another1 and he will then realize the injustice of his inference and will put the cause1 where indeed it rightly belongs1 on the things themselves4 ,confronted by this fact he will the more fully appreciate how long and systematic must be the study of him who would penetrate the planet's peculiarity4 ,just as the recognition of something akin to seasonal change came to ,schiaparelli1 because of his attending to the planet with an assiduity unknown to his predecessors2 so it became evident that to learn the laws of these changes and from them the meaning of the markings1 there was necessary as full and as continuous a record of them as it was possible to obtain4 ,for this end it was not enough to get observations from time to time1 however good these might be1 but to secure as nearly as might be a complete succession of such1 day after day1 month after month1 and opposition after opposition4 ,the outcome justified the deduction4 ,and it is specially gratifying to realize that to no one have the method and the results thus obtained appealed with more force than to ,schiaparelli himself4 ,perseverance in scanning the disk long after the casual observer had considered it too far away for observational purposes1 resulted in ,schiaparelli's detection of the canals1 and this through a characteristic of theirs destined to play a great part in their history1 their susceptibility to change4 ,he tells us in his ,memoria ,i how ,aeria and the adjoining regions showed blank of any markings while the planet was near in #ahgg and the disk large and well shown1 and then how1 to his surprise1 as the planet got farther away and the disk shrank1 lines began to come out in the region with unmistakable certainty4 ,thus to the very variability which had hidden them to others was due in ,schiaparelli's hands their initial recognition4 ,flux affecting the canals was apparent from the outset of my own observations4 ,no less the subject of transformation than the large dark regions was the network of tenuous lines that overspread them4 ,at times they were very hard to make out1 and then again they were comparatively easy4 ,distance1 instead of rendering them more difficult1 frequently did the reverse4 ,nor was the matter one of veiling4 ,neither our own atmosphere nor that of ,mars showed itself in any way responsible for their temporary disappearance4 ,it was not always when our atmospheric conditions were best that the lines stood out most clearly1 and as to ,martian meteorology there was no sign that it had anything whatever to do with the obliteration4 ,long before the canals were dreamt of1 veiling by ,martian clouds or mist had been considered the cause of those changes in the planet's general features1 which are too extensive and deep-toned wholly to escape observation even though none too clearly seen4 ,it was early evident to me that they were not the cause of general topographic change1 and equally clearly as inoperative in those that affected the canals4 ,in short1 nothing extrinsic to the canal caused its disappearance2 whatever the change was1 its action lay intrinsic to the canal itself4 ,on occasion canals in whole regions appeared to be blotted out4 ,the most careful scrutiny would fail to disclose them1 where some time before they had been perfectly clear4 ,and this though distance was at its minimum and definition at its best4 ,even the strongest marked of the strange pencil lines would show at times only as ghosts of their former selves1 while for their more delicate companions it taxed one's faith to believe that they could ever really have existed4 ,illumination was invoked to account for this1 and plays a part in the effect undoubtedly4 ,for at plumb opposition the centre of the disk for two or three years has shown less detail than before and after that event4 ,this is probably due not1 as with the moon1 to the withdrawal of shadows1 but to the greater glare to which the disk is then subjected4 ,but this is not the chief cause of the change4 ,still more striking and unaccountable was the fact that each canal had its own times and seasons for showing or remaining hid4 ,each had its entrances upon the scene and its exits from it4 ,what dated the one left another unaffected4 ,the ,nilokeras was to be seen when the ,chrysorrhoas was invisible1 and the ,jamuna perfectly evident when the ,indus could scarcely be made out4 ,illustration3 ,showing seasonal change4 ,i4 ,so much shows in the two drawings here reproduced4 ,the increase of the ,ganges and the advent of the ,chrysorrhoas are noticeable in the second over the first4 ,illustration3 ,showing seasonal change4 ,,ii4 ,seasonal changes seemed the only thing to account for the phenomena4 ,and in a general sense this was undoubtedly the explanation4 ,to learn more about the matter1 to verify it if it existed1 and to particularize it if possible1 ,i determined to undertake an investigation permitting of quantitative precision in the case4 ,a method of doing this occurred to me which would yield results deserving of consideration from the amount of data upon which each was based and capable of being compared with one another upon an equal footing from which relative information could be derived4 ,it seemed wise to determine from the drawings the degree of visibility of a given canal at different seasons of the ,martian year1 and then to do this for every important canal during the same period of time4 ,the great number of the drawings suggested this use to which they might be put4 ,for from a great accumulation of data a set of statistics on the subject could be secured in which accident or bias would be largely eliminated and the telling effect of averages make itself felt4 ,to render this possible it was necessary that the drawings should be alike numerous1 consecutive1 and extended in time4 ,these conditions were fulfilled by the drawings made by me at the opposition of #aijc4 ,three hundred and seventy-two drawings had then been secured1 and they covered between them a period of six months and a half4 ,they were also as consecutive as it was possible to secure4 ,during a part of the period the planet was seen and drawn at every twenty-four hours1 from ,april #e1 namely1 to ,may #bf1 or for forty-six consecutive days4 ,though the rest of the time did not equal this perfection1 no great gap occurred1 and one hundred and forty-three nights were utilized in all4 ,furthermore1 as these drawings were all made by one man1 the personal equation of the observer--a very important source of deviation where drawings are to be compared--was eliminated4 ,but even this does not give an idea of the mass of the data4 ,for by the method employed about #ajj drawings were used in the case of each canal1 and as #aji canals were examined this gave #aj1ijj separate determinations upon which the ultimate result depended4 ,that each of these determinations was independent of the others will appear from a description of the method itself on which the investigation was conducted4 ,to understand that method one must begin a little way back4 ,as the two planets1 ,mars and the ,earth1 turn on their axes the parts of their surfaces they present to each other are constantly changing4 ,for a feature on ,mars to be visible from a given post on earth1 observer and observed must confront each other1 and1 furthermore1 it must be day there when it is night here4 ,but1 as ,mars takes about forty minutes longer to turn than the ,earth1 such confronting occurs later and later each night by about forty minutes1 until finally it does not occur at all while ,mars is suitably above the horizon2 then the feature passes from sight to remain hidden till the difference of the rotations brings it round into view again4 ,there are thus times when a given region is visible1 times when it is not1 and these succeed each other in from five to six weeks1 and are called presentations4 ,for about a fortnight at each presentation a region is centrally enough placed to be well seen2 for the rest of the period either ill-placed or on the other side of the planet4 ,if a marking were always salient enough it would appear in every drawing made of the disk during the recurrent fortnights of its display4 ,if it were weaker than this1 it might appear on some drawings and not on others1 dependent upon its own strength and upon the definition at the moment1 and we should have a certain percentage of visibility for it at that presentation4 ,while if it changed in strength between one presentation and the next1 the percentage of its recording would change likewise4 ,definition of course is always varying1 but if its value be noted at the time of each drawing this factor may be allowed for more or less successfully4 ,making such allowance1 together with other corrections to produce extrinsic equality1 such as the planet's distance1 which we need not enter upon here1 we are left with only the marking's intrinsic visibility to affect the percentages2 that is1 the percentages tell of the changes it has successively undergone and give us a history of its wax and wane4 ,from drawings accurately made it is possible to add to the accuracy of the percentage by noting in each1 not only the presence or absence of the marking1 but the degree of strength with which it is represented4 ,this was done on the final investigation in the present case1 and it was interesting to note how little difference it made in the result4 ,the longitude of each canal was known1 and the longitude of the central meridian of each drawing was always calculated and tabulated with the drawing1 so that it was possible to tell which drawings might have shown the canal4 ,only when the position of the canal was within a certain number of degrees of the centre of the drawing 7#fj7 was the drawing used in the result1 allowance being duly made for the loss upon the phase side4 ,each drawing1 it should be remembered1 was as nearly an instantaneous picture of the disk as possible4 ,it covered only a few minutes of observation1 and was made practically as if the observer had never seen the planet before4 ,in other words1 the man was sunk in the manner4 ,such mental effacement is as vital to good observation as mental assertion is afterward to pregnant reasoning4 ,for a man should be a machine in collecting his data1 a mind in cordinating them4 ,to reverse the process1 as is sometimes done1 is not conducive to science4 ,when the successive true percentages of visibility of a given canal had thus been found1 they were plotted vertically at points along a horizontal line corresponding in distance from the origin to the number of days after 7or before7 the summer solstice of the ,martian northern hemisphere4 ,the horizontal distance thus measured the time while the vertical height gave the relative visibility4 ,the points so plotted were then joined by a smooth curve4 ,this curve reproduced the continuous change in visibility undergone by the canal during the period under observation4 ,it gave a graphic picture of the canal's change of state4 ,it seemed1 therefore1 proper to call it the canal's cartouche or sign manual4 ,in this manner were obtained the cartouches of #aji canals4 ,now1 as the presence or absence of any canal in any drawing was entirely irrespective of the presence or absence of another1 each such datum spoke only for itself1 and was an entirely independent observation4 ,the whole investigation thus rested on #aj1ijj completely separate determinations1 each as unconditioned by the others as if it existed alone4 ,as every factor outside of the canal itself which could affect the latter's visibility was taken account of1 and the correction due to it as nearly as possible applied before the cartouches were deduced1 the latter represent the visibility of the canal due to intrinsic change alone4 ,in other words1 they give not the apparent only but the real history of the canal for the period concerned4 ,important disclosures result from inspection of the cartouches4 ,this we shall perceive by considering what different curves mean in the case4 ,if the canal were an unchangeable phenomenon1 for any reason whatever1 its cartouche would be a straight line parallel to the horizon of the diagram4 ,this is evident from the fact that the visibility would then never vary4 ,if1 on the other hand1 it were waxing and waning1 and the wax or wane were uniform1 the cartouche would be a straight line inclined to the horizontal2 rising if the canal were increasing1 falling when it decreased4 ,lastly1 if the rate of change itself varied1 the cartouche would be a curve concave or convex to the line denoting the time1 according as the rate of change of the growth or decay grew greater or less4 ,to see this the more clearly1 we may set over against the cartouche the canal character it signalizes3-- ,cartouche4 ,character4 ,a horizontal straight line4 ,canal invariable4 ,a straight line tilted up on the right4 ,canal increasing steadily4 ,a straight line tilted up on the left4 ,canal decreasing steadily4 ,a curved line descending1 concave from ,canal decreasing1 but more above4 and more slowly4 ,a curved line ascending1 concave from ,canal increasing1 but more above4 and more rapidly4 ,a curved line descending1 convex from ,canal decreasing more and above4 more rapidly4 ,a curved line ascending1 convex from ,canal increasing more and above4 more slowly4 ,a curved line first descending1 then ,canal decreasing more and ascending1 concave from above more slowly to a minimum1 throughout4 thence increasing more and more rapidly4 ,a curved line first descending1 then ,canal increasing more and ascending1 convex from above more slowly to a maximum1 throughout4 thence decreasing more and more rapidly4 ,if the cartouche first falls and then rises1 this shows the canal to have passed through a minimum state at the time denoted by the point of inflection2 if it rises first and falls afterward1 this betokens in the same way a maximum4 ,thus the cartouches reveal to us the complete history of the canals1--what changes they underwent and the times at which these occurred4 ,the cartouche1 then1 is the graphic portrayal of the canal's behavior4 ,it not only distinguishes at once between the dead and the living1 as we may call the effect of intrinsic change1 but it tells the exact character of this change1--the way it varied from time to time1 the epoch at which the development was at its minimum or its maximum for any given canal1 and lastly1 its actual strength at any time1 thus giving its relative importance in the canal system4 ,for the height of the curve above the diagrammatic horizon marks the absolute as well as the relative visibility and enables us to rank the canals between themselves4 ,now1 the first point it furnishes a criterion for is the real or illusory character of the canals4 ,if a line be due to illusion1 whether optical or physical1 it can vary only from extrinsic cause1 since it has no intrinsic existence4 ,if1 therefore1 all extrinsic cause be allowed for1 the cartouche of this ghost must needs be a horizontal straight line4 ,even if the extrinsic factors to its production be imperfectly accounted for1 their retention could only cause systematic variations from the straight line in all the lines1 which would themselves vary systematically1 and these factors could therefore be detected4 ,this criterion is absolute4 ,unless all the cartouches were approximately straight lines1 no illusion theory of any kind whatever could explain the facts4 ,even then the lines might all be real2 for unchangeable reality would produce the same effect on the cartouches as illusion4 ,in the case therefore of horizontal straight line cartouches1 we should have no guarantee on that score of reality or illusion2 but1 on the other hand1 curves or inclined straight lines in them would be instantly fatal to all illusion theories4 ,turning now to the #aji cartouches obtained in #aijc1 the first point to strike one's notice is that all but three of them are curves and that even these three must be accepted with a caveat4 ,here1 then1 the cartouches dispose once and for all of any and every illusion theory4 ,they show conclusively that the canals are real objects which wax and wane from some intrinsic cause4 ,the second result afforded by the cartouches is not of a destructive1 negative character1--however valuable the destruction of bars to knowledge may be1--but of a constructive1 positive one4 ,it does not1 like the first1 follow from mere inspection1 but is brought to light only by comparison of all the cartouches4 ,in a positive way1 therefore1 its testimony is as conclusive as it was in a negative direction4 ,for that #aj1ijj separate and independent data should result in a general law of development through either conscious or unconscious bias1 when those data would have to be combined in so complicated a manner for the result to emerge as is here the case1 is impossible4 ,chance could not do it and consciousness would require a cordinate memory1 to which ,murphy's nine games of chess at once would be child's play4 ,of the #aji canals examined #ajf showed by their cartouches that they had been during the whole or a part of the period in a state of change4 ,but the change was not the same for all4 ,in some the minimum came early2 in others1 late4 ,some decreased to nothing and stayed there2 others increased from zero and were increasing still at the time observations closed4 ,latitude proved the means of bringing comparative order out of the chaos4 ,when the canals were ranged according to their latitude on the planet1 a law in their development came to light4 ,to understand it1 the circumstances under which the canals were presented must be considered as regards the then season of the planet's year4 ,in #aijc the planet passed on ,february #bh through the point of its orbit where the summer solstice of the northern hemisphere occurs4 ,one hundred and twenty-six days later took place the first snowfall in the arctic and subarctic regions1 an event that denoted the beginning of the new polar cap2 from which date the snow there gradually increased4 ,its autumnal equinox the planet did not reach till ,august #bi4 ,now1 the canals were observed from thirty-six days before the summer solstice of the northern hemisphere to one hundred and forty-seven days after that event4 ,we may tabulate the dates as follows3-- ,,day ,,from ,,vernal ,,corresponding ,,summer ,,solstice ,,longitude ,,date ,,on ,,earth ---------------------------------------- --- -#cj #gg ,june #i #j #ij ,june #bb #cj #ajc ,july #f #fj #aag ,july #bj #ij #aca ,august #d #abj #adf ,august #bj #aej #afb ,september #e ,the vernal longitude is the longitude of the planet in its orbit reckoned from the vernal equinox4 ,from the table it appears that the cartouches cover the development of the canals from about ,june #f to ,september #a of the ,martian northern hemisphere for the current but to us undated year1 ab ,marte condita4 ,the #aji canals included all the more conspicuous canals on the planet at that opposition1 all those that lent themselves by the sufficient frequency with which they were seen to a statistical result4 ,they lay spread all the way between the edge of the polar cap in latitude #hg north to the extreme limit south1 at which the then tilt of the north pole toward the earth permitted of canal recognition4 ,this southern limit was in about latitude #ce south4 ,farther south than this vision became too oblique1 amounting as it did1 with an adverse tilt of twenty-five degrees to start with1 to something over sixty degrees1 for detection of such fine markings to be possible4 ,between the two limits thus imposed1 by the perpetual snow on the one side and the observational tilt on the other1 the #aji canals were distributed by zones as follows3-- ,,zone ,,latitude ,,number ,,of ,,canals ---------------------------------------- --- ,north ,polar #hg ,n4-#gh ,n4 #a ,arctic #gh ,n4-#ff ,n4 #i ,sub-,arctic #ff ,n4-#ea ,n4 #i ,north ,temperate #ea ,n4-#cg ,n4 #aa ,north ,sub-,tropic #cg ,n4-#bd ,n4 #ah ,north ,tropic #bd ,n4-#ab ,n4 #ba ,north ,equatorial #ab ,n4- #j ,n4 #ad ,south ,equatorial #j ,n4-#ab ,s4 #ag ,south ,tropic #ab ,s4-#bd ,s4 #g ,south ,sub-,tropic #bd ,s4-#cg ,s4 #b ,as the latitude of a canal in the investigation was taken as that of its mid-point1 such being the mean value of its successive parts1 the latitudes about which information was obtained lay within the limits given above1 the most northern canal1 the ,jaxartes ,n having for its mid-latitude #gh north1 and the most southern1 the ,nectar1 that of #bg south4 ,the zones comprised each a belt of territory about thirteen degrees wide1 the first being less solely because in part occupied by the permanent polar cap4 ,the curves of all the canals in a given zone have been combined into a mean curve or cartouche for that zone2 and then the cartouches for the several zones have been represented and ranged according to latitude on the accompanying plate4 ,consideration of these mean canal cartouches is very instructive4 ,in the first place not one of them is a straight line1 either horizontal or inclined4 ,all are curves and1 with the exception of the top one1 all show a minimum or lowest point during the period under observation4 ,from this point they rise with the time1 or to the right on the plate4 ,a black star marks this minimum1 and is found farther and farther to the right as one goes down the plate2 that is1 as one travels from the neighborhood of the arctic regions down to the equator and then over into the planet's southern hemisphere4 ,drawing now a line approximately through the stars and remembering that the minimum means the date at which the canal started to develop1 we see that the canal development began at the border of the north polar cap and thence continued down the disk over the planet's surface1 as far as observation permitted the surface to be seen1 which was some thirty-five degrees into the other hemisphere4 ,this is the first broad fact disclosed by the cartouches4 ,illustration3 ,,mean ,,canal ,,cartouches ,p4,l4 ,furthermore1 the development took place at an approximately uniform rate4 ,this is shown by the fact that the line passing through the black stars is approximately straight2 for such straightness means that progression down the disk as measured by the latitude bore throughout the same ratio to the time elapsed4 ,looking at them again we notice that the three topmost cartouches1 those of the north polar1 arctic1 and sub-arctic canals respectively1 dip at the right before the end of the observations1 while the other seven were still rising when those observations were brought to a close4 ,a reason for this1 or at least a significant coincidence1 is to be found in the dotted line pendent from the top of the table and labelled 8,first ,frosts40 ,this dotted line denotes the date at which the first extensive frost occurred in the polar regions2 for even before this time patches of white had appeared north of the ,mare ,acidalium1 denoting the on-coming of the cold4 ,the frost did not last but came and went and came again just as it does on earth1 growing more insistent and long-lived at each fresh fall4 ,its sphere of operation was confined to the three zones in question4 ,even these zones it by no means covered1 merely blotching them in places with fungi-like patches of frost4 ,beyond them south it never extended during the period of the observations2 indeed1 it hardly entered the sub-arctic zone at all at this very beginning of the polar winter4 ,for it was only ,august #bj then4 ,the coincidence of the isotherm as betrayed by the deposition of frost with the dividing line between the canal-development curves that dip down at this season and those that still continue to rise is suggestive4 ,it becomes all the more so when the three cartouches are considered seriatim4 ,the most polewards1 the north polar one1 had sunk to zero sometime before the first extensive frost occurred2 the second1 the arctic1 did so later than its northern neighbor1 probably just before the epoch in question2 while the third1 practically outside the zone of deposition1 was behind both the others in its descent4 ,inspection of the drawings upon which the cartouches are based confirms an inference deduced from this3 that it was cold that killed1 not frost that covered1 them1 which was responsible for their obliteration4 ,the drawings show that the canals ceased to be seen before the white patches were evident4 ,now this would be the exact behavior of vegetation4 ,it would be killed1 turned brown by freezing1 and so rendered invisible to us against its ochre desert background1 before the cold had grown intense enough to cover that ground with a solid white carpet of frost4 ,at the opposition of #aije1 however1 the extreme northern canals were visible after the snow had covered all the country about them1 being evident as lines threading the new cap4 ,these three cartouches furthermore show each a maximum1 and what is significant the maximum occurs later in time for each1 according as the zone lies remote from the pole4 ,a red star marks this maximum and shows that the time of greatest development for the three zones was respectively3-- #da days after the summer solstice for the ,north ,polar4 #fa days after the summer solstice for the ,arctic4 #ie days after the summer solstice for the ,sub-,arctic4 ,we now pass to the other curves1 those that were unaffected by cold4 ,though in these the minima themselves show the law of latitudinal progression1 the wavelike character of the advance is even better disclosed by the curves4 ,as the eye follows them down the page1 the advance of the wave to the right is plainly apparent4 ,the slope of the wave is much the same for all1 implying that a like force was at work successively down the latitudes4 ,it will be noticed next that in all the mean cartouches the gradient is greater after the minimum than before it4 ,the curves fall gently to their lowest points and rise more steeply from them4 ,such profile indicates that the effects of a previous force were slowly dying out down to the minimum and that then an impulse started in to act afresh4 ,this explains the attitude of the canals that died out4 ,in them the effect of the old force shows as in the others1 but no impulse came in their case to resuscitation4 ,it seems possible to trace this force to an origin at the south4 ,for beginning with the north sub-tropic zone the gradient on the left shows less and less steep southward to the south sub-tropic zone4 ,such a dying-down swell is what should be looked for in an impulse which had travelled from the south northward1 since the wave would affect the more northern zones last1 and less of a calm period would intervene between the two impulses from opposite poles4 ,the cartouches1 then1 state that the canals began to develop after the greatest melting of the polar cap had occurred2 that this development proceeded down the latitudes to the equator1 and then not stopping there advanced up the latitudes of the other hemisphere4 ,in the next place they show that in the arctic region the development was arrested and devolution or decay set in as it began to get cold there1 the most northern canals being affected first4 ,finally1 that a similar wave of evolution had occurred from the opposite pole some time before and had then passed away4 ,and this evidence of the cartouches is direct1 and independent of any theory4 ,,chapter ,,xxiv ,,canal ,,development ,individually ,instanced ,as an interesting instance of the law of development we may take the career of the ,brontes during this same ,martian year2 the ,brontes witnessing individually to the same evolutionary process that the canals collectively exhibit4 ,the ,brontes is one of the most imposing canals upon the planet4 ,it is not so much its length which renders it a striking object1 though this length is enough to entitle it to consideration1 being no less than #bddj miles4 ,its direction is what singles it out to notice1 for it runs almost north and south4 ,for this reason it swings into a position to hold the centre of the stage for a time with the precision of a meridian1 as the planet's rotation turns its longitude into view4 ,the points which it connects help also to add to its distinction4 ,for the ,sinus ,titanum at its southern end and the ,propontis at its northern are both among the conspicuous points of the disk4 ,the latter is but twelve degrees farther east than the former1 while it is sixty-six degrees farther north4 ,this long distance1--from nearly the line of the tropics in the southern hemisphere to mid-temperate regions of the northern1--the canal runs in an absolutely straight course4 ,its north and south character commends it for any investigation of canal development1 since it runs in the general direction that development takes4 ,its great latitudinal stretch further fits it for a recorder of changes sweeping down the disk2 so that both in direction and length it stands well circumstanced for a measure of latitudinal variations4 ,the fact that it is usually a fairly conspicuous canal does not detract from its virtue in this respect4 ,it was first recognized at ,flagstaff in #ahid4 ,but once realized1 so to speak1 it was possible to identify it with a canal seen by ,schiaparelli and supposed by him to be the ,titan2 indeed1 it played hide and seek with that canal throughout his drawings4 ,in #ahid both it and the ,titan were so well seen that its separate existence was unmistakable1 causing it to be both recognized and named4 ,it is1 like the ,titan1 one of the sheaf of canals descending the disk from the ,sinus ,titanum1 and lies just to the east of the ,titan in the bunch4 ,in #ahif it was also prominent2 and at both these oppositions most so from its southern end1 its northern one being more or less indefinite1 especially in #ahid4 ,in #aija it was not the same4 ,instead of being the conspicuous canal it had been in earlier years1 it was now so faint as with difficulty to be made out4 ,it remained so to the close of observations4 ,it was now under suspicion4 ,its behavior in #ahif-ahig had led to the supposition that not only were seasonal changes taking place in it1 but that those changes were such as to point to a law in the case with which its conduct in #aija fayed in4 ,the suspicion did not1 however1 become a certainty till the opposition of #aijc4 ,the length of time during which the disk was then kept under scrutiny resulted in the method of its metamorphosis being discovered4 ,illustration3 ,i4 ,february #be4 ,at the very start of observations its longitude chanced to be nearly central and it was made out2 but so far off was the planet that only its northern part could be detected1 because1 as afterward appeared1 this part was the stronger1 the canal being decidedly inconspicuous1 whereas other canals1 the northern and even the ,pallene and the ,dis1 were strongly marked4 ,at the next presentation the planet was nearer1 and details previously hidden for the distance now came out4 ,among them was the ,brontes1 which1 showing better than in ,january1 could be traced all the way to the ,sinus ,titanum4 ,a drawing 7,i7 made on ,february #be and reproduced in the text shows its appearance at the time4 ,its emergence under neared conditions only served to accentuate its relative inconspicuousness1 for it showed now notably inferior to the northern canals1 and this not only in the matter of general visibility1 but in the character it displayed4 ,it was a line of hazy definition1 contrasting thus with the sharp dark forms of its northern neighbors4 ,illustration3 ,,ii4 ,march #cj4 ,illustration3 ,,iii4 ,april #c4 ,as the planet steadily approached the earth1 and the canals to the north became better and better seen1 the ,brontes instead of sharing in the general improvement did exactly the opposite4 ,it grew less visible when it should have grown more so1 if distance had been the cause of its appearance4 ,it was now only to be seen at the north1 even when it was seen at all2 a state of things exemplified in ,drawings ,,ii and ,,iii4 ,illustration3 ,,iv4 ,may #d4 ,as the planet now went away and detail should have dimmed1 the ,brontes proceeded to do the opposite4 ,one had almost said it was actuated by a spirit of contrariety4 ,for now when it had reason to grow faint it grew in conspicuousness2 just as1 before1 when it should have become evident1 it had declined4 ,distinctly farther off and smaller as the planet was at the next presentation1 the ,brontes had clearly developed both in tone and in the amount of it visible4 ,this was in ,may 7,drawings ,,iv and ,v74 ,in ,june bad seeing prevented good observations1 but in ,july1 ,drawing ,,vi1 when the region again came round1 the ,brontes1 in spite of the then greatly increased distance1 asserted itself so strongly that even in not very good seeing its presence could not be passed by4 ,illustration3 ,v4 ,may #g4 ,this contrariety of behavior had about it one very telling feature4 ,that the canal waxed or waned in exact opposition to distance and even toward the last to seeing too1 showed conclusively that neither distance nor definition could in any way be held responsible for its metamorphoses4 ,a very fortunate circumstance1 this of the observations1 for it directly eliminated size of disk1 phase1 and seeing1 for which correction are none too easy to make1 and which in the minds of the sceptical could always remain as unexplained possibilities of error4 ,illustration3 ,,vi4 ,july #ah4 ,the mean-canal cartouches show synthetically1 and all the more conclusively for being composite1 the laws of the flux of the canals4 ,something more of vividness1 however1 is imparted by the actual look of one of the constituents during the process4 ,it is the difference between seeing a composite picture made from a given group of men and the gazing on the actual features of any one of them4 ,so much is gained by the drawings across the page of the ,brontes at different stages of its evolution during the period here concerned4 ,but in another way1 too1 the one canal may be made to yield a more lifelike representation of the process than a number taken together are capable of affording4 ,in the mean-canal cartouches each canal is treated as an entity2 but it is possible to consider a canal by parts1 and by so doing to see it in action1 as it were4 ,it occurred to me to treat the ,brontes in this way4 ,for this purpose ,i divided the canal into sections1 five of them in all1 between the point where it left the ,propontis1 at a spot called the ,propropontis1 to where it ended in the ,sinus ,titanum4 ,the first1 the most northern1 extended as far as ,semnon ,lucus1 the southernmost outpost of the ,propontis congeries of spots4 ,the second continued on from these to ,eleon1 the junction where the ,erebus crossed4 ,the third thence to ,utopia1 where the canal met the ,orcus2 the fourth to an arbitrary point in latitude #h south1 and the fifth and last to the ,sinus ,titanum4 ,the lengths of these sections were respectively3 #ab1 #af1 #ae1 #ab1 and #ac4 ,each of the sections was then treated as if it were a separate canal and its cartouche found4 ,to the cartouches' determination there were available drawings3 ,january #ba-be #ab drawings4 ,february #bc-,march #b #ae drawings4 ,march #bh-;,april #e #ad drawings4 ,april #bf-,may #h #bg drawings4 ,june #c-af #f drawings4 ,july #aa-ba #af drawings4 ------------------- #ij drawings in all4 ,the cartouches are given in the plate opposite1 which is constructed precisely like the one for the mean canal cartouches presented on page #bih4 ,the mid-latitude of the section and its mid-longitude are given in the margin with its description4 ,illustration3 ,,brontes ,showing ,successive ,development ,south ,january to ,july1 #aijc ,p4,l4 ,examining them now we note a family resemblance between the successive cartouches4 ,all sink slowly on the left to rise sharply from their lowest point to the right4 ,such resemblance betokens the action of one and the same cause4 ,next1 although the curves are resemblant1 each has been1 as it were1 sheered to the right as one reads down2 that is1 the action took place later and later as the latitude was north4 ,lastly1 the dying out of a previous impulse can be traced in the cartouches1 which shows that the canals were quickened six months previously from the south polar cap1 as they were now being quickened from the north polar one4 ,,chapter ,,xxv ,,hibernation ,,of ,,the ,,canals ,connected with the conduct of the canals is a phenomenon1 examples of which were early noted in a general way by ,schiaparelli and later1 but of which the full import and exhibition only came to light during the opposition of #aijc by a very striking metamorphosis3 what may be called the hibernation of a canal for a longer or shorter term of years4 ,what observation discloses is certainly curious4 ,for several successive oppositions a canal will be seen in a definite locality1 as regular in seasonal recurrence as it is permanent in place1 a well-recognized feature of the disk4 ,then to one's surprise1 with the next return of the planet1 it will fail to appear1 and will proceed to remain obliterate without assignable cause for many ,martian years1 until as unexpectedly it will be found what and where it was before4 ,neither to deposition of hoar-frost1 such as frequently whitens whole regions of ,mars1 nor to other circumstances can be attributed its disappearance4 ,without apparent reason it simply ceases to be and then as simply comes back again4 ,such bopeep behavior is quite beyond and apart from the seasonal change in visibility1 to which all the canals are by their nature subject4 ,for being creatures of the semi-annual unlocking of the water congealed about the polar caps1 they quicken into growth and visibility1 each in its season1 and as regularly die out again4 ,different1 however1 is the phenomenon to which ,i now refer4 ,in it not a seasonal but a secular change is concerned4 ,the season proper to the canal's increase will recur in due course1 and the canals round about it will start to life1 yet the canal remains unquickened4 ,nothing responds where in years the response was immediate and invariable4 ,the canal lies dormant spite of seasonal solicitation to stir4 ,such curious hibernation was early hinted to the keenness of ,schiaparelli1 and most incomprehensible as well as difficult of verification at that stage the phenomenon was4 ,that the absence was a fact1 however1 he assured himself1 although he was not able to prove an alibi4 ,but at the last opposition an event of the sort occurred which1 from the length of time the planet was kept under observation1 combined with continued suitableness of the seeing1 unmasked the process4 ,in the light of what then happened1 taken in connection with the side-lights thrown upon it by the canal's past and by the knowledge we have meanwhile gained of the planet's physical condition1 the riddle of the phenomenon may in part at least be read1 and most interesting and instructive the reading proves to be4 ,among the initial canals detected by ,schiaparelli1 in #ahgg1 was a tricrural set of lines recalling the heraldic design of three flexed legs joined equiangularly above the knees4 ,it lay to the east of the ,syrtis ,major1 and he called its three members the ,thoth1 the ,triton1 and the ,nepenthes4 ,starting from the head of his gulf of ,alcyonius1 at a point now known to be occupied by the oasis called ,aquae ,calidae1 the ,thoth started south inclining westward as it went1 till in longitude #bfg and latitude #ae north1 it met the ,triton1 which had come from the ,syrtis ,minor with similar westward inclination4 ,to the same point in the same manner came the ,nepenthes4 ,part way along the course of the latter was to be seen a small dark spot1 the ,lucus ,moeris1 which he estimated at four degrees in diameter4 ,some of the markings were easier than others1 the easiest of all being the ,lucus ,tritonis1 a largish dark spot at the common intersection of all three canals2 but that none of the markings were remarkably difficult is sufficiently shown by their detection at this early stage of ,schiaparelli's observations4 ,it is worth noting also that he discovered the southern ones first2 the ,thoth not being seen till ,march1 #ahgh4 ,as his then recognition of these canals witnesses1 they must have been among the most evident on the disk4 ,and the point is emphasized by the fact that he failed at this opposition to detect the ,phison and the ,euphrates as separate markings4 ,much the same the three canals appeared to him at the next opposition of #ahgi1 the ,thoth being seen at its several presentations from ,october #e1 #ahgi1 to ,january #aa1 #ahhj4 ,at the next opposition a noteworthy alteration occurred1 the full significance of which escaped recognition4 ,schiaparelli saw1 at the place where the ,thoth had been1 two lines which he took for a gemination of that canal1 one of which followed the course of the old ,thoth1 while the other went straight from the ,sinus ,alcyonius to the ,little ,syrtis1 or1 more precisely1 to the junction of the ,triton and the ,lethes4 ,it was not the ,thoth1 however1 but something unsuspected1 of more importance4 ,in #ahhd the ,thoth showed really double1 the western line being much the stronger1 8una delle piu grosse linee que si vedessero sul disco40 ,that neither branch went farther than the meeting-place with the ,nepenthes argues that it was indeed the ,thoth that was seen4 ,schiaparelli himself had no doubt on the subject1 although he drew the double canal he saw due north and south from the tip of the ,sinus ,alcyonius to the junction1 but nevertheless along the #bfc meridian4 ,in #ahhf and #ahhh the system was in all essentials1 what it had been in #ahgg and #ahgi1 except that the ,thoth and ,nepenthes were double and were more minutely seen4 ,here1 then1 was a system of canals and spots which for six ,martian years had been a persistent and substantially invariable feature of the ,martian surface4 ,any changes in it had been of a secondary order of importance1 while its general visibility was of the first4 ,it is possible1 then1 to judge of my perplexity when in beginning my observations in #ahid no sign of the system could ,i detect4 ,of neither the ,thoth1 the ,triton1 the ,nepenthes1 nor the ,lucus ,moeris was there trace4 ,and yet1 from the other canals visible1 it was evident that the disk was quite as well seen as it had been by ,schiaparelli4 ,not only were practically all his canals there1 but many much smaller ones were to be made out4 ,and the same was true of the spots1 a host of such not figured by him appearing here and there over the planet's surface4 ,nor was this all4 ,instead of the ,thoth1 another canal showed straight down the disk from the ,syrtis ,minor to the ,aquae ,calidae4 ,this canal was as unmistakable as the ,thoth had been before to ,schiaparelli4 ,it was among the first to be detected1 and continued no less conspicuous to the end1 the dates at which it was seen being ,july #aj1 ,august #ad1 and ,october #ba4 ,i called it the ,amenthes1 identifying it with the canal so named in ,schiaparelli's chart published in ,himmel und ,erde1 of the ensemble of his observations from #ahgg to #ahhh4 ,but in his ,memoirs he never called it so1 seeing it1 indeed1 only in #ahha-ahhb1 and deeming it then the ,thoth4 ,nevertheless1 in #ahid1 it was the conspicuous canal of the region1 and1 what is more1 had come1 as it proved1 to stay4 ,the invisibility of the ,thoth continued for me the same during the succeeding oppositions of #ahif-ahig and #aija4 ,at the former opposition ,i drew it in #ahif on ,july #bh1 ,august #bf1 ,september #b1 ,october #e-i1 seeing it single2 and in #ahig on ,january #ab-ai1 ,february #ba1 and ,march #a4 ,it was single but with suspicions of doubling in ,january1 and was indubitably double in ,february4 ,as for the ,thoth1 ,i had come to consider it and the ,amenthes one1 attributing their diversity of depiction to errors in drawing4 ,for while the ,thoth remained obstinately invisible1 the ,amenthes presented itself as substitute so insistently as to make one of the most obvious canals upon the disk4 ,one exception only was there to this state of things4 ,on ,june #af1 #aija1 my notes contain this adumbration of a something else3 8,amenthes sometimes appeared with a turn to it two-thirds way up2 two canals concave to the ,syrtis ,major40 ,illustration3 ,amenthes alone in ,february4 ,so matters opened at the opposition of #aijc4 ,with the advent of the planet and the presentation in due course of ,libya in ,february1 the ,amenthes duly appeared1 much as it had showed at the opposition before1 only less salient4 ,it was a confused and seemingly narrower double4 ,suspected on the #afth of that month1 it was definitely seen from the #ahth to the #bc;d4 ,of the ,thoth no mention is made either in the notes or in the drawings4 ,when the region came round again1 in ,march1 the ,amenthes was still there1 showing more feebly1 however1 than it had in ,february1 in spite of better seeing and the fact that the planet had considerably neared4 ,clearly the canal was fading out2 a fact further witnessed to by the following note made on ,march #be3 8,throughout this opposition thus far the dark triangle tipped by ,aquae ,calidae has been sharply divided in intensity from the ,amenthes1 which is very narrow and exceedingly faint40 ,still was there no trace of the ,thoth4 ,illustration3 ,amenthes feebler and still alone in ,march4 ,with the ,april presentation entered a new order of things4 ,when the region first became visible1 on the #afth1 the ,amenthes could still be seen and alone2 but on the #aith1 as the relative falling back of the ,martian longitudes swung the region nearer the centre of the disk1 the ,thoth appeared alongside of it4 ,on the #bjth the ,thoth showed alone4 ,unmistakable it was and just as ,schiaparelli had drawn it1 accompanied by the ,triton and the curved ,nepenthes4 ,the thing was a revelation4 ,what before ,i had seen only in the spirit of another's drawings stood there patent to me in the body of my own2 while the ,amenthes1 to which ,i had so long been accustomed1 had vanished into thin air4 ,only a trace of it was now and then to be made out4 ,so startlingly strange was the metamorphosis that ,i could not at first trust my eyes1 and questioned the broken line1 which had replaced the straight1 for some ocular deception4 ,but nothing ,i could do would rectify it4 ,the ,amenthes was gone and the ,thoth stood in its stead4 ,illustration3 ,appearance of ,thoth with ,triton and curved ,nepenthes4 ,amenthes vanished4 ,april #bj4 ,at the next presentation1 ,may #bf to ,june #h1 the phenomena were repeated1 and with increasing clarity4 ,and then of a sudden1 on ,may #bi1 ,i saw the long-given-up ,lucus ,moeris4 ,there it was indubitably4 ,and its definiteness was the most astonishing part of the affair4 ,it was no question of difficult detection4 ,indeed1 ,i had not been on the lookout for it1 having searched the region too often fruitlessly before to have left incentive to search again4 ,and so1 when ,i was not searching1 the thing of its own accord stepped forth to sight4 ,it was a small round dot1 like to any other oasis1 and showed1 as it were1 a black pearl pendent by the ,nepenthes from the ,syrtis's ear4 ,for the ,libyan bay made a dark projection of the sort high up on the ,syrtis's eastern side1 from which the ,nepenthes1 precisely as ,schiaparelli had drawn it1 curved down to the point where the ,thoth and ,triton met4 ,all three canals were geminated1 the gemination being about three degrees wide4 ,illustration3 ,advent of the ,lucus ,moeris4 ,may #bi4 ,and now occurred the last act in the drama4 ,in ,july the ,amenthes reappeared1 showing alongside of the ,thoth-,nepenthes1 and thus removing any possible doubt as to their separate identity4 ,it had1 indeed1 become the stronger of the two1 having gained in strength in the interval between ,june and ,july and the ,thoth-,nepenthes having lost4 ,the lines were in process of relapsing into the status quo ante4 ,had these three presentations not been watched1 the brief apparition of the ,thoth-,nepenthes had been missed and with it the revealing of its curious character1 and of certain deductions thereupon4 ,illustration3 ,amenthes with ,thoth-,nepenthes4 ,july4 ,first among these is a truth of which ,i have long been convinced2 to wit1 that when a seeming discordance arises between the portrayals of a canal1 it is commonly not a case of mistake nor of change1 but one of separate identity4 ,the canal has not shifted its place1 nor has an error been committed2 the fact is that one canal has been observed at one time1 another at another4 ,so it was here1 and thus were the old and the new observations reconciled4 ,there had been no mistake in either4 ,two separate canals accounted for the discrepancy1 and only an unfounded distrust of the accuracy possible in such observations was to blame for any failure to recognize the fact4 ,now1 scrutiny of the notes upon the appearance of the two canals1 together with their labeling by the seasonal longitudes of the planet at the dates they were made1 discloses a curious relation between the two4 ,the seasonal longitudes are important1 as they date the phenomena according to the ,martian calendar4 ,ordered thus1 the successive aspects reveal first a seasonal change in each canal and then over and above this a secular one4 ,and this secular change was such as to cause the two canals to alternate in visibility4 ,when the one was present the other was not1 and vice versa4 ,illustration3 ,,cartouches ,,or ,,curves ,,of ,,visibility ,,of ,,amenthes1 ,,thoth ,,and ,,their ,,combination4 ,we shall see this more clearly and at the same time bring out a curious relation between the two systems1 the broken bow of the ,thoth-,nepenthes-,triton and the straight arrow of the ,amenthes1 while looking at the cartouches of the ,thoth1 the ,amenthes1 and a combination of both given in the plate on previous page4 ,the antithetical character of the two canals is apparent4 ,but what is further interesting1 the combination cartouche of both bears a singular resemblance to that of the mean canal of the north tropic zone1 the zone to which both canals belong4 ,here1 then1 is a combination which is perfectly regular while each of its constituents is anomalous4 ,and now we come to something as important3 at the opposition of #aije the curious alternation metamorphosis was enacted anew4 ,the ,amenthes appeared1 disappeared to be replaced by the ,thoth1 and then reappeared again beside the other4 ,this corroboration of behavior showed the previous observations to have been due to no mistake1 and only served to deepen the interest in this last and more singular phase of canal conduct4 ,,chapter ,,xxvi ,,arctic ,,canals ,,and ,,polar ,,rifts ,last in time but not least in importance of the details of canal development to be detected is one that connects these strange features directly with the melting of the polar caps4 ,the cartouches showed that such connection was to be inferred2 the facts now to be recorded depict it by an identity of place between certain phenomena of the two subjects following one another in order of time4 ,on ,january #h1 #ahig1 while scanning the planet1 ,i was suddenly ware of a rift in the north polar cap4 ,it ran a little to the west of south from where it started in at the cap's edge and went clean through to the limb1 the pole being then slightly tilted away from us4 ,at the time it seemed to be the first rift ever seen in that cap2 but on opening a little later ,schiaparelli's ,memoria ,quarta1 which had just arrived1 the first thing my eye fell on was a drawing of a rift in the north polar cap observed by him when the planet had held the like attitude toward the ,earth thirteen years before4 ,reference to its longitude showed it to be the identical rift1 seen again after all these years and the only one so far seen in the northern cap4 ,at the next opposition more rifts were detected1 one in especial on ,december #bg1 running from ,arethusa ,lucus1 then upon the edge of the cap1 athwart the snow in a northwesterly direction4 ,in the forepart of the opposition of #aija1 which in its ,martian season corresponded to that in #ahig1 when the rift had been observed1 many rifts were detected in the cap1 and among them one traversing the cap north-northeasterly in longitude #acf4 ,so far the season when the cap had been observed was that when the rifts were in process of forming4 ,the ground they and the snow-cap covered had not yet at any opposition been uncovered4 ,it was only when my observations began in the latter half of the opposition of #aija that1 the season on ,mars having so far advanced1 all snow in those latitudes had melted4 ,then appeared1 however1 the canal ,hippalus1 an arctic canal of some importance1 lying on that part of the planet previously occupied by the polar cap4 ,when later studying the observations on the rifts ,i remembered this canal1 and turning to the drawing made some months before to compare the two critically1 discovered that the canal occupied the precise position held earlier by the rift4 ,one had said the rift had never vanished1 but that the white surrounding it had simply turned to ochre4 ,here1 then1 was a striking coincidence of place1 too exact to be the result of chance4 ,impressed by the identity1 ,i examined all the other rifts seen early in #aija1 comparing them with the arctic canals seen later1 to the finding of no less than five cases of the same coinciding positions4 ,the importance of the identification here made of an arctic canal with a previous rift in the polar cap has led me to make a list of the canals thus identified at this opposition4 ,,visible ,,as ,a ,,rift ,,visible ,,as ,a ,,canal ---------------------------------------- -------------------------- ,hypanis ,january #a and ,february #d ,april #ah 7871 ,may #bj1 #bb1 #bg1 ,june #d1 #e1 #f1 #g1 #h1 #be ,hippalus ,january #ai and ,february #d ,april #ah1 ,may #bg ,rhombites ,february #d ,may #bg ,python ,february #bj ,march #ca ,zygatis ,january #ah1 #ai ,may #g1 ,june #c to #h ,if it be asked why these canals do not appear recorded at the ,march presentation as either the one phenomenon or the other1 the answer is twofold4 ,first1 because they showed as shadings lost amidst a shaded mass2 and1 secondly1 the observations at several oppositions indicate a great amount of haze over the region at that season of the ,martian year4 ,we may now go back to the very first rift1 that of #ahig4 ,the ,martian season grew later with each succeeding opposition1 and it so chanced1 abetted by this fact1 that the delaying snow was never seen covering that part of the planet again and so1 of course1 not the rift4 ,the ,martian summer in those high latitudes came on1 and with it brought the great arctic canal1 the ,jaxartes1 into conspicuousness4 ,the canal in consequence had been observed for some time before it proclaimed itself the apotheosis of a rift and that of the first and most important rift of all4 ,comparison of position1 however1 entirely confirmed the conjecture and added another and the most striking of all to the list4 ,these six canals1 on the whole the largest which run into the northern cap1 have thus a dual character4 ,starting originally as rifts1 they later come out unmistakably as canals4 ,so that we may say in general that the two phenomena are different seasonal states of the same thing4 ,this instantly explains the rifts1 the origin of which we found of so difficult1 not to say impossible1 interpretation before in these pages1 and incidentally it confirms what we deduced on other grounds as the character of the canals2 to wit1 strips of vegetation4 ,for if the cap covered desert and fertility alike1 it is precisely over the latter that it would first melt4 ,vegetation has the property of melting snow4 ,the metabolism of the plant1 like that of the animal1 though in a less degree1 generates caloric4 ,a living animal is warm1 even the so-called cold-blooded ones1 in some sort1 and a growing plant is too4 ,the chemic processes concerned give off heat1 though in such small quantities that we are often not aware of it4 ,while the plant lies dormant it stays cold1 but the moment its sap begins to run under the rays of the spring sun it rises in temperature above its winter surroundings4 ,all it needs to this awakening is sun and water1 and both it gets in its place in the polar cap after the passing of the vernal equinox4 ,the time1 therefore1 is suitable1 for it is not till after that equinox is passed that any of the above phenomena occur4 ,in consequence the snow about it melts and the plants themselves show as dark rifts splitting the cap4 ,this quite unexpected identity of two seemingly diverse phenomena1 and the unsolicited support its only explanation lends to the general theory1 is an instance of what is constantly occurring as observation of the planet is pushed farther and farther4 ,facts every little while arise which prove to fit into place in the scheme when neither the facts nor their fitness could have been foreseen4 ,,chapter ,,xxvii ,,oases3 ,,kinematic ,subject to change also are the oases2 and in the same manner apparently as the canals4 ,they grow less evident at a like season of the ,martian year4 ,they do this seemingly by decreasing in size4 ,whereas in the full expanse of their maturity they show as round spots of appreciable diameter1 as the season wanes they contract to the smallest discernible of dots4 ,all but the kernel1 as it were1 fades out1 and even this may disappear from sight4 ,the ,phnix ,lake in its summer time is a very dark circular spot1 small indeed yet of definite extension2 in its winter it shrinks to a pin point1 and is often not visible at all4 ,sometimes the husk apparently persists1 a ghostlike reminiscence of what it was1 with the kernel showing dark-pointed in its centre4 ,thus the ,lucus ,lunae appeared at the opposition of #aije4 ,a faint wash betokened the presence of the ,lucus1 through which now and again a black pin-point pierced4 ,in this visible decrease of size we get a revelation as to what takes place impossible in the case of the canals1 the tenuous character of which precludes more than inference as to the process4 ,like the canals1 latitude1 together with the suitable season of the planet's year1 are the determining factors in their development4 ,in what corresponded to our ,july of the northern hemisphere the oases in the sub-arctic and north temperate zones were conspicuous2 black spots that showed in profusion along the parallels of #dj1 #ej1 and #fj north4 ,at the same time the equatorial ones1 those along the ,eumenides-,orcus1 which had been most evident in #ahid1 hardly came out4 ,it had been their time then as it was that of the others now4 ,the law of development is not so simple as on the earth1 depending1 like that of the canals1 not only upon the return of the sun1 but upon the advent of the water let loose from about the polar caps4 ,thus the equatorial oases are subject to two seasonal quickenings1 one from the north1 the other from the south4 ,in regard to their method of evolution or devolution a most curious observation happened to me in #aijc4 ,usually the oases are of solid tone throughout2 equally sombre from centre to circumference4 ,but in this case such uniform complexion found exception4 ,on ,march #a1 #aijc1 the ,ascraeus ,lucus came out strangely differentiated1 a dark rim inclosing a less dark kernel4 ,the sight was odd enough to command comment in the shape of a sketch which accompanied the note1 and the further remark that other spots had similarly that year affected the like look4 ,that the effect was optical did not seem to me the case4 ,other spots at other times showed nothing of the sort4 ,if it was due to objective cause it gathers circumstance from what was then the ,martian time of year4 ,for the season was such that the spot should then have been in process of waning2 and the effect would indicate that in so doing the tone of the centre went first1 that of the circumference fading last4 ,this would be in accordance with a growth proceeding outward and a decay that followed in its steps4 ,when to this we add the look of the oases at the antithetic season1--often a faint shading only1 with or without a darker pin-point at its core1--we are led to the belief that the area of the oasis is unchangeable and that its growth means a deepening of tint4 ,so far1 then1 as it is possible to particularize them1 the oases develop from a small nucleus1 perhaps twenty miles in diameter1 perhaps less1 and from this spread radially till they attain a width of seventy-five or one hundred miles4 ,if the oasis be associated with a double canal1 this maximum width exactly fits the space between the twin lines4 ,even when no double enters the oasis1 the size is about the same4 ,this size attained1 they hold it for some months4 ,then they proceed to fade out to their initial nucleus1 and after a sufficient rest the process starts over again4 ,with the carets something of the same sort seems to take place--if we may consider as betokening a general law the fact that in #ahid the carets at the mouths of the ,phison and ,euphrates developed before their affiliated canals4 ,but about them much less is yet known1 and we must be content to say that the observations of #aije made at the opposite season of the canal's year seem to bear this out4 ,,part ,,iv ,,explanation ,,chapter ,,xxviii ,,constitution ,,of ,,the ,,canals ,,and ,,oases ,as rational science does not rest content with raw results1 it now becomes obligatory1 by marshaling the facts to suitable discussion1 to seek to find out what they mean4 ,now1 so soon as we scan these phenomena for some self-interpretation1 we perceive one characteristic of the lines which at once appears to direct us to their nature and justifies itself as a signpost with increasing certainty as we read on4 ,this trait is the very simple yet most significant one of showing intrinsic change3 the lines alter in visibility with time4 ,this primary proclivity we do not even need the cartouches to establish4 ,that the lines change is palpable to any one who will watch them long enough4 ,schiaparelli was struck by the fact early in his study of the planet1 and it forces itself on the notice of any careful observer who compares his own observations with one another at intervals4 ,but though the cartouches are not needed to a first revelation of mutability1 they serve to certify and precise it to much further information on the subject4 ,for1 that these changes are not extrinsic1 that is1 are not caused by varying definition1 distance1 or illumination1 they make patent even to those who have never seen the things themselves by disclosing respective differences of behavior in lines similarly circumstanced optically4 ,the change is therefore intrinsic1 and the question arises to what can such intrinsic change be due4 ,in searching for cause1 attention is at once attracted by another series of transmutations that manifests itself upon the disk1 in the orderly melting of the polar caps4 ,for the existence of the two sets of metamorphoses suggests the possibility of a connection between them4 ,the inference is strengthened when we note that not only are both periodic1 but that furthermore the period of the two is the same4 ,each polar cap runs through its gamut of change in a ,martian year2 the canals also complete their cycle of growth and decay in a ,martian twelvemonth4 ,the only difference between the two is that each polar cap has but one maximum and one minimum in the course of this time1 while most of the canals have two of each1 though the maxima are not alike nor the minima either4 ,not only is the period of the two series of changes the same1 but the one follows the other4 ,for the development of the canals does not begin till the melting of the polar cap is well under way4 ,now1 as the polar cap disintegrates it gives rise1 as we have seen1 to a dark belt of blue-green which fringes its outer edge and retreats with it as it shrinks4 ,this tells1 directly or indirectly1 of a product let loose4 ,after this belt has been formed the canals nearest to it proceed to darken1 then those a little farther off follow suit1 and so the wave of visibility rolls in regular routine down the disk4 ,here1 then1 at the outset we have a chronic connection between the two phenomena1 the disintegration of the cap and the integration of the canals4 ,of water we saw that the caps were undoubtedly composed1 and to water1 then1 let loose by the melting of the cap1 we may inferably ascribe the thaumaturgy in the development of the canals4 ,but it is not necessary to suppose that this is done directly4 ,that the increased visibility of the canals can be due to a bodily transference of water seems doubtful1 if for no other reason than the delay in the action4 ,considerable time intervenes between the disappearance of the cap and the appearance of the canals1 except in the case of such as have been covered by it4 ,transformation consequent upon transference1 however1 would account for hesitancy4 ,a quickening to vegetal growth would produce the counterpart of what we see4 ,if1 set free from the winter locking up1 the water accumulated in the cap then percolated equatorward1 starting vegetation in its course1 this would cause the increased visibility of the canals and at the same time explain the seeming delay1 by allowing for the time necessary for this vegetation to sprout4 ,this is certainly the most satisfactory explanation of the phenomena4 ,thus started1 the vegetal quickening would pass down the planet's surface and give rise to what we mark as seasonal change4 ,but1 though in one sense of seasonal character1 a little consideration will show that it would be quite unlike the seasonal change which we know on earth4 ,could we see our earth from some standpoint in space1 we should mark1 with the advent of spring1 a wave of verdure sweep over its face4 ,if freedom from cloud permitted of an unimpeded view1 this flush of waking from winter's sleep would be quite evident and could be seen to spread4 ,starting from the equator so soon as the sun turned north1 it1 too1 would travel northward1 and1 distancing the sun1 arrive by midsummer well into the arctic zone4 ,here1 then1 we should note1 much as we note it on ,mars1 a tint of blue-green superpose itself successively upon the ochre ground2 but the mundane and the ,martian vegetal awakening would differ in one fundamental respect2 the earthly wave would be seen to travel from equator to pole1 while the ,arian travels from pole to equator4 ,though clearly seasonal in character1 both of them1 the transformations would be opposite in action4 ,some other cause1 then1 must be at work from what we are familiar with on earth4 ,this other cause is the presence or absence of moisture4 ,two factors are necessary to the begetting of vegetal life1 the raw material and the reacting agent4 ,oxygen1 nitrogen1 water1 and a few salts make up the first desideratum1 the sun supplies the second4 ,unless both be present1 the quickening to life never comes4 ,now1 the one may be there and the other not1 or the other there and the one not4 ,on earth the material including water is1 except in certain destitute localities1 always present2 the sun it is that periodically withdraws4 ,observant upon the return of the sun is therefore the annual recurrence of vegetal growth4 ,on ,mars1 on the contrary1 water is lacking4 ,this we now know conclusively from other phenomena the disk presents which have no connection with the present investigation and are1 therefore1 unprejudiced witnesses to the fact4 ,no permanent bodies of water stud its surface4 ,that the so-called seas are traversed by dark lines permanent in place is one of several proofs of this4 ,the only surface water the planet knows comes from the melting of its polar caps4 ,vegetation cannot start until this water reaches it4 ,consequently1 though the sun be ready1 vegetation must wait upon the coming of the water1 and starting from near the pole follow the frugal flood equatorward4 ,illustration3 ,,phenology ,,curves--,,earth4 99 ,dead ,point of ,vegetation4 7,from paper in ,proc4 ,amer4 ,phil4 ,soc41 by ,percival ,lowell47 ,illustration3 ,,phenology ,,curves--,,mars4 99 ,dead ,point of ,vegetation4 7,from paper in ,proc4 ,amer4 ,phil4 ,soc41 by ,percival ,lowell47 ,now1 such contrariety of progression to what we should observe in the case of the earth could we view it from afar is exactly what the curves of visibility of the canals exhibit4 ,timed primarily1 not to the return of the sun but to the advent of the water1 vegetal quickening there follows1 not the former up the latitudes but the latter down the disk4 ,for better understanding1 the two curves of phenological quickening1 the mundane and the ,martian1 are shown in the diagrams4 ,the plates represent the surfaces of the two planets1 that of the earth being shown upside down with south at the top so as to agree with the telescopic depiction of the topography of ,mars4 ,the stars mark the epoch of the dead-point of vegetation at successive latitudes2 the time increasing toward the right4 ,the curves1 it will be noticed1 are bowed in opposite ways4 ,the bowed effect is due in part to ,mercator's projection2 in part it may represent a real decrease in speed with time4 ,but what is strikingly noticeable is the opposite character of the advance to the right1 the one curve running up the disk1 the other down it4 ,this shows that the development of vegetation proceeded in opposite directions over the surface4 ,thus is the opposed action upon the two planets accounted for1 and we are led to the conclusion that the canals are strips of vegetation fed by water from the polar caps1 and that the floral seasons there as affecting the canals are conditioned1 not as they would be with us1 directly upon the return of the sun1 but indirectly so through its direct effect upon the polar snows4 ,once adventured on the idea of vegetation1 we find that it explains much more than the time taken by the wave of canal-development down the disk4 ,it accounts at once for the behavior of the canals in the three northern zones3 the polar1 arctic1 and sub-arctic4 ,the mean cartouches of these three zones dip down at their latter end instead of rising there1 as is the case with the cartouches of the mean canals farther south4 ,this dip denotes that the most northern canals were waning already by the middle of their ,august1 though the others showed no such tendency2 while the date of the deposition of the frost in these northern latitudes shows that they were started upon their course toward extinction before the snow itself had covered them4 ,in other words1 they were not obliterated but snuffed out4 ,that their decline was thus preparatory to the coming of the first snowfall or frost-fall1 sufficiently severe to whiten the ground so that it did not melt the next day1 is suggestive of their constitution4 ,it is clear that they were not abruptly cut off by the frost1 but were timed by nature to such extinction4 ,vegetation would behave in just this way1 since evolution would accommodate the career of a plant to its environment4 ,the first question to present itself chronologically in the canals' annual history is connected with the size of the cap4 ,unfortunately for the simplicity of the phenomena1 the cap is not an extensionless source of flow1 but an extended surface melting from the outer edge in4 ,it would seem1 therefore1 that water liberated from the outer parts should have an effect before the main body of it were ready to begin its general march down the disk4 ,there should be1 one would think1 at least a partial action1 locally1 before the main action got under way4 ,now1 there are certain canals that show cartouches increasing apparently from the time observations began1 and the most pronounced is the ,jaxartes1 which lies of all the canals observed the farthest north4 ,now1 the cartouches were founded on canals quickened from the north polar cap4 ,the farther north the canal1 therefore1 the greater the likelihood of its showing the phenomena4 ,that we note such canals is therefore not only not subversive1 but actually corroboratory1 of the law it seems at first to shake4 ,that all the canals of these zones do not show a like cartouche-profile is not necessary1 a part of them being dependent1 not upon the earlier1 but upon the later liberated flow1 and thus partaking in the general law1 which grows uniform lower down the latitudes4 ,as the action from one polar cap proceeds1 not only down to the equator1 but across it into the planet's other hemisphere1 it appears that much1 at least1 of the surface of ,mars has two seasons of vegetal growth1 the one quickened of the north polar cap1 the other of the southern4 ,how far the polar spheres of action overlap it is not possible at present to affirm1 as the canals at this opposition were only visible to #ce south latitude4 ,that the north polar quickening goes down so far is vouched for1 and it is probable from other observed phenomena that it goes farther4 ,the alternate semi-annual quickening also discloses itself directly in the cartouches2 the previous semestral growth from the south polar cap actually showing in them before the impulse from the north began4 ,the slow falling of their curves to the minimum preceding their later rise is nothing less than the dying out of the effect started six months before from the south4 ,the gentler gradient of their fall proclaims a gradual lapse1 just as the subsequent sharper rise points to the advent of a fresh impulse4 ,and this deduction seems to be borne out by another circumstance4 ,there is some evidence of decrease in the pre-minimal gradient southward4 ,this is telling testimony to the source whence the impulse came4 ,for if it originated at the south and traveled northward1 the southern canals would be the first to be affected and the first to die out1 and thus show a longer dead season1 exhibited in the cartouches as a more level stretch4 ,lastly1 the explanation of the canals as threads of vegetation fays in with the one which has been found to meet the requirements of the blue-green areas2 while the fact that they prove to develop as they do1 reversely to what would take place on earth1 is exactly what all we have latterly learnt about the surface conditions of the planet would lead us to expect4 ,from what has just been said we see that the latest observations at ,flagstaff confirm the earlier ones1 and1 what is especially corroborative1 they do so along another line4 ,the former were chiefly static1 the latter kinematic4 ,in other words1 the behavior of the canals in action bears out the testimony of their appearance at rest4 ,,chapter ,,xxix ,,life ,study of the fundamental features of ,martian topography has disclosed1 as we have seen1 the existence of vegetation on the planet as the only rational explanation of the dark markings there1 considered not simply on the score of their appearance momentarily1 but judged by the changes that appearance undergoes at successive seasons of the ,martian year4 ,thus we are assured that plant life exists on the planet4 ,we are made aware of the fact in more ways than one1 but most unanswerably for that trait to which vegetation owes its very name1--its periodic quickening to life4 ,thus the characteristic which has seemed here most distinctive of this phase of the organic1 so that man even christened it in accordance1 has proved equally telltale there4 ,important as a conclusion this is no less pregnant as a premise4 ,for the assurance that plant life exists on ,mars leads to a further step in extramundane acquaintance of far-reaching import4 ,it introduces us at once to the probability of life there of a higher and more immediately appealing kind1 not with the vagueness of general analogy1 but with the definiteness of specific deduction4 ,for the presence of a flora is itself ground for suspecting a fauna4 ,of a bond connecting the two we get our first hint the moment we look inquiringly into the world about us1 that of our own earth4 ,common experience witnesses to a coexistence which grows curious and compelling as we consider it4 ,for it is not confined to life of any special order1 but extends through the whole range of organisms of both kinds from the lowest to the highest4 ,alg and monera1 orchid and mammal1 occur side by side and with a certain considerate poverty or richness1 as the case may be4 ,luxuriance in the one is matched by abundance in the other2 while a scanty flora means a poor fauna4 ,this of which we have been aware in regions round about us from childhood grows in universality as we explore4 ,wherever man penetrates out of his proper sphere he finds the same dual possession of the land or the sea1 and a similar curtailing or expanding of both tenantries together4 ,no mountain top so cold but that if it grow plants1 it supports insects and animals1 too1 after its kind2 no desert so arid but that creeping things find it as possible a habitat as life that does not stir4 ,even in almost boiling geysers animalcula and conferv share and share alike4 ,only where extreme conditions preclude the one do they equally debar the other4 ,proceeding now from the fact to its factors we perceive reasons for this tenure in common of the land by the vegetal and animal kingdoms4 ,examination proves the two great divisions of the organic to be inextricably connected4 ,it strikes our notice first in the relation of plants to animals4 ,it is of everyday notoriety that animals eat plants1 though it is less universally understood that in the ultimate they exist on nothing else4 ,plants furnish the food of animals2 not as a matter of partial preference but of fundamental necessity4 ,for the plant is the indispensable intermediary in the process of metabolism4 ,without plants animals would soon cease to exist1 since they are unable to manufacture their own plasm out of the raw material offered by inorganic nature4 ,they must make it out of the already prepared plasm of plants or out of other animals who have made it from plants4 ,so that in the end it all comes back to plant production4 ,the plant is able to build its plasm out of chemical substances2 the animal cannot1 except in the case of the nitro-bacteria1 begin thus at the lowest rung of the alimentary ladder4 ,but the converse of this dependence is also largely true4 ,plants are beholden to animals for processes that in return make their own life possible4 ,the latter minister to the former with unconscious service all the time1 and with no more arrogant independence than do our domestics generally nowadays4 ,the inconspicuous earthworm is the fieldhand of nature's crops1 who gets his own living by making theirs4 ,without this day and night laborer the soil for want of stirring had remained less capable of grass4 ,above ground it is the same story4 ,deprived of the ministrations of insects many kinds of plants would incontinently perish4 ,by the solicited visits of bees and other hymenoptera--what generically may be classed by the layman as flutter-bys--is the plant's propagation made possible4 ,peculiarly well named1 indeed1 are the hymenoptera1 seeing that they are the great matrimonial go-betweens1 carrying pollen from one individual to another and thus uniting what otherwise could not meet4 ,spectacular as this widespread commerce is1 it forms but portion of the daily drama in which animals and plants alike take part4 ,from forthright bargainings of honey for help1 we pass to less direct but no less effective alliance where plants are beholden to animals for life by the killing of their enemies or the weeding-out of their competitors1 and from this to generic furtherance where the interdependence becomes broadcast4 ,in the matter of metabolism the advantage is not all upon one side4 ,in the katabolic process of that which each discards are the two classes of life mutually complimentary1--the waste of the one being the want of the other1--carbonic acid gas being given off by the animal1 oxygen by the plant4 ,in biologic economy it is daily more demonstrable that both are necessary constituents to an advancing whole1 and that each pays for what it gets by what it gives in return4 ,that they are thus ancillary as well as coexistent today leads us to confront for them a community of origin in the past2 and further study confirms the inference4 ,both paleontology and entomology1 or the science of the aged and the science of the young1 prove such ancestry to be a fact4 ,by going back from the present into the past1 or1 what amounts to substantially the same thing1 by descending in the scale of life to the lowest known forms of organism1 we find proof of concomitance1 cogent because congenital4 ,at the time when inorganic chemical compounds first passed by evolution into organic ones1 the change was of so general a character that even such tardy representatives of it as survive today tax erudition to tell to which of the two great kingdoms they belong1 the vegetal or the animal4 ,simplest and most primitive of known organisms are the chromacea1 unnucleated single cells as ,haeckel has shown1 and next to them in order come many of the bacteria1 also of simple unnucleated plasm4 ,so little do the majority of the bacteria differ morphologically from the chromacea1 that on the score of structure the two are not to be catalogued apart4 ,both are as elemental as anything well can be1 which only their diet serves to divide4 ,each is an organism without organs1 thus belying the dictionary definition of both animals and plants4 ,etymologically they are not organic yet manifestly are alive1 and only in their action are unlike4 ,the chromacea are plasm-forming beings1 and therefore they are plants2 the bacteria are plasm-eating beings1 and so are animals4 ,even this distinction is not always preserved4 ,as ,haeckel tells us3 8the nitro-bacteria which dwell in the earth having the vegetal property of converting ammonia by oxidation into nitrous acid and this into nitric acid1 using as their source of carbon the carbonic acid gas of the atmosphere4 ,they feed1 like the chromacea1 on simple inorganic compounds40 ,here1 then1 we have1 close to the threshold of organic life1 unorganized organisms1 roughly speaking coeval and differing in a sense but little1 either of them1 from inorganic crystals2 and yet the one is an animal1 the other a plant4 ,progenitors of the two great divisions of life1 they were themselves concomitantly evolved1 either side by side or as offshoots both of a common stock4 ,now1 if the ancestors of the two great organic kingdoms were thus simultaneously produced here1 we are warranted in believing that they would similarly be produced elsewhere1 given conditions suitably alike4 ,in consequence1 if we detect the presence of the one1 we already have an argument for inferring the other4 ,not to complete our syllogism would be to flaunt a lack of logic in nature's face4 ,rationally viewed1 then1 the general problem of life in other worlds reduces itself to a question of conditions4 ,since certain physical results follow inevitably upon certain physical premises1 if we can assure ourselves of the proper premises we may look to nature for their conclusion4 ,a priori1 then1 the possibility of life becomes one of habitat4 ,if the environment be suitable life will ensue4 ,what makes for such a mediary milieu is1 like most cosmic processes1 in its fundamentals of interesting simplicity2 for the production of a proper nidus depends primarily upon the mere size of the body parentally concerned4 ,if a planet be big enough it will inevitably bring forth life1 because of conditions suitable to its generating2 if too small it will remain sterile to the end of time4 ,that size should be the determining factor whether a planet shall be fecund or barren may seem at first thought strange4 ,yet that it is so admits of no rational doubt4 ,all that we see of bodies about us shows its truth1 and what we have learnt of cosmic process enables us in some sort to discern why4 ,in order for evolution1 such as we mark it upon the earth1 to be possible1 the parent body must have been at one time at a high temperature1 since only under great heat can the primal processes occur4 ,but for this generation of caloric the aggregate mass of the particles1 the falling together of which makes the planet1 and their stoppage its internal heat1 must be large4 ,the sun's rays alone are insufficient to cause the necessary temperature2 the heat must come from within1 though it be helped from without4 ,even here the action is abetted by a large body4 ,for a planet to entrap the sun's rays or even to preserve its own internal warmth1 an atmosphere is needed1 and it takes a large body to retain an atmospheric covering sufficiently long4 ,yet without it not only would there be no suitable state1 but no medium in which organic or even inorganic reactions could go on4 ,lastly1 water1 the essential nidus for the organism's early stages1 has its presence similarly conditioned4 ,for this1 like the atmosphere1 would from a small body speedily vanish away4 ,thus the planet itself is the life-producing body1 although the sun furthers the process when once begun4 ,that the needed substances are planetarily present1 what we know of the distribution of matter astronomically sufficiently attests4 ,what we find in meteorites shows that the catastrophe which preceded our present solar system's birth scattered its elemental constituents throughout its domain1 and thus when they came to be gathered up again into planets that these must have been materially the same4 ,the manner1 not the matter1 then1 is alone that about which we are concerned4 ,now1 if the mass of matter gravitating together to form a planet be sufficient to produce the proper inorganic conditions1 the organic must follow as a matter of course4 ,that the organic springs from the inorganic is not only shown by what has taken place on earth1 but is the necessary logical deduction from its decay back into the inorganic again4 ,as ,ngeli admirably observes3 8,the origin of the organic from the inorganic is1 in the first place1 not a question of experience and experiment1 but a fact deduced from the law of the constancy of matter and force4 ,if all things in the material world are causally related1 if all phenomena proceed on natural principles1 organisms which are formed of and decay into the same matter must have been derived originally from inorganic compounds40 ,the original oneness of the two1 the fact that the organic sprang from the inorganic1 is shown by the cousinly closeness of the lowest organic with the highest inorganic substances4 ,the monera are suggestive of crystals in their uniformity of structure4 ,both are homogeneous or approximately so4 ,again1 both grow by taking from what they come in contact with that which they find suitable and so add to their body by homogeneous accretion4 ,finally1 when grown too large for single life1 they part into similar crystals or split into identical cells4 ,the difference between the division of the crystal and the fission of the cell is small in kind2 much less than that later differentiation in genesis into parthenogenesis and sexual reproduction4 ,yet here we unhesitatingly trace an assured relationship4 ,it were straining at a gnat to swallow a camel to doubt it in the other4 ,just as the two behave analogically alike in their own action1 so do they observe a like attitude toward nature4 ,they thus point to their common origin4 ,the monera are resemblant of chemical compounds in their superiority to external influences4 ,to outward conditions of temperature and humidity the chromacea are much as sticks and stones4 ,some species may remain for long frozen in ice1 ,haeckel observes1 and yet wake to activity so soon as it thaws4 ,others may be completely desiccated1 and then resume their life when put in water after a lapse of several years4 ,thus both in their deathlike lives and in their living immortality the chromacea are close to inorganic things4 ,from preference1 however1 these lowest forms of life affect what to us would be unbearable temperatures4 ,many of the chromacea live in hot springs at temperatures of #abc to #agf ,fahrenheit1 in which no other1 that is1 no higher1 organism can dwell4 ,this choice of habitat is in line with the other details of their evolutionary career4 ,for it1 too1 is in keeping with the conditions of crystalline growth1 halfway as it were on the road to them2 the forming of crystals beginning at a temperature higher still4 ,and we perceive from it that the passing of the inorganic into the organic is brought about by a lowering of the temperature of the parent planet4 ,this again1 is in line with the evolution of chemical complexity4 ,let the heat become less1 and higher and higher chemical compounds1 finally the organic ones1 become possible4 ,that evolution is nothing else than such a gradually increasing chemical synthesis is forced on one by study of the facts4 ,once started1 life1 as paleontology shows1 develops along both the floral and the faunal lines side by side1 taking on complexity with time4 ,it begins so soon as secular cooling has condensed water vapor to its liquid state2 chromacea and conferv coming into being high up toward the boiling-point4 ,then1 with lowering temperature come the seaweeds and the rhizopods1 then the land plants and the lunged vertebrates4 ,hand in hand the fauna and flora climb to more intricate perfecting1 life rising as temperature lowers4 ,we perceive then that1 considered a priori1 the possibility of life on a planet is merely a question of the planet's size2 and then pursuantly that the character of that life is a matter of the planet's age4 ,but age again is a question of size4 ,for the smaller its mass the quicker the body cools1 and with a planet1 growing cold means growing old4 ,within the bounds that make life possible1 the smaller the body the quicker it ages and the more advanced its denizens must be4 ,just how far the advance goes we may not assert dogmatically in a given case1 since not relative age alone but absolute time as well is concerned in it4 ,it may be that nature's processes cannot be hurried1 and that for want of time development may in part be missed4 ,but from general considerations the limit of the time needed seems well within most planetary careers4 ,now1 the aspect of the surface of ,mars shows that both these conditions have been fulfilled4 ,mars is large enough to have begotten vegetation and small enough to be already old4 ,all that we know of the physical state of the planet points to the possibility of both vegetal and animal life existing there1 and furthermore1 that this life should be of a relatively high order is possible4 ,nothing contradicts this1 and the observations of the last ten years have rendered the conclusion then advanced only the more conclusive4 ,even the evidence of the past state of the planet confirms that given by its present one4 ,that with us life came out of the seas finds its possible parallel in the fact that seas seem once to have existed there1 leaving their mark discernible to-day4 ,life1 then1 had there as here the wherewith to begin4 ,that we find air and water in both shows that it had the means to continue once begun4 ,that it then ran a like course is further witnessed by what we now detect4 ,the necessary premises1 then1 are there4 ,more than this4 ,one half of the conclusion1 vegetal life1 gives evidence of itself4 ,,chapter ,,xxx ,,evidence ,of the existence of animal life upon a far planet any evidence must1 of necessity1 assume a different guise from what its flora would present4 ,plant life should be1 as on ,mars we perceive it is1 recognizable as part and parcel of the main features of the planet's face4 ,in no such forthright manner could we expect an animal revelation4 ,the sort of testimony which would render the one patent would leave the other obstinately hid4 ,so long as animate life was in the lowest sense animal1 it would not be seen at all1 though it were as widespread as the vegetal life all about it4 ,reason for this lies in their receptive character4 ,plants are fixtures2 where they start they stay2 while from the nature of their food1 derived directly from the soil and from the air1 and conditioned chiefly by warmth and moisture1 like forms inhabit large areas and by their massed effect make far impression4 ,with animals it is otherwise4 ,they feed by forage1 from beetle to buffalo1 roaming the land for sustenance4 ,thus1 both for paucity of number and from not abiding in one stay they must escape notice at a distance such that as individuals they fail to show2 to say nothing of the fact that the flora usually overtop the fauna1 and so help to hide the latter while appearing itself distinct4 ,any far view of our earth gives instance of this4 ,seen from some panoramic height1 forest and moorland lie patently outspread to view1 yet imagination is taxed to believe them tenanted at all4 ,unless man have marred the landscape not a sign appears of any living thing4 ,one must be near indeed to note even such unusual sights as a herd of buffalo in the plains or those immense flights of pigeons1 that in former years occurred like clouds darkening the air4 ,from the standpoint of another planet1 through any such direct showing animal existence would still remain unknown4 ,not until the creatures had reached a certain phase in evolution would their presence become perceptible2 and not then directly1 but by the results such presence brought to pass4 ,occupancy would be first evidenced by its imprint on the land2 discernible thus initially not so much by the bodily as by the mind's eye4 ,for not till the animal had learnt to dominate nature and fashion it to his needs and ends would his existence betray itself4 ,by the transformation he wrought in the landscape would he be known4 ,it is thus we should make our own far acquaintance2 and by the disarrangement of nature first have inkling of man4 ,that it is thus we should betray ourselves1 a consideration of man's history will show4 ,while he still remained of savage simplicity1 a mere child of nature1 he might come and go unmarked by an outsider1 but so soon as he started in to possess the earth his handicraft would reveal him4 ,from the moment he bethought him to till the ground1 he entered upon a course of world-subjugation of which we cannot foresee the end2 but he has already advanced far enough to give us an idea of the process4 ,it began with agriculture4 ,deforestation with its subsequent quartering of crops signalized his acquisition of real estate4 ,his impress at first was sporadic and irregular1 and in so far followed that of nature itself2 but as it advanced it took on a methodism of plan4 ,husbandry begot thrift1 and augmented wants demanded an increasing return for toil2 and to this desirable end systematization became a necessity4 ,at the same time gregariousness grew and still further emphasized the need for economy of space and time4 ,in part unconsciously1 man learnt the laws that govern the expenditure of force and more and more consciously applied them4 ,geometry1 unloosed of ,euclid1 became a part of everyday life as insidiously as ,m4 ,jourdain found that he had been talking prose4 ,regularity rules to-day1 to the lament of art4 ,the railroad is straighter than the turnpike1 as that is straighter than the trail4 ,communication is now too urgent in its demands to know anything but law and take other than the shortest path to its destination4 ,tillage has undergone a like rectification4 ,to one used to the patchwork quilting of the crops in older lands the methodical rectangles of the farms of the ,great ,west are painfully exact4 ,yet it is more than probable that these material manifestations would be the first signs of intelligence to one considering the earth from far4 ,our towns would in all likelihood constitute the next2 and1 lastly1 the great arteries of travel that minister to their wants4 ,their scale1 too1 would render them the first objects to be observed4 ,farming as now practiced in ,kansas or ,dakota gives it a certain cosmical concern2 fields for miles turning in hue with the rhythm of the drilled should impress an eye1 if armed with our appliances1 many millions of miles away4 ,even now we should know ourselves cosmically by our geometrical designs4 ,to interplanetary understanding it is this quality that would speak4 ,still more so will it tell as time goes on4 ,as yet we are but at the beginning of our subjugation of the globe4 ,we have hardly explored it all1 still less occupied it4 ,when we do so1 and space shall have become enhancedly precious1 directness of purpose with economy of result will have partitioned so regularly the surface of the earth as to impart to it an artificiality of appearance1 and it becomes one vast cordinated expanse subservient entirely to the wants of its possessors4 ,centres of population and lines of communication1 with tillage carried on in the most economic way2 to this it must come in the end4 ,nor is this outcome in any sense a circumstance accidental to the earth2 it is an inevitable phase in the evolution of organisms4 ,as the organism develops brain it is able to circumvent the adversities of condition2 and by overcoming more pronounced inhospitality of environment not only to survive but spread4 ,evidence of this thought will be stamped more and more visibly upon the face of its habitat4 ,on earth1 for all our pride of intellect1 we have not yet progressed very far from the lowly animal state that leaves no records of itself4 ,it is only in the last two centuries that our self-registration upon our surroundings has been marked4 ,with another planet the like course must in all probability be pursued1 and the older the life relatively to its habitat the more its signs of occupation should show4 ,intelligence on other worlds could then only make its presence known by such material revelation1 and the sign-manuals of itself would appear more artificial in look as that life was high in rank4 ,given the certainty of plant-life1 such markings are what one would look to find4 ,criticism which refuses to credit detail of the sort because too bizarre to be true writes itself down as unacquainted with the character of the problem4 ,for it is precisely such detail which should show if any evidence at all were forthcoming4 ,if1 now1 we turn our inquiry to ,mars1 we shall be fairly startled at what its disk discloses4 ,for we find ourselves confronted in the canals and oases by precisely the appearances a priori reasoning proves should show were the planet inhabited4 ,our abstract prognostications have taken concrete form4 ,here in these rectilineal lines and roundish spots we have spread out our centres of effort and our lines of communication4 ,for the oases are clearly ganglia to which the canals play the part of nerves4 ,the strange geometricism which proves inexplicable on any other hypothesis now shows itself of the essence of the solution4 ,the appearance of artificiality cast up at the phenomena in disproof vindicates itself as the vital point in the whole matter4 ,like the cachet of an architect1 it is the thing about the building that established the authorship4 ,though the ,earth and ,mars agree in being planets1 they differ constitutionally in several important respects4 ,even to us the curious network that enshrouds the ,martian disk suggests handicraft2 it implies it much more when considered from a ,martian standpoint4 ,,chapter ,,xxxi ,,the ,,husbanding ,,of ,,water ,that the canals and oases are of artificial origin is thus suggested by their very look2 when we come to go further and inquire into what may be their office in the planet's economy1 we find that the idea in addition to its general probability now acquires particular support4 ,for this we are indebted in part to study of their static aspect1 but chiefly to what has been learnt of their kinematic action4 ,dearth of water is the key to their character4 ,water is very scarce on the planet4 ,we know this by the absence of any bodies of it of any size upon the surface4 ,so far as we can see the only available water is what comes from the semi-annual melting at one or the other cap of the snow accumulated there during the previous winter4 ,beyond this there is none except for what may be present in the air4 ,now1 water is absolutely essential to all forms of life2 no organisms can exist without it4 ,but as a planet ages1 it loses its oceans as has before been explained1 and gradually its whole water supply4 ,life upon its surface is confronted by a growing scarcity of this essential to existence4 ,for its fauna to survive it must utilize all it can get4 ,to this end it would be obliged to put forth its chief endeavors1 and the outcome of such work would result in a deformation of the disk indicative of its presence4 ,lines of communication for water purposes1 between the polar caps1 on the one hand1 and the centres of population1 on the other1 would be the artificial markings we should expect to perceive4 ,now1 it is not a little startling that the semblance of just such signs of intelligent interference with nature is what we discern on the face of ,mars1--in the canals and oases4 ,so dominant in its mien is the pencil-like directness of the canals as to be the trait that primarily strikes an unprejudiced observer who beholds this astounding system of lines under favorable definition for the first time1 and its impressiveness only grows on him with study of the phenomena4 ,that they suggested rule and compass1 ,schiaparelli said of them long ago1 without committing himself as to what they were4 ,in perception the great observer was1 as usual1 quite right2 and the better they are seen the more they justify the statement4 ,punctilious in their precision1 they outdo in method all attempts of freehand drawing to copy them4 ,often has the writer tried to represent the regularity he saw1 only to draw and redraw his lines in vain4 ,nothing short of ruling them could have reproduced what the telescope revealed4 ,strange as their depiction may look in the drawings1 the originals look stranger still4 ,indeed1 that they should look unnatural when properly depicted is not unnatural if they are so in fact4 ,for it is the geodetic precision which the lines exhibit that instantly stamps them to consciousness as artificial4 ,the inference is so forthright as to be shared by those who have not seen them to the extent of instant denial of their objectivity4 ,drawings of them look too strange to be true4 ,so scepticism imputes to the draughtsman their artificial fashioning1 not realizing that by so doing it bears unconscious witness to their character4 ,for in order to disprove the deduction it is driven to deny the fact4 ,now the fact can look after itself and will be recognized in time4 ,for that the lines are as ,i have stated is beyond doubt4 ,each return of the planet shows them more and more geometric as sites are bettered and training improves4 ,suggestive of design as their initial appearance is1 the idea of artificiality receives further sanction from more careful consideration1 even from a static point of view1 on at least eight counts3-- #a4 ,their straightness2 #b4 ,their individually uniform size2 #c4 ,their extreme tenuity2 #d4 ,the dual character of some of them2 #e4 ,their position with regard to the planet's fundamental features2 #f4 ,their relation to the oases2 #g4 ,the character of these spots2 and1 finally1 #h4 ,the systematic networking by both canals and spots of the whole surface of the planet4 ,now1 no natural phenomena within our knowledge show such regularity on such a scale upon any one of these eight counts1 a fortiori upon all4 ,when one considers that these lines run for thousands of miles in an unswerving direction1 as far relatively as from ,london to ,bombay1 and as far actually as from ,boston to ,san ,francisco1 the inadequacy of natural explanation becomes glaring4 ,these several counts become more expressive of design the farther one looks into them4 ,straightness upon a sphere means the following of an arc of a great circle4 ,the lines1 then1 are arcs of great circles4 ,now1 the great circle course is the shortest distance connecting two given points4 ,the canals of ,mars1 then1 practice this economy2 they connect their terminals by the shortest1 that is1 other things equal1 by the quickest and least wasteful path4 ,their preserving a uniform width throughout this distance is an equally unnatural feature for any natural action to exhibit1 but a perfectly natural one for an unnatural agent4 ,for means of communication for whatever cause would probably be fashioned of like countenance throughout4 ,their extreme tenuity is a third trait pointing to artificiality2 inasmuch as the narrower they are1 the more probable is their construction by local intelligence4 ,even more inexplicable1 except from intent1 is their dual character4 ,for them to parallel one another like the twin rails of a railway track1 seems quite beyond the powers of natural causation4 ,enigmatic1 indeed1 from a natural standpoint1 they cease to be so enigmatic viewed from an artificial one2 and this the more by reason of what has lately been learnt of the character of their distribution4 ,that they are found most plentifully near the equator1 where the latitudinal girth is greatest1 and thence diminish in numbers to about latitude #fj1 where they disappear1--and this not relatively to the amount of surface but actually1--is very significant4 ,it is quite incapable of natural explanation1 and can only be accounted for on some theory of design such as lines of communication1 or canals conducting water down the latitudes for distribution4 ,so that this distribution of the doubles is in keeping with the law of development disclosed by the canals en masse4 ,channels and return-channels the two lines of the pair may be1 but about this we can at present posit nothing4 ,the relation may be of still greater complexity1 and we must carefully distinguish between surmise and deduction4 ,the position of the canals1 with regard to the main features of the disk1 has a cogency of its own1 an argument from time4 ,the places from which the lines start and to which they go are such as to imply a dependence of the latter upon the former chronologically4 ,the lines are logically superposed upon the natural features2 not as if they had grown there1 but as if they had been placed there for topographic cause4 ,those termini are used which we should ourselves select for stations of intercommunication4 ,for the lines not only leave important geodetic points1 but they travel directly to equally salient ones4 ,the connection of the canals with the oases is no less telltale of intent4 ,the spots are found only at junctions1 clearly the seal and sanction of such rendezvous4 ,their relation to the canals that enter them bespeaks method and design4 ,centring single lines1 they are inclosed by doubles1 a disposition such as would be true did they hold a pivotal position in the planet's economy4 ,the shape of the oases also suggests significance4 ,their form is round1 a solid circle of shading of so deep a tone as to seem black1 although undoubtedly in truth blue-green4 ,now1 a circular area has this peculiar property1 that it incloses for a given length of perimeter the maximum of space4 ,any other area has a longer inclosing boundary for the surface inclosed4 ,considering each area to be made up of onion-like envelops to an original core1 each similar in shape to the kernel1 we see that the property in question means that the average distance for points of the circular area from the centre is less than the same distance for those of any other figure4 ,this has immediate bearing on the possible fashioning of such areas4 ,for sufficient intelligence in the fashioners would certainly lead to a construction1 where the greatest area could be attended to at the least expenditure of force4 ,this would be where the distance to be traveled from the centre to all the desired points was on the average least2 that is1 the area would be round4 ,but last and all-embracing in its import is the system which the canals form4 ,instead of running at haphazard1 the canals are interconnected in a most remarkable manner4 ,they seek centres instead of avoiding them4 ,the centres are linked thus perfectly one with another1 an arrangement which could not result from centres1 whether of explosion or otherwise1 which were themselves discrete4 ,furthermore1 the system covers the whole surface of the planet1 dark areas and light ones alike1 a world-wide distribution which exceeds the bounds of natural possibility4 ,any force which could act longitudinally on such a scale must be limited latitudinally in its action1 as witness the belts of ,jupiter or the spots upon the sun4 ,rotational1 climatic1 or other physical cause could not fail of zonal expression4 ,yet these lines are grandly indifferent to such compelling influences4 ,finally1 the system after meshing the surface in its entirety runs straight into the polar caps4 ,it is1 then1 a system whose end and aim is the tapping of the snow-cap for the water there semiannually let loose2 then to distribute it over the planet's face4 ,function of this very sort is evidenced by the look of the canals4 ,further study during the last eleven years as to their behavior leads to a like conclusion1 while at the same time it goes much farther by revealing the action in the case4 ,this action proves to be not only in accord with the theory1 but interestingly explanatory of the process4 ,in the first place1 the canals have shown themselves1 as they showed to ,schiaparelli1 to be seasonal phenomena4 ,this negatives afresh the possibility of their being cracks4 ,but furthermore1 their seasonal behavior turns out to follow a law quite different from what we know on earth and betokens that they are indebted to the melting of the polar cap for their annual growth1 even more directly than to the sun1 and that vegetation is the only thing that satisfactorily accounts for their conduct4 ,but again this is not all4 ,their time of quickening proceeds with singular uniformity down the disk1 not only to1 but across the equator4 ,now1 this last fact has peculiar significance4 ,so large are the planetary masses that no substance can resist the strains due to the cosmic forces acting on them to change their shape till it becomes one of stable equilibrium4 ,thus a body of planetary size1 if unrotating1 becomes a sphere except for solar tidal deformation2 if rotating1 it takes on a spheroidal form exactly expressive1 as far as observation goes1 of the so-called centrifugal force at work4 ,mars presents such a figure1 being flattened out to correspond to its axial rotation4 ,its surface1 therefore1 is in fluid equilibrium1 or1 in other words1 a particle of liquid at any point of its surface at the present time would stay where it was1 devoid of inclination to move elsewhere4 ,now1 the water which quickens the verdure of the canals moves from the neighborhood of the pole down to the equator as the season advances4 ,this it does1 then1 irrespective of gravity4 ,no natural force propels it1 and the inference is forthright and inevitable that it is artificially helped to its end4 ,there seems to be no escape from this deduction4 ,water flows only downhill1 and there is no such thing as downhill on a surface already in fluid equilibrium4 ,a few canals might presumably be so situated that their flow could1 by inequality of terrane1 lie equatorward1 but not all4 ,as we see on the earth1 rivers flow impartially to all points of the compass1 dependent only upon unevenness of the local surface conditions4 ,now1 it is not in particular but by general consent that the canal system of ,mars develops from pole to equator4 ,from the respective times at which the minima take place1 it appears that the canal-quickening occupies fifty-two days1 as evidenced by the successive vegetal darkenings to descend from latitude #gb north to latitude #j1 a journey of #bfej miles4 ,this gives for the water a speed of fifty-one miles a day1 or #b4a miles an hour4 ,the rate of progression is remarkably uniform2 and this abets the deduction as to assisted transference4 ,the simple fact that it is carried from near the pole to the equator is sufficiently telltale of extrinsic aid1 but the uniformity of the action increases its significance4 ,but the fact is more unnatural yet4 ,the growth pays no regard to the equator1 but proceeds across it as if it did not exist into the planet's other hemisphere4 ,here is something still more telling than its travel to this point4 ,for even if we suppose1 for the sake of argument1 that natural forces took the water down to the equator1 their action must there be certainly reversed and the equator prove a dead-line to pass which were impossible4 ,,chapter ,,xxxii ,,conclusion ,that ,mars is inhabited by beings of some sort or other we may consider as certain as it is uncertain what those beings may be4 ,the theory of the existence of intelligent life on ,mars may be likened to the atomic theory in chemistry in that in both we are led to the belief in units which we are alike unable to define4 ,both theories explain the facts in their respective fields and are the only theories that do1 while as to what an atom may resemble we know as little as what a ,martian may be like4 ,but the behavior of chemic compounds points to the existence of atoms too small for us to see1 and in the same way the aspect and behavior of the ,martian markings implies the action of agents too far away to be made out4 ,but though in neither case can we tell anything of the ,bodily form of its unit1 we can in both predicate a good deal about their workings4 ,apart from the general fact of intelligence implied by the geometric character of their constructions1 is the evidence as to its degree afforded by the cosmopolitan extent of the action4 ,girdling their globe and stretching from pole1 to pole1 the ,martian canal system not only embraces their whole world1 but is an organized entity4 ,each canal joins another1 which in turn connects with a third1 and so on over the entire surface of the planet4 ,this continuity of construction posits a community of interest4 ,now1 when we consider that though not so large as the ,earth the world of ,mars is one of #dbjj miles diameter and therefore containing something like #bab1jjj1jjj of square miles1 the unity of the process acquires considerable significance4 ,the supposed vast enterprises of the earth look small beside it4 ,none of them but become local in comparison1 gigantic as they seem to us to be4 ,the first thing that is forced on us in conclusion is the necessarily intelligent and non-bellicose character of the community which could thus act as a unit throughout its globe4 ,war is a survival among us from savage times and affects now chiefly the boyish and unthinking element of the nation4 ,the wisest realize that there are better ways for practicing heroism and other and more certain ends of insuring the survival of the fittest4 ,it is something a people outgrow4 ,but whether they consciously practice peace or not1 nature in its evolution eventually practices it for them1 and after enough of the inhabitants of a globe have killed each other off1 the remainder must find it more advantageous to work together for the common good4 ,whether increasing common sense or increasing necessity was the spur that drove the ,martians to this eminently sagacious state we cannot say1 but it is certain that reached it they have1 and equally certain that if they had not they must all die4 ,when a planet has attained to the age of advancing decrepitude1 and the remnant of its water supply resides simply in its polar caps1 these can only be effectively tapped for the benefit of the inhabitants when arctic and equatorial peoples are at one4 ,difference of policy on the question of the all-important water supply means nothing short of death4 ,isolated communities cannot there be sufficient unto themselves2 they must combine to solidarity or perish4 ,from the fact1 therefore1 that the reticulated canal system is an elaborate entity embracing the whole planet from one pole to the other1 we have not only proof of the world-wide sagacity of its builders1 but a very suggestive side-light1 to the fact that only a universal necessity such as water could well be its underlying cause4 ,possessed of important bearing upon the possibility of life on ,mars is the rather recent appreciation that the habitat of both plants and animals is conditioned not by the minimum1 nor by the mean temperature of the locality1 but by the maximum heat attained in the region4 ,not only is the minimum thermometric point no determinator of a dead-line1 but even a mean temperature does not measure organic capability4 ,the reason for this is that the continuance of the species seems to depend solely upon the possibility of reproduction1 and this in turn upon a suitable temperature at the critical period of the plant's or animal's career4 ,contrary to previous ideas on the subject1 ,merriam found this to be the case with the fauna of the ,san ,francisco ,peak region in northern ,arizona4 ,the region was peculiarly fitted for a test1 because of rising a boreal island of life out of a sub-tropic sea of desert4 ,it thus reproduced along its flanks the conditions of climates farther north1 altitude taking the part of latitude1 one succeeding another until at the top stood the arctic zone4 ,merriam showed that the existence of life there was dependent solely upon a sufficiency of warmth at the breeding season4 ,if that were enough the animal or plant propagated its kind1 and held its foothold against adverse conditions during the rest of the year4 ,this it did by living during its brief summer and then going into hibernation the balance of the time4 ,nature in short suspended its functions to a large extent for months together1 enabling it to resurrect when the conditions turned4 ,hibernation proves thus to be a trait acquired by the organism in consequence of climatic conditions4 ,like all such it can only be developed in time1 since nature is incapable of abrupt transition4 ,an animal suddenly transported from the tropic to a sub-arctic zone will perish1 because it has not yet learnt the trick of winter sleeping4 ,while still characterized by seasonal insomnia it is incapable of storing its energies and biding its time4 ,but given time enough to acquire the art1 its existence is determined solely by the enjoyment of heat enough at some season to permit of the vital possibility of reproducing its kind4 ,diurnal shutting off of the heat affects the process but little1 provided the fall be not below freezing at the hottest season4 ,so much is shown by the fauna of our arctic and sub-arctic zones1 but still more pertinently to ,mars by the zones of the ,san ,francisco ,peak region1 since the thinner air of altitude1 through which a greater amount of heat can radiate off1 is there substituted for the thicker one of latitudinally equal isotherms4 ,here again with the diurnal as before with the seasonal it is the maximum1 not the mean1 or1 till low1 even the minimum temperature1 that tells4 ,now1 with ,mars the state of things is completely in accord with what is thus demanded for the existence of life4 ,the ,martian climate is one of extremes1 where considerable heat treads on the heels of great cold4 ,and the one of these two conditions is as certain as the other1 as the condition of the planet's surface shows conclusively4 ,in summer and during the day it must be decidedly hot1 certainly well above any possible freezing1 a thinner air blanket actually increasing the amount of heat that reaches the surface1 though affecting the length of time of its retention unfavorably4 ,the maximum temperature1 therefore1 cannot be low4 ,the minimum of course is2 but as we have just seen1 it is the maximum that regulates the possibility of life4 ,in spite1 therefore1 of a winter probably longer and colder than our own1 organic life is not in the least debarred from finding itself there4 ,indeed1 the conditions appear to be such as to put a premium upon life of a high order4 ,the ,martian year being twice as long as our own1 the summer is there proportionately extended4 ,even in the southern hemisphere1 the one where the summer is the shortest1 it lasts for #aeh days1 while at the same latitudes our own is but #ij days4 ,this lengthening of the period of reproduction cannot but have an elevating effect upon the organism akin to the prolongation of childhood pointed out by ,john ,fiske as playing so important a part in the evolution of the highest animals4 ,day and night1 on the other hand1 alternate there with approximately the same speed as here1 and except for what is due to a thinner air covering reproduce our own terrestrial diurnal conditions1 which as we saw are not inimical to life4 ,in this respect1 then1 ,mars proves to be by no means so bad a habitat4 ,it offers another example of how increasing knowledge widens the domain that life may occupy4 ,just as we have now found organic existence in abyssal depths of sea and in excessive degrees of both heat and cold1 so do we find from exploration of our island mountains1 which more than any other locality on earth facsimile the ,martian surface1 its possession there as well4 ,another point1 too1 is worth consideration4 ,in an aging world where the conditions of life have grown more difficult1 mentality must characterize more and more its beings in order for them to survive1 and would in consequence tend to be evolved4 ,to find1 therefore1 upon ,mars highly intelligent life is what the planet's state would lead one to expect4 ,to some people it may seem that the very strangeness of ,martian life precludes for it an appeal to human interest4 ,to me this is but a near-sighted view4 ,the less the life there proves a counterpart of our earthly state of things1 the more it fires fancy and piques inquiry as to what it be4 ,we all have felt this impulse in our childhood as our ancestors did before us1 when they conjured goblins and spirits from the vasty void1 and if our energy continue we never cease to feel its force through life4 ,we but exchange1 as our years increase1 the romance of fiction for the more thrilling romance of fact4 ,as we grow older we demand reality1 but so this requisite be fulfilled the stranger the realization the better we are pleased4 ,perhaps it is the more vivid imagination of youth that enables us all then to dispense with the hall-mark of actuality upon our cherished visions2 perhaps a deeper sense of our own oneness with nature as we get on makes us insist upon getting the real thing4 ,whatever the reason be1 certain it is that with the years a narration1 no matter how enthralling1 takes added hold of us for being true4 ,but though we crave this solid foothold for our conceptions1 we yield on that account no jot or tittle of our interest for the unexpected4 ,good reason we have for the allurement we feel toward what is least like us4 ,for the wider the separation from the familiar1 the greater the parallax the new affords for cosmic comprehension4 ,that which differs little yields little to the knowledge already possessed4 ,just as a longer base line gives us a better measure of the distance of the sun1 so here the more diverse the aspects1 the farther back they push the common starting-point and furnish proportionately comprehensive insight into the course by which each came to be what it is4 ,by studying others we learn about ourselves1 and though from the remote we learn less easily1 we eventually learn the more4 ,even on the side1 then1 that touches most men1 the personal1 the strangeness of the subject should to the far-seeing prove all the greater magnet4 ,one of the things that makes ,mars of such transcendent interest to man is the foresight it affords of the course earthly evolution is to pursue4 ,on our own world we are able only to study our present and our past2 in ,mars we are able to glimpse1 in some sort1 our future4 ,different as the course of life on the two planets undoubtedly has been1 the one helps1 however imperfectly1 to better understanding of the other4 ,another1 more abstract but no less alluring1 appeals to that desire innate in man to know about the cosmos of which he forms a part and which we call by the name of science4 ,study of ,mars responds to this craving both directly by revelation of the secrets of another world and indirectly by the bearing of what we thus learn upon our understanding of the laws of the universe4 ,for the facts thus acquired broaden our conceptions in every branch of science4 ,some day our own geology1 meteorology1 and the rest will stand indebted to study of the planet ,mars for advance along their respective lines4 ,already the most alert of those professing them are lending ear to information from this source1 and such cosmopolitanism can but increase as the years roll on4 ,today what we already know is helping to comprehension of another world2 in a not distant future we shall be repaid with interest1 and what that other world shall have taught us will redound to a better knowledge of our own1 and of that cosmos of which the two form part4 ,illustration3 ,lowell ,observatory4 ,,mars #aije4 ,,index ,adamas1 unmistakable double in #aijc1 #bad4 ,aeria1 white in1 #gf2 ruddy color of1 #adh4 ,air 7see ,atmosphere71 #hf2 necessity of1 to life1 #aff1 #afg2 as important to astronomical calculations1 #g4 ,air-waves1 #bej1 #bea1 #bgc4 ,albedo1 low1 #afb1 #afg4 ,alg1 #cdi4 ,amenthes1 hibernation of1 #cag-cbd4 ,animalcula1 in almost boiling geysers1 #cdi4 ,aonium ,sinus1 two doubles suspected in1 #bdb4 ,aquae ,calidae1 #bjh1 #bec1 #cae4 ,archan age of the earth1 #acb1 #acc1 #ach4 ,areography1 #bj-ca2 beginning and progress of1 #aji2 three periods in1 #bd4 ,arizona1 #af2 in desert belt1 #ac2 plateau of1 #ah4 ,arnon1 convergent double1 #bdj4 ,artificiality1 of canal system1 #cff1 #cfh1 #cfi1 #cgj1 #cgd2 of oases1 #cff1 #cga4 ,ascraeus ,lucus1 #cca2 embraced by the double ,gigas1 #beg4 ,astaboras1 connection with ,lucus ,ismenius1 #bfj-bfc4 ,atmosphere1 of ,mars1 #fb1 #fc1 #ga1 #gh1 #gi1 #hg2 shown to exist1 #hj1 #hb1 #hc1 #hd1 #afc1 #afg2 rare1 #he1 #hf1 #afb1 #afg2 effect on temperature1 #hj2 constituents of1 #afb1 #afd1 #aff1 #afh4 ,autumn1 length of ,martian1 in northern hemisphere1 #ce1 #dh2 in southern1 #ce1 #dh4 ,axial tilt1 #cd1 #cf1 #ee1 #aee1 #afa2 determinations of1 #cd1 #cf1 #aee2 determines character of seasons1 #cd1 #cf2 effect of1 on presentation of arctic and antarctic regions1 #gj2 effect of1 on temperature of arctic and temperate regions1 #hh4 ,bacteria1 plasm-eating beings1 #cec4 ,barometric pressure1 #fc1 #he4 ,beer1 #bc1 #bf1 #aji4 ,bilateralism1 #bjh2 inherent attribute of canals1 #bji4 ,blue band1 surrounding polar caps1 #ci1 #dj1 #db1 #dc1 #ef1 #fa1 #fc1 #ga1 #afa1 #afb1 #afh1 #cch1 #cci4 ,blue-green areas 7see ,dark ,regions71 #cb1 #fg1 #afc2 taken for seas1 #aaj4 ,british ,nautical ,almanac1 #ce4 ,brontes1 development of1 #cjd-cab4 ,cambrian era of ,earth1 #aci4 ,camera1 the1 #bgb2 advantage of1 #bgc2 slower than the eye1 #bgc2 stars the peculiar province of1 #bgc1 #bgd4 ,canals1 #aa1 #cb1 #afc2 discovery of1 #bd1 #bf2 considered straits1 #bg2 regularity of1 #bh1 #bi2 unnatural in look1 #agc2 manner of introduction of1 #agd2 conditions necessary to seeing of1 #agd-agg1 #bhb1 #bhc2 pencil-like lines1 #agg1 #agi1 #cfg2 definite in direction1 #agh2 name1 #ahj2 width of1 #agi1 #ahj1 #ahb2 length of1 #ahc2 visible by virtue of length1 #aha2 oddities of1 #ahc2 number of1 #ahd2 systematic arrangement of1 #ahd1 #ahe1 #ahg-aia1 #bdh2 connect with polar caps1 #cbe1 #cci1 #cgc2 import of system of1 #cch1 #cgb1 #cgc2 intrinsic change in1 #bhc1 #bhd1 #ccg1 #cch2 what they are not1 #ahe-ahg1 #cgc2 zonal distribution of1 #ahh1 #ahi2 departure-points1 #aij2 dependent on general topography1 #aia2 of later origin than main features1 #aia1 #bdg2 kinematic character of1 #bha-cjc2 effect on1 of illumination1 #bhd2 drawings of1 numerous and consecutive1 #bhf2 cordination of data1 #bhh1 #bhi2 curves of visibility of 7see ,cartouches71 #bhi1 #bij2 geometricism of1 #age1 #bjf1 #cfe1 #cfg1 #cfh2 polar1 #cbg4 ,canals in the dark regions1 #cj1 #ca1 #bdc-bdh2 of the southern hemisphere1 #bde2 of the northern hemisphere1 #bdf1 #bdg2 detection of1 #bdc1 #bde2 deprived seas of marine character1 #bdc2 part of canal system1 #bdd1 #bde1 #bdg4 ,caps 7see ,polar ,caps74 ,carbon dioxide1 #ci1 #afa1 #afd-afh4 ,carbonic era of ,earth1 #acd1 #ada1 #adb4 ,carets1 #bfe-bgj2 natural formations1 #bca1 #bcb2 form and position of1 #bff1 #bfg2 reason for shape of1 #bfh2 associated with canals1 #bfg1 #bfi2 help in solution of riddle1 #bgj2 act like oases1 #ccc4 ,cartouches of the canals1 #bhi-cjc2 interpretation of1 #bia-bic1 #bii-cjc1 #cdd-cdg2 arranged by latitudes1 #bid2 showing first frosts1 #bii2 minimum points of1 #big1 #cdd2 maximum point of1 #cja2 mean canal1 #big1 #bih4 ,cenozoic times1 #add4 ,cerberus1 obliterated by white spot1 #ge4 ,change1 #d1 #bha2 shown in polar caps1 #cg1 #cch2 in blue-green areas1 #aac1 #aad1 #aae1 #abj1 #abb-abg1 #afc1 #afd2 in canals1 #afh1 #afi1 #bje1 #bhc-bhe1 #cad1 #ccg1 #cch2 in oases1 #bej-beb1 #ccj1 #cca1 #ccg1 #cch4 ,chromacea1 #ceb2 plasm-forming beings1 #cec2 close to inorganic things1 #ceg2 in hot springs1 #ceg1 #ceh4 ,chryse1 #ij1 #ajb4 ,climate1 #hb-hi2 one of extremes1 #hg2 temperature1 theoretic and observed1 #hg2 non-glaciation the rule1 #hh4 ,clouds1 #ee1 #ga1 #gc1 #hi1 #afc1 #afe1 #bhc1 #bhd2 but few exist1 #hc1 #afe2 none over blue-green areas1 #ib2 of tawny dust color1 #ajf2 probably dust storms1 #afe2 prove existence of atmosphere1 #afg4 ,cold1 #hg1 #afg1 #bii4 ,coloe ,palus1 in connection with double canals1 #beg1 #beh1 #bfc4 ,color1 #gd1 #adh2 of ,mare ,erythraeum1 #abb4 ,conferv1 in almost boiling geysers1 #cdi1 #ceh4 ,cretaceous era of the earth1 #acf1 #adc1 #aea1 #aeb4 ,crystals1 conditions of formation1 #ceg4 ,dana1 #aca1 #aci1 #adj4 ,dark ,regions1 #abb-abe2 thought to be seas1 #aaj1 #aaa2 named in accordance1 #aaj1 #aac2 change in aspect cast doubt on marine character of1 #aac1 #aad2 change in1 considered seasonal1 #aae1 #abj1 #abg1 #afc1 #afd2 marine character lost1 #cj1 #aae-aah1 #afc1 #afd2 vegetation tracts1 #aai-abg1 #afc1 #afd1 #afh1 #afi1 #agj2 below level of surrounding surface1 #acj1 #afd2 former ocean basins1 #abj1 #abi1 #aca2 latitudinal development in1 #abc1 #abd1 #abf1 #abg4 ,dawes1 #ba1 #bc1 #bdi1 #bej1 #bfh4 ,day1 ,martian1 length of1 #cd1 #afj1 #aff4 ,desert regions of the earth1 #ac1 #adi-aee2 as observatory sites1 #ab1 #ac2 help explain ,mars1 #af1 #ag1 #aef2 color of1 #adi1 #aea2 compared with color of ,mars1 #aej1 #afc2 vegetation in1 #aej2 position of1 #aec1 #aed2 due to winds1 #aed4 ,desertism1 #af1 #hi1 #aec-aeh4 ,deserts 7see ,reddish-ochre regions74 ,deuteronilus1 #bei-bfa4 ,development of canals1 latitudinal law of1 #bii1 #cjb1 #cge2 follows melting of polar caps1 #cjb1 #cch-cdj2 across equator1 #cgc1 #cge4 ,devonian era of the earth1 #ada4 ,diaphragm1 the great1 #bfe4 ,diplopia1 #aif4 ,djihoun1 narrowest double1 #bbh-bcj2 embouchure of1 #bai-bbj2 connection with ,luci ,ismenii1 #bfj1 #bfb4 ,double ,canals1 first seen by ,schiaparelli1 #bh1 #aib2 impression of1 #aic1 #bjd2 two classes of1 #bbd2 require steady definition1 #aid2 phenomena of1 #aid1 #bje1 #bjh1 #bab1 #bac2 physical bond between the constituents of1 #bbf2 connection with bays1 #bcb2 optical theories of1 #aif-bjc2 not illusions1 #aie-bjc1 #bji2 widths of1 #bje1 #bjf1 #bba-bbd1 #bbi1 #bcj1 #bcc2 length of1 #bje2 seasonal change in1 #bje2 constituents of1 #bjd2 original line of1 #baf1 #bag2 number of1 #bje1 #bji2 list of1 #baj1 #baa2 gemination period of1 #bab1 #bac2 direction of1 #bcd-bcf2 zonal distribution of1 #bcf-bci1 #cgj2 distribution in longitude1 #bcf2 tropical phenomena1 #bci1 #bdj1 #bda1 #bdb2 compared with single canals1 #bdj2 convergent1 #bdj2 avoid blue-green areas1 #bda2 connect with blue-green areas1 #bdb4 ,dust storms1 #ij1 #afe4 ,earth1 tilt of axis of1 #cd2 seasons on1 #ce2 polar caps of1 #ch1 #da1 #dd1 #de1 #ea1 #ed1 #fi2 rainfall on1 #gi2 viewed from space1 #cdj2 vegetal quickening opposite to that on ,mars1 #cdd4 ,eccentricity of orbit1 effect on seasons1 #df1 #dh1 #eb4 ,elevations on limb1 #if1 #ig2 measurement of1 #ih4 ,elysium1 white in1 #ge1 #gf4 ,eocene era of the earth1 #add4 ,eopaleozoic era1 #adj4 ,euphrates1 #bba1 #bca1 #bdi1 #beh-bfa1 #bff1 #bfg1 #caf2 continuously double1 #bac2 curious relation to the ,portus ,sigaeus and ,phison1 #bah1 #bai4 ,evolution1 #cfb1 #cff1 #cfg2 planetary1 #cfc1 #cfd2 advance in1 dependent on environment1 #ade1 #adf4 ,exploration1 polar1 #ed4 ,eye1 relation to camera1 #bgb-bgd4 ,farms in ,kansas and ,dakota1 #cfc4 ,fastigium ,aryn1 #bfi2 origin of longitudes1 #bc1 #gd4 ,fauna1 #cfa2 of northern ,arizona1 #ah2 linked with flora1 #cdi1 #cej1 #ceh4 ,flagstaff1 ,arizona1 #af4 ,flammarion1 #ba1 #bc1 #bjb4 ,flora1 #cfa2 linked with fauna1 #cdi1 #cej1 #ceh2 fixtures1 #cfj4 ,focal length1 of objective in photographing canals1 #bge4 ,franz ,joseph ,land1 #de4 ,frosts1 first arctic1 #bii1 #cjj1 #cde2 suggestive of1 #hg4 ,galileo1 #bj1 #ci4 ,ganges1 #bgj2 peculiar development of1 #bbf-bbh2 widest double1 #bbh1 #bbi4 ,gemination1 #bad-bba2 seasonal phenomenon1 #bab1 #bac2 conditioned by convenience1 #bah-bba4 ,geology1 shows the growing of the land1 #aca-ach4 ,gigas1 embracing the ,ascraeus ,lucus1 #beg4 ,gihon1 embouchure of1 #bcb4 ,gravitation1 law of1 #afj4 ,gravity1 effect on atmosphere1 #fb2 force of1 on ,mars1 #fc4 ,green1 #ba1 #bc1 #bd4 ,habitability1 #aei4 ,haeckel1 #ceb1 #cec1 #ceg4 ,haze1 at melting of caps1 #ef1 #fd-ff1 #ij1 #ic1 #afe2 recurrent1 #id4 ,heat1 #df1 #dg1 #ej1 #adf1 #aee4 ,hellas1 #ha1 #ij1 #ia2 in winter1 #eh1 #ei2 ruddy color of1 #adh4 ,herschel1 ,sir ,w41 #cd1 #cg4 ,hibernation of canals1 #cac-cbd1 #cgi4 ,hiddekel1 embouchure of1 #bcb2 connection with ,luci ,ismenii1 #bfj-bfb4 ,hippalus1 identical with rift1 #cbf1 #cbg4 ,hoarfrost1 #gh1 #gi1 #ha2 at equator1 #gi2 in southern hemisphere1 #hj1 #ib4 ,huyghens1 #bc1 #bf1 #ajh4 ,ice sheet1 effect of1 #eb4 ,illumination1 oblique1 #ig2 for measuring elevations1 #ih4 ,illusion theories of canals1 disproved1 #bic4 ,image of sun1 not reflected from dark areas1 #aab4 ,insolation1 #dg1 #gi1 #ia4 ,intelligence on other worlds1 method of making itself known1 #cfd4 ,islands south1 #ia1 #bdd2 effect of1 on isothermal lines1 #ib4 ,jamuna1 original line of1 #baf1 #bag4 ,jaxartes1 polar canal1 #cbh4 ,jupiter1 #cc1 #cgb4 ,jurassic era of the earth1 #acf1 #adc1 #add4 ,juturna ,fons1 a square oasis1 #bfc4 ,kaiser1 #ba1 #bc1 #bdi4 ,kinetic theory of gases1 #hc1 #adf1 #adg1 #afd4 ,kison1 convergent double1 #bdj4 ,lacus ,hyperboreus1 #bdf4 ,lampland1 #aig1 #bbe1 #bge4 ,lick ,observatory1 #ajj4 ,life1 necessity of air and water to1 #ag1 #aff1 #afg1 #cda2 thin cold air no bar to1 #ah2 maximum temperature determinative of1 #ai1 #cgh1 #chj4 ,life on ,earth1 #cdi-cec2 dependent on conditions1 #cdi-cee1 #ceg1 #cgi1 #chj4 ,life on ,mars1 #afi1 #cgf2 vegetal1 #cdh1 #cei2 probably of high order1 #cdh1 #cei1 #cgg1 #cgh1 #cha1 #chb2 evidence of1 #cfj-cfe4 ,limb-light1 evidence of atmosphere1 #hd1 #afb1 #afg4 ,longitudes1 origin of1 #bc1 #gd4 ,lowell ,observatory1 ,annals1 #ca1 #ha2 ,bulletin1 #bja4 ,lucus ,ismenius1 #ai1 #beh2 only double oasis1 #bei2 association with canals1 #bfj1 #bfa4 ,lucus ,lunae1 #ccj4 ,lucus ,moeris1 #bjh4 ,maedler1 #ba1 #bc1 #bf1 #aji4 ,mammal1 #cdi4 ,maps1 of ,mars1 #bj-bd1 #bf-bi4 ,mare ,acidalium1 #aae1 #bdb1 #bdf-beb2 white in1 #hj2 darker than the ,mare ,erythraeum1 #abg4 ,mare ,cimmerium1 #bfg4 ,mare ,erythraeum1 #aac2 irregular lines in1 #cj2 in #aijc1 #abb-abd2 in #aije1 #abd-abf4 ,mare ,icarium1 #bjg4 ,mare ,sirenum1 #ib1 #aaj1 #aad1 #bfg4 ,maria1 on the moon1 #aji1 #aaa2 not seas1 #aab1 #aac2 on ,mars1 #aaj2 not seas1 #aag2 southern hemisphere1 #ca4 ,matter1 distribution of1 #cee4 ,mercator's projection1 #bb1 #cdd4 ,merriam1 #ah1 #ai1 #cgi4 ,mesozoic times of the earth1 #ace1 #adb1 #add1 #aea4 ,meteorology of ,mars1 #fc1 #ic4 ,moisture1 #hf1 #aed4 ,monera1 #cdi1 #ceg2 suggestive of crystals1 #cef4 ,months1 ,martian1 different from our own1 #cf4 ,mountains1 not visible on ,mars1 #ajj2 measurement of1 #ig-ajj2 limit of height visible1 #ajj2 on ,moon1 #ih1 #ii4 ,naarmalcha1 association with ,luci ,ismenii1 #bfj1 #bfa4 ,ngeli1 #cef4 ,nansen1 #ed4 ,naval ,observatory at ,washington1 #af4 ,nectar1 shows white1 #ei4 ,neopaleozoic times of the ,earth1 #adj4 ,neptune1 #cc4 ,nicks in the coastline 7see ,carets74 ,nilokeras1 double1 #bji2 photographed1 #bbe4 ,nilosyrtis1 unlike other canals1 #bfb4 ,nitro-bacteria1 #cej1 #cec4 ,nitrogen1 #hc1 #afd1 #aff1 #cda4 ,nix ,olympica1 #gd1 #gh4 ,north ,america1 geologic history of1 #acc-acg4 ,oases1 detected later than canals1 #cj1 #bdi2 three stages in appearance of1 #bej-beb2 number of1 #beb2 kinds of1 #beb-bed1 #bfc2 shape of1 #bec1 #cga2 position of1 #bed-beg1 #bfc2 connected with canals1 #bef1 #beg1 #bfb1 #cga2 disprove diplopic theory1 #beh2 objectivity of1 #bfc2 in dark regions1 #afc1 #bdd1 #bfc1 #bfd2 kinematic character of1 #ccj-ccc2 latitudinal progress of change in oases1 #cca2 evolution of1 #cca1 #ccb2 intrinsic change in1 #ccg1 #cch2 at junction of canals only1 #bee1 #cga4 ,observations1 mutual corroboration of1 #afe1 #aff2 among mountains1 #g4 ,organic ,evolution1 origin of1 #cef4 ,orology1 of ,mars1 #fb4 ,ovid1 #be4 ,oxygen1 #hc1 #afd1 #aff1 #afg1 #cda4 ,paleozoic times on the ,earth1 #ace4 ,permian period1 #adb4 ,personal equation1 eliminated1 #bhg4 ,phenological quickening1 on ,earth1 #cdb2 on ,mars1 #cdc4 ,phison1 #bba1 #bca1 #bdi1 #beh1 #bff1 #bfg1 #caf2 continuously double1 #bac2 connection with ,euphrates and ,portus ,sigaeus1 #bah1 #bai4 ,phnix ,lake1 #ccj4 ,photographs of the canals1 #bbe1 #bge-bgg4 ,photography1 celestial1 #bga-bgg4 ,physiographic conditions1 on ,mars1 #fh1 #abh4 ,pickering1 ,w4 ,h41 #ccj4 ,pierius1 #ga4 ,polar caps1 phenomena of1 #cg1 #da1 #fa2 key to comprehension of planet1 #cg2 compared with those of earth1 #da1 #df2 composition of1 #ci1 #afa1 #afh1 #cci2 making of new1 #id2 position of1 #fh2 aspect of1 #ef1 #eg2 maxima and minima of1 #ch1 #da-dd1 #dg-ec1 #ee-eg1 #ff-fh1 #afb2 fission of1 #fa4 ,polar seas 7see ,blue band72 fresh water1 #afb4 ,poles1 ,martian1 determination of1 #cf4 ,pons ,hectoris1 #gh4 ,portus ,sigaeus1 nicks in the coastline1 #bjg1 #bff1 #bfg2 embouchure to ,phison and ,euphrates1 #bah4 ,precipitation1 #ea1 #gi1 #aed1 #aee2 effect on glaciation1 #eb4 ,presentation1 a1 defined1 #bhg1 #bhh4 ,probability1 law of1 #afj4 ,projections on the terminator1 #gg1 #ha1 #if1 #ajj1 #ajd1 #afe2 color of1 #ajb2 cause of1 #ajd-ajg2 great one of #aijc1 #aja-ajd2 of #aijj1 #ajd4 ,propontis1 the1 #bdb2 canals in1 #bdg2 oases in1 #bef4 ,protonilus1 association with ,luci ,ismenii1 #bfj4 ,pseboas ,lucus1 #bjg1 #bej1 #bec1 #bfc2 anomalous position of1 #bfb4 ,quaternary epoch of the ,earth1 #acg4 ,reddish-ochre regions1 #aec1 #aee2 deserts1 #adi1 #aef1 #afc2 variations of tint in1 #cb1 #adh1 #adi1 #aea4 ,rifts in polar cap1 #fa-fc1 #fg1 #afb1 #cbe-cbi2 permanent in place1 #fa1 #fb2 not depressions1 #fb1 #fc1 #afb2 coincide with canals1 #cbf-cbh2 explanation of1 #cbh1 #cbi4 ,rotation1 early noted1 #ajh1 #aji2 how determined1 #cd2 time of1 #cd1 #afj2 disclosed by markings1 #cb-cd1 #ajh4 ,sabaeus ,sinus1 #bc1 #bjg1 #bfh1 #bfi4 ,san ,francisco ,peaks1 #ah1 #ai1 #adi1 #cgi1 #chj4 ,saturn1 #cc4 ,scepticism1 #bg1 #bh1 #bjd4 ,schaeberle1 #cj4 ,schiaparelli1 #aa1 #ae1 #ba1 #bc1 #bd1 #bf1 #bg1 #bi1 #cj1 #ca1 #cd1 #fh1 #gd1 #ge1 #ha1 #aad1 #aae1 #abj1 #aba1 #agc1 #agg1 #ahf1 #aib1 #bab1 #bag1 #bba1 #bdg1 #bdi1 #bfe1 #bhb1 #cac1 #cad1 #cbe1 #ccg1 #cfg1 #cgc4 ,seas 7see ,dark ,regions74 southern1 #ib2 formerly on ,mars and the ,moon1 #abi2 internal absorption of1 #adg4 ,seasonal change1 metabolic1 #afi2 in canals1 #afh1 #afi1 #bhe1 #cgc4 ,seasons1 like our own1 #cd1 #ce1 #aff2 length of1 #dh1 #gi1 #afa2 of vegetal growth1 #cdf1 #cdg4 ,secular change1 in canals1 #cad4 ,silurian era of the ,earth1 #acd1 #ach1 #adj4 ,sky1 blotting out of1 #ad2 measure of extinction of1 #af4 ,sky1 ,martian1 #hi2 clear1 #afe4 ,slipher1 #aja1 #ajc4 ,snow1 #cde2 limits of1 on ,earth and ,mars1 #ajh4 ,solis ,lacus1 #bc1 #bdb4 ,spring1 ,martian1 #ce1 #dh2 haze in1 #id4 ,s4,s4 ,challenger1 concerning south polar cap of earth1 #de4 ,s4,s4 ,pagoda1 #de4 ,subsidiary snow patches1 #fg1 #gc4 ,summer1 ,martian1 length of1 #ce1 #dh1 #cha4 ,surface1 relatively flat1 #fb1 #gf1 #ig1 #afd2 covered by canal network1 #bdc2 clear-cut in good air1 #beh2 in fluid equilibrium1 #cgd2 indicative of thin air1 #afb1 #afg4 ,surface features1 reality of1 proved1 #bf1 #cc4 ,syrtis ,major1 #bb2 first marking made out1 #bc4 ,tempe1 white in1 #gg1 #hj4 ,temperature1 #gh1 #adg1 #afe1 #aff2 effect on life1 #ceh4 ,terminator1 projections on1 #gg1 #ha1 #if1 #ajj-ajg1 #aad1 #afe2 depressions on1 #afd4 ,terrane1 #ajh1 #bfe4 ,terraqueousness1 shown by earth1 #abh1 #aca4 ,terrestriality1 follows terraqueousness1 #abi1 #aca1 #acg1 #add-adf2 earth's oceans contracting in size1 #aca2 inevitably1 #aca1 #adf2 as shown by ,mars and the ,moon1 #abh1 #acj1 #aca2 as shown by the geologic history of earth1 #aca-acg2 as shown by paleontology1 #ach-add2 making a better habitat1 #ade1 #adf4 ,tertiary times of the ,earth1 #acg1 #aea4 ,thoth-,nepenthes1 peculiar course of1 #bjh2 hibernation of1 #cae-cbd4 ,titan1 #cje4 ,triassic era1 #acf1 #adb1 #aeb4 ,trivium ,charontis1 canals and oases in1 #bea1 #beb1 #bef4 ,twilight arc1 shows thin air1 #he1 #afb4 ,uranus1 #cc4 ,vegetation1 #gi1 #aai-abg1 #afc1 #aff1 #afi1 #cja2 color of ,mare ,erythraeum1 #abb-abf2 proof of1 #agj2 theory supported by rifts in polar cap1 #cbi2 most satisfactory explanation of phenomena of canals1 #cci1 #cda1 #cdd1 #cde1 #cdg1 #cdh1 #cgc2 two seasons of growth of1 #cdf2 melts snow1 #cbh4 ,water1 dearth of1 #abh1 #afa1 #afc1 #aff1 #afh1 #afi1 #cda1 #cff2 loss of1 inevitable1 #aca2 speed of flow of1 #cge2 from polar caps1 #cdj1 #cgd4 ,water-vapor1 from polar caps1 #hc2 in atmosphere1 #afb1 #afh4 ,weather1 #ff1 #hi1 #ie4 ,wedge of ,casius1 #bdb2 canals in1 #bdg2 oases in1 #bea1 #beb1 #bef4 ,welkin1 man-manufactured1 #ac-ae4 ,white spots1 #cb1 #afe2 similar in look to polar caps1 #gc2 location and season of1 #gd1 #gf-gi1 #hj1 #ha2 ,white spots1 permanency of1 #gc1 #gf2 indication of temperature1 #hj1 #afe4 ,winds1 #aed4 ,winter1 ,martian1 #ce1 #dh4 ,world1 ,mars another1 #d1 #e1 #afi2 evolution of a1 #af1 #abh1 #aca1 #aee-aeh1 #ceh4 ,year1 of ,earth1 #ce2 of ,mars1 #ce1 #afa4 ,a ,,compendium ,,of ,,spherical ,,astronomy ,with its applications to the determination and reduction of positions of the fixed stars ,by ,,simon ,,newcomb ,cloth #hvo #c4jj net -------------- ,,contents ,,part ,i4 ,,preliminary ,,subjects ,,chapter ,i4 ,,introductory4 ,,notes ,,and ,,references4 ,,chapter ,,ii4 ,,differences1 ,,interpolation1 ,,and ,,development4 ,,notes ,,and ,,references4 ,,chapter ,,iii4 ,,the ,,method ,,of ,,least ,,squares4 ,section ,i4 ,mean ,values of ,quantities4 ,,ii4 ,determination of ,probable ,errors4 ,,iii4 ,equations of ,condition4 ,,notes ,,and ,,references4 ,,part ,,ii4 ,,the ,,fundamental ,,principles ,,of ,,spherical ,,astronomy ,,chapter ,,iv4 ,,spherical ,,co,,rdinates4 ,section ,i4 ,general ,theory4 ,,ii4 ,problems and ,applications of the ,theory of ,spherical ,cordinates4 ,,chapter ,v4 ,,the ,,measure ,,of ,,time ,,and ,,related ,,problems4 ,section ,i4 ,solar and ,sidereal ,time4 ,,ii4 ,the ,general ,measure of ,time4 ,,iii4 ,problems ,involving ,time4 ,,chapter ,,vi4 ,,parallax ,,and ,,related ,,subjects4 ,section ,i4 ,figure and ,dimensions of the ,earth4 ,,ii4 ,parallax and ,semi-diameter4 ,,chapter ,,vii4 ,,aberration4 ,,chapter ,,viii4 ,,astronomical ,,refraction4 ,section ,i4 ,the ,atmosphere as a ,refracting ,medium4 ,,ii4 ,elementary ,exposition of ,atmospheric ,refraction4 ,,iii4 ,general ,investigation of ,astronomical ,refraction4 ,notes and ,references to ,refraction4 ,,chapter ,,ix4 ,,precession ,,and ,,nutation4 ,section ,i4 ,laws of the ,precessional ,motion4 ,,ii4 ,relative ,positions of the ,equator and ,equinox at ,widely ,separated ,epochs4 ,,iii4 ,nutation4 ,notes and ,references to ,precession and ,nutation4 ,,part ,,iii4 ,,reduction ,,and ,,determination ,,of ,,positions ,,of ,,the ,,fixed ,,stars ,,chapter ,x4 ,,reduction ,,of ,,mean ,,places ,,of ,,the ,,fixed ,,stars ,,from ,,one ,,epoch ,,to ,,another4 ,section ,i4 ,the ,proper ,motions of the ,stars4 ,,ii4 ,trigonometric ,reduction for ,precession4 ,,iii4 ,development of the ,cordinates in the ,powers of the ,time4 ,,notes ,,and ,,references4 ,,chapter ,,xi4 ,,reduction ,,to ,,apparent ,,place4 ,section ,i4 ,reduction to ,terms of the ,first ,order4 ,,ii4 ,rigorous ,reduction for ,close ,polar ,stars4 ,,iii4 ,practical ,methods of ,reduction4 ,,iv4 ,construction of ,tables of the ,apparent ,places of ,fundamental ,stars4 ,notes and ,references4 ,,chapter ,,xii4 ,,method ,,of ,,determining ,,the ,,positions ,,of ,,stars ,,by ,,meridian ,,observations4 ,section ,i4 ,method of ,determining ,right ,ascensions4 ,,ii4 ,the ,determination of ,declinations4 ,,chapter ,,xiii4 ,,methods ,,of ,,deriving ,,the ,,positions ,,and ,,proper ,,motions ,,of ,,the ,,stars ,,from ,,published ,,results ,,of ,,observations4 ,section ,i4 ,historical ,review4 ,,ii4 ,reduction of ,catalogue ,positions of ,stars to a ,homogeneous ,system4 ,,iii4 ,methods of ,combining ,star ,catalogues4 ,,notes ,,and ,,references ,list of ,independent ,star ,catalogues4 ,catalogues made at ,northern ,observatories4 ,catalogues made at ,tropical and ,southern ,observatories4 ,,appendix ,,explanation ,,of ,,the ,,tables ,,of ,,the ,,appendix4--,i4 ,constants and ,formul in ,frequent ,use4 ,,ii4 ,tables ,relating to ,time and ,arguments for ,star ,reductions4 ,,iii4 ,centennial ,rates of the ,precessional ,motions4 ,,iv4 ,tables and ,formul for the ,trigonometric ,reduction of ,mean ,places of ,stars4 ,v4 ,reduction of the ,struve-,peters ,precessions to the ,adopted ,values4 ,,vi4 ,conversion of ,longitude and ,latitude into ,r4 ,a4 and ,dec4 ,,vii4 ,refractions4 ,,viii4 ,coefficients of ,solar and ,lunar ,nutation4 ,,ix4 ,three-place ,logarithms and ,trigonometrical ,functions4 -------------- ,,the ,,macmillan ,,company1 #fd-ff ,fifth ,avenue1 ,new ,york ,transcriber's ,notes ,ditto marks have been replaced by the text they represent4 ,some presumed printer's errors have been corrected1 including normalizing punctuation4 ,further corrections are listed below3 ,printed text ,corrected text ,page ,,mitglied ,,der ,,mitglied ,,der ,,astronomische ,,gesellschaft ,,astronomischen ,,gesellschaft ,title page terrrane terrane #ajh seem seems #bdg