,,getting ,,gold3 ,a ,,practical ,,treatise ,,for ,,prospectors1 ,,miners1 ,,and ,,students4 ,by ,j4 ,c4 ,f4 ,johnson1 ,f4 ,g4 ,s41 ,,member ,,of ,,the ,,aust4 ,,inst4 ,,of ,,mining ,,engineers2 ,,author ,,of ,,practical ,,mining1 ,,the ,,genesiology ,,of ,,gold1 ,,etc4 ,,preparer',s ,,note ,this text was prepared from a #ahih edition1 published by ,charles ,griffin ,company1 ,limited2 ,exeter ,street1 ,strand1 ,london4 ,it is the second edition1 revised4 ,numerous drawings and diagrams have been omitted4 ,,preface ,some six years ago the author published a small book entitled ,practical ,mining1 designed specially for the use of those engaged in the always fascinating1 though not as invariably profitable1 pursuit of ,getting ,gold4 ,of this ten thousand copies were sold1 nearly all in ,australasia1 and the work is now out of print4 ,the ,london ,mining ,journal of ,september #ith1 #ahia1 said of it3 ,we have seldom seen a book in which so much interesting matter combined with useful information is given in so small a space4 ,the gold-mining industry has grown considerably since #ahia1 and it appeared to the writer that the present would be a propitious time to bring out a similar work1 but with a considerably enlarged scope4 ,what has been aimed at is to make ,getting ,gold a compendium1 in specially concrete form1 of useful information respecting the processes of winning from the soil and the after-treatment of gold and gold ores1 including some original practical discoveries by the author4 ,practical information1 original and selected1 is given to mining company directors1 mine managers1 quartz mill operators1 and prospectors4 ,in ,rules of ,thumb1 chapters ,,xi4 and ,,xii41 will be found a large number of useful hints on subjects directly and indirectly connected with gold-mining4 ,the author's mining experience extends back thirty years and he therefore ventures to believe with some degree of confidence that the information1 original or compiled1 which the book contains1 will be found both useful and profitable to those who are in any capacity interested in the gold-mining industry4 ,j4 ,c4 ,f4 ,j4 ,,london1 ,november1 #ahif4 ,,getting ,,gold ,,chapter ,i ,,introductory ,,gold is a name to charm by4 ,it is desired by all nations1 and is the one metal the supply of which never exceeds the demand4 ,some one has aptly said1 ,gold is the most potent substance on the surface of our planet4 ,tom ,hood sings3 ,gold1 gold1 gold1 gold6 ,bright and yellow1 hard and cold2 ,molten1 graven1 hammered1 rolled1 ,heavy to get1 and light to hold2 ,stolen1 borrowed1 squandered1 doled4 ,that this much appreciated metal is heavy to get is proved by the high value which has been placed on it from times remote to date1 and that it is light to hold most of us know to our cost4 ,we read no farther than the second chapter in the ,bible when we find mention of gold4 ,there ,moses speaks of the land of ,havilah1 where there is gold2 and in ,genesis1 chapter xxiv41 we read that ,abraham's servant gave ,rebekah an earring of half a shekel weight1 say #e dwt4 #ac grs41 and two bracelets of ten shekels weight1 or about #d #a_/b ozs4 ,then throughout the ,scriptures1 and1 indeed1 in all historic writings1 we find frequent mention of the king of metals1 and always it is spoken of as a commodity highly prized4 ,i have sometimes thought1 however1 that either we are mistaken in the weights used by the ,hebrew nation in early days1 or that the arithmetic of those times was not quite according to ,cocker4 ,we read1 ,i4 ,kings x4 and xli41 that ,solomon in one year received no less than six hundred and three score and six talents of gold4 ,if a talent of gold was1 as has been assumed1 #cjjj shekels of #bai grains each1 the value of the golden treasure accumulated in this one year by the ,hebrew king would have been #c1fdf1cej pounds sterling4 ,considering that the only means of getting gold in those days was a most primitive mode of washing it from river sands1 or a still more difficult and laborious process of breaking the quartz from the lode without proper tools or explosives1 and then slowly grinding it by hand labour between two stones1 the amount mentioned is truly enormous4 ,of this treasure the ,queen of ,sheba1 who came to visit the ,hebrew monarch1 contributed a hundred and twenty talents1 or1 say1 #fjj1jjj pounds worth4 ,where the ,land of ,ophir1 whence this golden lady came1 was really situated has evoked much controversy1 but there is now a general opinion that ,ophir was on the east coast of ,africa1 somewhere near ,delagoa ,bay1 in the neighbourhood of the ,limpopo and ,sabia rivers4 ,it should be mentioned that the name of the black but comely queen was ,sabia1 which may or may not be a coincidence1 but it is certainly true that the rivers of this district have produced gold from prehistoric times till now4 ,the discovery of remarkable ruins in the newly acquired province of ,mashonaland1 which evince a high state of civilisation in the builders1 may throw some light on this interesting subject4 ,the principal value of gold is as a medium of exchange1 and its high appreciation is due1 first1 to the fact that it is in almost universal request2 and1 secondly1 to its comparative scarcity2 yet1 oddly enough1 with the exception of that humble but serviceable metal iron1 gold is the most widely distributed metal known4 ,few1 if any1 countries do not possess it1 and in most parts of the world1 civilised and uncivilised1 it is mined for and brought to market4 ,the torrid1 temperate1 and frigid zones are almost equally auriferous4 ,siberia1 mid-,asia1 most parts of ,europe1 down to equatorial and southern ,africa in the ,old ,world1 and north1 central1 and southern ,america1 with ,australasia1 in what may be termed the ,new ,world1 are all producers of gold in payable quantities4 ,in the earlier ages1 the principal source of the precious metal was probably ,africa1 which has always been prolific in gold4 ,to this day there are to be seen in the southern provinces of ,egypt excavations and the remains of old mine buildings and appliances left by the ancient gold-miners1 who were mostly ,state prisoners4 ,some of these mines were worked by the ,pharaohs of1 and before1 the time of ,moses2 and in these dreadful places thousands of ,israelites were driven to death by the taskmaster's whip4 ,amongst the old appliances is one which approximated very closely to the amalgamating1 or blanket table1 of a modern quartz mill4 ,the grinding was done between two stones1 and possibly by means of such primitive mechanism as is used to-day by the natives of ,korea4 ,the ,korean ,mill is simply a large hard stone to which a rocking motion is given by manual power by means of the bamboo handles while the ore is crushed between the upper and basement stone4 ,solomon says there is no new thing under the sun2 certainly there is much that is not absolutely new in appliances for gold extraction4 ,i lately learned that the principle of one of our newest concentrating machines1 the ,frue vanner1 was known in ,india and the ,east centuries ago2 and we have it on good authority--that of ,pliny--that gold saving by amalgamation with mercury was practised before the ,christian era4 ,it will not be surprising then if1 ere long1 some one claims to have invented the ,korean ,mill1 with improvements4 ,few subjects in mineralogical science have evoked more controversy than the origin of gold4 ,in the ,middle ,ages1 and1 indeed1 down to the time of that great philosopher1 ,sir ,isaac ,newton1 who was himself bitten with the craze1 it was widely believed that1 by what was known as transmutation1 the baser metals might be changed to gold2 and much time and trouble were expended in attempts to make gold--needless to say without the desired result4 ,doubtless1 however1 many valuable additions to chemical science1 and also some useful metallic alloys1 were thus discovered4 ,the latest startling statement on this subject comes from1 of course1 the wonderland of the world1 ,america4 ,in a recently published journal it is said that a scientific metallurgist there has succeeded in producing absolutely pure gold1 which stands all tests1 from silver4 ,needless to say1 if this were true1 at all events the much vexed hi-metallic question would be solved at once and for all time4 ,it is now admitted by all specialists that the royal metal1 though differing in material respects in its mode of occurrence from its useful but more plebeian brethren of the mineral kingdom1 has yet been deposited under similar conditions from mineral salts held in solution4 ,the first mode of obtaining this much desired metal was doubtless by washing the sand of rivers which flowed through auriferous strata4 ,some of these1 such as the ,lydian stream1 ,pactolus1 were supposed to renew their golden stores miraculously each year4 ,what really happened was that the winter floods detached portions of auriferous drift from the banks1 which1 being disintegrated by the rush and flow of the water1 would naturally deposit in the still reaches and eddies any gold that might be contained therein4 ,the mode of washing was exactly that carried on by the natives in some districts of ,africa to-day4 ,a wooden bowl was partly filled with auriferous sand and mud1 and1 standing knee-deep in the stream1 the operator added a little water1 and caused the contents of the bowl to take a circular motion1 somewhat as the modern digger does with his tin dish1 with this difference1 that his ancient prototype allowed the water and lighter particles to escape over the rim as he swirled the stuff round and round4 ,i presume1 in finishing the operation1 he collected the golden grains by gently lapping the water over the reduced material1 much as we do now4 ,i have already spoken of the mode in which auriferous lode-stuff was treated in early times--i4e41 by grinding between stones4 ,this is also practised in ,africa to-day1 and we have seen that the ,koreans1 with ,mongolian acuteness1 have gone a step farther1 and pulverise the quartz by rocking one stone on another4 ,in ,south ,america the arrastra is still used1 which is simply the application of horse or mule power to the stone-grinding process1 with use of mercury4 ,the principal sources of the gold supply of the modern world have been1 first1 ,south ,america1 ,transylvania in ,europe1 ,siberia in ,asia1 ,california in ,north ,america1 and ,australia4 ,africa has always produced gold from time immemorial4 ,the later development in the ,johannesburg district1 ,transvaal1 which has absorbed during the last few years so many millions of ,english capital1 is now1 after much difficulty and disappointment--thanks to ,british pluck and skill--producing splendidly4 ,the yield for #ahif was #b1bha1hgd ounces--a yield never before equalled by lode-mining from one field4 ,in the year #ahdg gold was discovered in ,california1 at ,sutor's sawmill1 ,sacramento ,valley1 where1 on the water being cut off1 yellow specks and small nuggets were found in the tail race4 ,the enormous rush which followed is a matter of history and the subject of many romances1 though the truth has1 in this instance1 been stranger than fiction4 ,the yield of the precious metal in ,california since that date up to #ahhh amounts to #bef1jjj1jjj pounds4 ,following close on the ,american discovery came that of ,australia1 the credit of which has usually been accorded to ,hargraves1 a returned ,californian digger1 who washed out payable gold at ,lewis ,ponds ,creek1 near ,bathurst1 in #ahea4 ,but there is now no reason to doubt that gold had previously been discovered in several parts of that great island continent4 ,it may be news to many that the first gold mine worked in ,australia was opened about twelve miles from ,adelaide city1 ,s4,a41 in the year #ahdh4 ,this mine was called the ,victoria2 several of the ,company's scrip are preserved in the ,public ,library2 but some two years previous to this a man named ,edward ,proven had found gold in the same neighbourhood4 ,most ,governments nowadays encourage in every possible way the discovery of gold-fields1 and rewards ranging from hundreds to thousands of pounds are given to successful prospectors of new auriferous districts4 ,the reward the ,new ,south ,wales authorities meted out to a wretched convict1 who early in this century had dared to find gold1 was a hundred lashes vigorously laid on to his already excoriated back4 ,the man then very naturally admitted that the alleged discovery was a fraud1 and that the nugget produced was a melted down brass candlestick4 ,one would have imagined that even in those unenlightened days it would not have been difficult to have found a scientist sufficiently well informed to put a little nitric acid on the supposed nugget1 and so determine whether it was the genuine article1 without skinning a live man first to ascertain4 ,my belief is that the unfortunate fellow really found gold1 but1 as ,mr4 ,deas ,thompson1 the then ,colonial ,secretary1 afterwards told ,hargraves in discouraging his reported discovery1 ,you must remember that as soon as ,australia becomes known as a gold-producing country it is utterly spoiled as a receptacle for convicts4 ,this1 then1 was the secret of the unwillingness of the authorities to encourage the search for gold1 and it is after all due to the fact that the search was ultimately successful beyond all precedent1 that ,australia has been for so many years relieved of the curse of convictism1 and has ceased once and for all to be a depot for the scoundrelism of ,britain--,hurrah for the bright red gold6 ,since the year #ahea to date the value of the gold raised in the ,australasian colonies has realised the enormous amount of nearly #eej1jjj1jjj pounds4 ,one cannot help wondering where it all goes4 ,mulhall gives the existing money of the world at #bdcg million pounds1 of which #hdf millions are paper1 #hja millions silver1 and #gij millions gold4 ,from #ahcj to #ahhj the world consumed by melting down plate1 etc41 #dbcj tons of silver more than it mined4 ,from #ahjj to #ahgj the value of gold was about #ae #a_/b times that of silver4 ,from #ahgj to #ahhj it was #afg times the value of silver and now exceeds it over twenty times4 ,in #agjj the world had #cja million pounds of money2 in #ahjj1 #efh million pounds2 and in #ahfj1 #aahj million pounds sterling4 ,the gold first worked for in ,australia1 as in other places1 was of course alluvial1 by which is usually understood loose gold in nuggets1 specks1 and dust1 lying in drifts which were once the beds of long extinct streams and rivers1 or possibly the moraines of glaciers1 as in ,new ,zealand4 ,further on the differences will be mentioned between alluvial and reef or lode gold1 for that there is a difference in origin in many occurrences1 is1 ,i think1 provable4 ,i hold1 and hold strongly1 that true alluvial gold is not always derived from the disintegration of lodes or reefs4 ,for instance1 the ,welcome ,nugget certainly never came from a reef4 ,no such mass of gold1 or anything approaching it1 has ever yet been taken from a quartz matrix4 ,it was found at ,bakery ,hill1 ,ballarat1 in #aheh1 weight #baie ozs41 and sold for #aj1ejj pounds4 ,this was above its actual value4 ,the ,welcome ,stranger1 a still larger mass of gold1 was found amongst the roots of a tree at ,dunolly1 ,victoria1 in #ahfi1 by two starved out fossickers named ,deeson and ,oates4 ,the weight of this1 the largest authenticated nugget ever found was #bbfh #a_/b ozs41 and it was sold for #aj1jjj pounds1 but it was rendered useless as a specimen by the finders1 who spent a night burning it to remove the adhering quartz4 ,but the ordinary digger neither hopes nor expects to unearth such treasures as these4 ,he is content to gather together by means of puddling machine1 cradle1 long tom1 or even puddling tub and tin dish1 the scales1 specks1 dust1 and occasional small nuggets ordinarily met with in alluvial washes4 ,having sunk to the wash1 or drift1 the digger1 by means of one or more of the appliances mentioned above1 proceeds to separate the gold from the clay and gravel in which it is found4 ,of course in large alluvial claims1 where capital is employed1 such appliances are superseded by steam puddles1 buddles1 and other machinery1 and sometimes mercury is used to amalgamate the gold when very fine4 ,hydraulicing is the cheapest form of alluvial mining1 but can only be profitably carried out where extensive drifts1 which can be worked as quarry faces1 and unlimited water exist in the same neighbourhood4 ,when such conditions obtain a few grains of gold to the yard or ton will pay handsomely4 ,lode or reef mining1 is a more expensive and complicated process1 requiring much skill and capital4 ,first1 let me explain what a lode really is4 ,the ,american term is ledge1 and it is not inappropriate or inexpressive4 ,imagine then a ledge1 or kerbstone1 continuing to unknown depths in the earth at any angle varying from perpendicular to nearly horizontal4 ,this kerbstone is totally distinct from the rocks which enclose it2 those on one side may be slate1 on the other1 sandstone2 but the lode1 separated usually by a small band of soft material known to miners as casing1 or fluccan1 preserves always an independent existence1 and in many instances is practically bottomless so far as human exploration is concerned4 ,there are1 however1 reefs or lodes which are not persistent in depth4 ,sometimes the lode formation is found only in the upper and newer strata1 and cuts out when1 say1 the basic rocks 7such as granite1 etc47 are reached4 ,again1 there is a form of lode known among miners as a gash vein4 ,it is sometimes met with in the older crystalline slates1 particularly when the lode runs conformably with the cleavage of the rock4 ,much ignorance is displayed on the subject of lode formation and the deposition of metals therein1 even by mining men of long experience4 ,many still insist that lodes1 particularly those containing gold1 are of igneous origin1 and point to the black and brown ferro-manganic outcrops in confirmation4 ,it must be admitted that often the upper portions of a lode present a strong appearance of fire agency1 but exactly the same appearance can be caused by oxidation of iron and manganese in water4 ,it may now be accepted as a proven fact that no true lode has been formed1 or its metals deposited except by aqueous action4 ,that is to say1 the bulk of the lode and all its metalliferous contents were once held in solution in subterranean waters1 which were ejected by geysers or simply filtered into fissures formed either by the shrinkage of the earth's crust in process of cooling or by volcanic force4 ,it is not contended that the effect of the internal fires had no influence on the formation of metalliferous veins1 indeed1 it is certain that they had1 but the action was what is termed hydrothermal 7hot water72 and such action we may see in progress to-day in ,new ,zealand1 where hot springs stream or spout above the surface1 when the silica and lime impregnated water1 reduced in heat and released from pressure1 begins forthwith to deposit the minerals previously held in solution4 ,hence the formation of the wondrous ,pink and ,white ,terrace1 destroyed by volcanic action some eight years since1 which grew almost while you watched2 so rapidly was the silica deposited that a dead beetle or ti-tree twig left in the translucent blue water for a few days became completely coated and petrified4 ,gold differs in its mode of occurrence from other metals in many respects2 but there is no doubt that it was once held in aqueous solution and deposited in its metallic form by electro-chemical action4 ,it is true we do not find oxides1 carbonates1 or bromides of gold in ,nature1 nor can we feel quite sure that gold now exists naturally as a sulphide1 chloride1 or silicate1 though the presumption is strongly that it does4 ,if so1 the deposition of the gold may be ceaselessly progressing4 ,generally reef gold is finer as to size of the particles1 and1 as a rule1 inferior in quality to alluvial4 ,thus1 in addition to the extra labor entailed in breaking into one of the hardest of rocks1 quartz1 the madre de oro 7mother of gold7 of the ,spaniards1 there is the additional labour required to pulverise the rock so as to set free the tiniest particles of the noble metal it so jealously guards4 ,there is also the additional difficult operation of saving and gathering together these small specks1 and so producing the massive cakes and bars of gold in their marketable state4 ,having found payable gold in quartz on the surface1 the would-be miner has next to ascertain two things4 ,first1 the strike or course of the lode2 and secondly1 its underlie1 or dip4 ,the strike1 or course1 is the direction which the lode takes lengthwise4 ,in ,australia the term underlie is used to designate the angle from the perpendicular at which the lode lies in its enclosing rocks1 and by dip the angle at which it dips or inclines lengthwise on its course4 ,thus1 at one point the cap of a lode may appear on the surface1 and some distance further the cap may be hundreds of feet below4 ,usually a shaft is sunk in the reef to prove the underlie1 and a level1 or levels1 driven on the course to ascertain its direction underground1 also if the gold extends1 and if so1 how far4 ,this being proved1 next a vertical shaft is sunk on the hanging or upper wall side1 and the reef is either tapped thereby1 or a cross-cut driven to intersect it4 ,we will now assume that our miners have found their lode payable1 and have some hundreds of tons of good gold-bearing stone in sight or at the surface4 ,they must next provide a reducing plant4 ,of means for crushing or triturating quartz there is no lack1 and every year gives us fresh inventions for the purpose1 each one better than that which preceded it1 according to its inventor4 ,most practical men1 however1 prefer to continue the use of the stamper battery1 which is virtually a pestle and mortar on a large scale4 ,why we adhere to this form of pulverising machine is that1 though somewhat wasteful of power1 it is easily understood1 its wearing parts are cheaply and expeditiously replaced1 and it is so strong that even the most perversely stupid workman cannot easily break it or put it out of order4 ,the stone1 being pounded into sand of such degree of fineness as the gold requires1 passes through a perforated iron plate called a grating1 or screen1 on to an inclined surface of copper plates faced with mercury1 having small troughs1 or riffles1 containing mercury1 placed at certain distances apart4 ,the crushed quartz is carried over these copper tables1 as they are termed1 thence over the blanket tables--that is1 inclined planes covered with coarse serge1 blankets1 or other flocculent material--so that the heavy particles may be caught in the hairs1 or is passed over vanners or concentrating machines4 ,the resulting concentrates are washed off from time to time and reserved for secondary treatment4 ,to begin with1 they are roasted to get rid of the sulphur1 arsenic1 etc41 which would interfere with the amalgamation or lixiviation1 and then either ground to impalpable fineness in one of the many triturating pans with mercury1 or treated by chlorine or potassium cyanide4 ,if1 however1 we are merely amalgamating1 then at stated periods the battery and pans are cleaned out1 the amalgam rubbed or scraped from the copper plates and raised from the troughs and riffles4 ,it is then squeezed through chamois leather1 or good calico will do as well1 and retorted in a large iron retort1 the nozzle of which is kept in water so as to convert the mercury vapour again to the metallic form4 ,the result is a spongy cake of gold1 which is either sold as retorted gold or smelted into bars4 ,the other and more scientific methods of extracting the precious metal from its matrices1 such as lixiviation or leaching1 by means of solvents 7chlorine1 cyanogen1 hyposulphite of soda1 etc471 will be more fully described later on4 ,,chapter ,,ii ,,gold ,,prospecting--,,alluvial ,,and ,,general ,it is purposed in this chapter to deal specially with the operation of searching for valuable mineral by individuals or small working parties4 ,it is well known that much disappointment and loss accrue through lack of knowledge by prospectors1 who with all their enterprise and energy are often very ignorant1 not only of the probable locality1 mode of occurrence1 and widely differing appearance of the various valuable minerals1 but also of the best means of locating and testing the ores when found4 ,it is for the information of such as these that this chapter is mainly intended1 not for scientists or miners of large experience4 ,all of us who have had much to do with mining know that the majority of the best mineral finds have been made by the purest accident2 often by men who had no mining knowledge whatever2 and that many valuable discoveries have been delayed1 or1 when made1 abandoned as not payable1 from the same cause--ignorance of the rudiments of mineralogy and mining4 ,i have frequently been asked by prospectors1 when inspecting new mineral fields1 what rudimentary knowledge will be most useful to them and how it can be best obtained4 ,if a man can spare the time a course of lessons at some accredited school of mines will be1 undoubtedly1 the best possible training2 but if he asks what books he should read in order to obtain some primary technical instruction1 ,i reply3 ,first1 an introductory text-book of geology1 which will tell him in the simplest and plainest language all he absolutely requires to know on this important subject4 ,every prospector should understand elementary geology so far as general knowledge of the history of the structure of the earth's crust and of the several actions that have taken place in the past1 or are now in operation1 modifying its conditions4 ,he may with advantage go a few steps further and learn to classify the various formations into systems1 groups1 and series3 but he can acquire all that he need absolutely know from this useful little #bs4 #f;d4 book4 ,next1 it is advisable to learn something about the occurrence and appearance of the valuable minerals and the formations in which they are found4 ,for all practical purposes ,i can recommend ,cox and ,ratte's ,mines and ,minerals1 one of the ,technical ,education series of ,new ,south ,wales1 which deals largely with the subject from an ,australian standpoint1 and is therefore particularly valuable to the ,australian miner1 but which will be found applicable to most other gold-bearing countries4 ,i must not1 however1 omit to mention an admirably compiled multum in parvo volume prepared by ,mr4 ,g4 ,goyder1 jun41 ,government ,assayer and ,assay ,instructor at the ,school of ,mines1 ,adelaide4 ,it is called the ,prospectors' ,pocketbook1 costs only one shilling1 is well bound1 and of handy size to carry4 ,in brief1 plain language it describes how a man1 having learned a little of assaying1 may cheaply provide himself with a portable assay plant1 and fluxes1 and also gives considerable general information on the subject of minerals1 their occurrence and treatment499 99 ,another excellent and really practical book is ,prof4 ,cole's ,practical ,aids in ,geology 7second edition71 #ajs4 #f;d4 ,it may here be stated that some twelve years ago ,i did a large amount of practical silver assaying on the ,barrier 7,broken ,hill71 which was not then so accessible a place as it is now1 and got closely correct results from a number of different mines1 with an extemporised plant almost amusing in its simplicity4 ,all ,i took from ,adelaide were a small set of scales capable of determining the weight of a button down to #bj ozs4 to the ton1 a piece of cheese cloth to make a screen or sieve1 a tin ring #a #a_/b in4 diameter1 by #a_/b in4 high1 a small brass door knob to use as a cupel mould1 and some powdered borax1 carbonate of soda1 and argol for fluxes2 while for reducing lead ,i had recourse to the lining of a tea-chest1 which lead contains no silver--,john ,chinaman takes good care of that4 ,my mortar was a jam tin1 without top or bottom1 placed on an anvil2 the pestle a short steel drill4 ,the blacksmith at ,mundi ,mundi ,station made me a small wrought iron crucible1 also a pair of bent tongs from a piece of fencing-wire4 ,the manager gave me a small common red flower pot for a muffle1 and with the smith's forge 7the fire built round with a few blocks of talcose schist7 for a furnace1 my plant was complete4 ,i burned and crushed bones to make my bone-dust for cupelling1 and thus provided made nearly forty assays1 some of which were afterwards checked in ,adelaide1 in each instance coming as close as check assays generally do4 ,nowadays one can purchase cheaply a very effective portable plant1 or after a few lessons a man may by practice make himself so proficient with the blowpipe as to obtain assay results sufficiently accurate for most practical purposes4 ,coming then to the actual work of prospecting4 ,what the prospector requires to know is1 first1 the usual locality of occurrence of the more valuable minerals2 secondly1 their appearance2 thirdly1 a simple mode of testing4 ,with respect to occurrence1 the older sandy and clay slates1 chlorite slates1 micaceous1 and hornblendic schists1 particularly at or near their junction with the intrusive granite and diorite1 generally form the most likely geological country for the finding of mineral lodes1 particularly gold1 silver and tin4 ,but those who have been engaged in practical mining for long1 finding by experience that no two mineral fields are exactly alike in all their characteristics1 have come to the conclusion that it is unwise to form theories as to why metals should or should not be found in certain enclosing rocks or matrices4 ,some of the best reef gold got in ,victoria has been obtained in dead white1 milky-looking quartz almost destitute of base metal4 ,in ,south ,australia reef gold is almost invariably associated with iron1 either as oxide1 as gossan2 or ferruginous calcite1 limonite2 or granular silica1 conglomerated by iron1 the ironstone which forms the capping or outcrop of many of our reefs1 and which is often rich in gold4 ,but to show that it is unsafe to decide off-hand in what class of matrix metals will or will not be found1 ,i may say that in my own experience ,i have seen payable gold in the following materials3-- ,quartz1 dense and milky1 also in quartz of nearly every colour and appearance1 saccharoidal1 crystalline1 nay1 even in clear glass-like six-sided prismatic crystals1 and associated with silver1 copper1 lead1 arsenic1 iron as sulphide1 oxide1 carbonate1 and tungstate1 antimony1 bismuth1 nickel1 zinc1 lead1 and other metals in one form or another2 in slate1 quartzite1 mica schist1 granite1 diorite1 porphyry1 felsite1 calcite1 dolomite1 common carbonate of iron1 siliceous sinter from a hot spring1 as at ,mount ,morgan2 as alluvial gold in drifts formed of almost all these materials2 and once1 perhaps the most curious matrix of all1 a small piece of apparently alluvial gold1 naturally imbedded in a shaly piece of coal4 ,this specimen1 ,i think1 is in the ,sydney ,museum4 ,one thing1 however1 the prospector may make sure of3 he will always find gold more or less intimately associated with silica 7,quartz7 in one or other of its many forms1 just as he will always find cassiterite 7oxide of tin7 in the neighbourhood of granite containing muscovite 7white mica71 which so many people will persist in terming talc4 ,it is stated to be a fact that tin has never been found more than about two miles from such granite4 ,from what has been said of its widely divergent occurrences it will be admitted that the ,cornish miners' saying with regard to metals generally applies with great force to gold3 ,where it is1 there it is3 and ,cousin ,jack adds1 with pathetic emphasis1 and where it is generally1 there ,i ain't4 ,i have already spoken of the geological country rock in which red gold is most likely to be discovered--i4e41 the junction of the slates and schists with the igneous or metamorphic 7altered7 rocks1 or in this vicinity4 ,old river beds formed of gravelly drifts in the same neighbourhood may probably contain alluvial gold1 or shallow deposits of wash on hillsides and in valleys will often carry good surface gold4 ,this is sometimes due to the denudation1 or wearing away1 of the hills containing quartz-veins--that is1 where the alluvial gold really was derived from such veins1 which1 popular opinion to the contrary1 is not always the case4 ,much disappointment and loss of time and money may sometimes be prevented if prospectors will realise that all alluvial gold does not come from the quartz veins or reefs2 and that following up an alluvial lead1 no matter how rich1 will not inevitably develop a payable gold lode4 ,sometimes gold1 evidently of reef origin1 is found in the alluvial2 but in that case it is generally fine as regards the size of the particles1 more or less sharp-edged1 or crystalline in form if recently shed2 while such gold is often of poorer quality than the true alluvial which occurs in mammillary 7breast-like7 nuggets1 and is of a higher degree of purity as gold4 ,the ordinary non-scientific digger will do well to give credence to this view of the case1 and will often thereby save himself much useless trouble4 ,sometimes also the alluvial gold1 coarser in size than true reef-born alluvial1 is derived almost in situ from small quartz leaders1 or veins1 which the grinding down of the face of the slates has exposed2 these leaders in time being also broken and worn1 set free the gold they have contained1 which does not1 as a rule1 travel far1 but sometimes becomes water-worn by the rubbing over it of the disintegrated fragments of rock4 ,but the heavy1 true alluvial gold1 in great pure masses1 mammillary1 or botryoidal 7like a bunch of grapes7 in shape1 have assuredly been formed by accretion on some metallic base1 from gold salts in solution1 probably chloride1 but possibly sulphide4 ,nuggets1 properly so-called1 are never found in quartz lodes2 but1 as will be shown later1 a true nugget having all the characteristics of so-called water-worn alluvial may be artificially formed on a small piece of galena1 or pyrites1 by simply suspending the base metal by a thread in a vessel containing a weak solution of chloride of gold in which a few hard-wood chips are thrown4 ,prospecting for alluvial gold at shallow depths is a comparatively easy process1 requiring no great amount of technical knowledge4 ,usually the first gold is got at or near the surface and then traced to deep leads1 if such exist4 ,at ,mount ,brown ,goldfield1 ,n4,s4,w41 in #ahha1 ,i saw claimholders turning out to work equipped only with a small broom made of twigs and a tin dish4 ,with the broom they carefully swept out the crevices of the decomposed slate as it was exposed on the surface1 and putting the resulting dust and fragments into the tin dish proceeded to dry blow it4 ,the modus operandi is as follows3 ,the operator takes the dish about half full of dirt1 and standing with his back or side to the wind1 if there be any1 begins throwing the stuff up and catching it1 or sometimes slowly pouring it from one dish to another1 the wind in either case carrying away the finer particles4 ,he then proceeds to reduce the quantity by carefully extracting the larger fragments of rock1 till eventually he has only a handful or so of moderately fine dirt which contains any gold there may be4 ,if in good sized nuggets it is picked out1 if in smaller pieces or fine grains the digger slowly blows the sand and dust aside with his breath1 leaving the gold exposed4 ,this process is both tedious and unhealthy1 and of course can only be carried out with very dry surface dirt4 ,the stuff in which the gold occurred at ,mount ,brown was composed of broken slate with a few angular fragments of quartz4 ,yet1 strange to say1 the gold was invariably waterworn in appearance4 ,dry blowing is now much in vogue on the ,west ,australian fields owing to the scarcity of water2 but the great objection is first1 the large amount of dust the unfortunate dry blower has to carry about his person1 and secondly1 that the peck of dirt which is supposed to last most men a life time has to be made a continuous meal of every day4 ,for wet alluvial prospecting the appliances1 besides pick and shovel1 are puddling tub1 tin dish1 and cradle2 the latter1 a man handy with tools can easily make for himself4 ,in sinking1 the digger should be careful to avoid making his shaft inconveniently small1 and not to waste his energy by sinking a large new chum hole1 which usually starts by being about three times too large for the requirements at the surface1 but narrows in like a funnel at #aj feet or less4 ,a shaft1 say #d feet by #b feet #f inches and sunk plumb1 the ends being half rounded1 is large enough for all requirements to a considerable depth1 though ,i have seen smart men1 when they were in a hurry to reach the drift1 get down in a shaft even less in size4 ,the novice who is trying to follow or to find a deep lead must fully understand that the present bed of the surface river may not1 in fact seldom does1 indicate the ancient watercourses long since buried either by volcanic or diluvial action1 which contain the rich auriferous deposits for which he is seeking2 and much judgment and considerable underground exploration are often required to decide on the true course of leads4 ,only by a careful consideration of all the geological surroundings can an approximate idea be obtained from surface inspection alone2 and the whole probable conditions which led to the present contour of the country must be carefully taken into account4 ,how am ,i to know the true bottom when ,i see it8 asks the inexperienced digger4 ,well1 nothing but long experience and intelligent observation will prevent mistakes at times1 particularly in deep ground2 but as a general rule1 though it may sound paradoxical1 you may know the bottom by the top4 ,that is1 we will assume you are sinking in1 say1 #aj to #ab feet ground in a gully on the bank of which the country rock is exposed1 and is1 say1 for instance1 a clay slate or sandy slate set at a certain angle2 then1 in all probability1 unless there be a distinct fault or change in the country rock between the slate outcrop and your shaft1 the bottom will be a similar slate1 standing at the same angle2 and this will very probably be overlaid by a deposit of pipeclay1 formed by the decomposition of the slates4 ,from the crevices of these slates1 sometimes penetrating to a considerable distance1 you may get gold1 but it is useless attempting to sink through them4 ,if the outcropping strata be a soft calcareous 7limy7 sandstone or soft felspathic rock1 and that be also the true bottom1 great care should be exercised or one is apt to sink through the bottom1 which may be very loose and decomposed4 ,i have known mistakes made in this way when many feet have been sunk1 and driven through what was actually bed rock1 though so soft as to deceive even men of experience4 ,the formation1 however1 must be the guide1 and except in some specially difficult cases1 a man can soon tell when he is really on bed rock or bottom4 ,on an alluvial lead the object of every one is to get on the gutter1 that is1 to reach the lowest part of the old underground watercourse1 through which for centuries the gold may have been accretionising from the percolation of the mineral-impregnated water2 or1 when derived from reefs or broken down leaders1 the flow of water has acted as a natural sluice wherein the gold is therefore most thickly collected4 ,sometimes the lead runs for miles and is of considerable width1 at others it is irregular1 and the gold-bearing gutter small and hard to find4 ,in many instances1 for reasons not readily apparent1 the best gold is not found exactly at the lowest portion of these narrow gutters1 but a little way up the sides4 ,this fact should be taken into consideration in prospecting new ground1 for many times a claim has been deserted after cleaning up the bottom1 and another man has got far better gold considerably higher up on the sides of the gutter4 ,for shallow alluvial deposits1 where a man quickly works out his #cj by #cj feet claim1 it may be cheaper at times to paddock the whole ground--that is1 take all away from surface to bottom1 but if he is in wet ground and he has to drive1 great care should be taken to properly secure the roof by means of timber4 ,how this may best be done the local circumstances only can decide4 ,,chapter ,,iii ,,lode ,,or ,,reef ,,prospecting ,the preceding chapter dealt more especially with prospecting as carried on in alluvial fields4 ,i shall now treat of preliminary mining on lodes or reefs4 ,as has already been stated1 the likeliest localities for the occurrence of metalliferous deposits are at or near the junction of the older sedimentary formations with the igneous or intrusive rocks1 such as granites1 diorites1 etc4 ,in searching for payable lodes1 whether of gold1 silver1 copper1 or even tin in some forms of occurrence1 the indications are often very similar4 ,the first prospecting is usually done on the hilltops or ridges1 because1 owing to denudation by ice or water which have bared the bedrock1 the outcrops are there more exposed1 and thence the lodes are followed down through the alluvial covered plains1 partly by their strike or trend1 and sometimes by other indicating evidences1 which the practical miner has learned to know4 ,for instance1 a lesson in tracing the lode in a grass covered country was taught me many years ago by an old prospector who had struck good gold in the reef at a point some distance to the east of what had been considered the true course4 ,i asked him why he had opened the ground in that particular place4 ,said he1 ,some folks don't use their eyes4 ,you stand here and look towards that claim on the rise where the reef was last struck4 ,now1 don't you see there is almost a track betwixt here and there where the grass and herbage is more withered than on either side8 ,why8 ,well1 because the hard quartz lode is close to the surface all the way1 and there is no great depth of soil to hold the moisture and make the grass grow4 ,i have found this simple lesson in practical prospecting of use since4 ,but the strike or course of a quartz reef is more often indicated by outcrops1 either of the silica itself or ironstone blows1 as the miners call them1 but the term is a misnomer1 as it argues the easily disproved igneous theory of veins of ejection1 meaning thereby that the quartz with its metalliferous contents was thrown out in a molten state from the interior of the earth4 ,this has in no case occurred1 and the theory is an impossible one4 ,true lodes are veins of injection formed by the infiltration of silicated waters carrying the metals also in solution4 ,this water filled the fissures caused either by the cooling of the earth's crust1 or formed by sudden upheavals of the igneous rocks4 ,sometimes in alluvial ground the trend of the reef will be revealed by a track of quartz fragments1 more or less thickly distributed on the surface and through the superincumbent soil4 ,follow these along1 and at some point1 if the lode be continuous1 a portion of its solid mass will generally be found to protrude and can then again be prospected4 ,there is no rule as to the trend or strike of lodes1 except that a greater number are found taking a northerly and southerly course than one which is easterly and westerly4 ,at all events1 such is the case in ,australia1 but it cannot be said that either has the advantage in being more productive4 ,some of the richest mines in ,australasia have been in lodes running easterly and westerly1 while gold1 tin1 and copper1 in great quantity and of high percentage to the ton1 have been got in such mines as ,mount ,morgan1 ,mount ,bischoff1 and the ,burra1 where there are no lodes properly so-called at all4 ,mount ,morgan is the richest and most productive gold mine in ,australasia and amongst the best in the world4 ,its yield for #ahie was #abh1fii oz4 of gold1 valued at #ebh1gjj pounds4 ,dividends paid in #ahie1 #cjj1jjj pounds4 ,this mine was opened in #ahhf4 ,up to ,may #ca1 #ahig1 the total yield was #a1fca1iha ozs4 of gold1 sold at #f1gab1ahg pounds1 from which #d1djj1jjj pounds have been paid in dividends4 7,see ,mining ,journal1 for ,oct4 #i1 #ahig47 ,mount ,morgan shareholders have1 in other words1 divided over #dc #a_/b tons of standard gold4 ,the ,burra ,burra ,mine1 about #ajj miles from ,adelaide1 in a direction a little to the east of north1 was found in #ahde by a shepherd named ,pickett4 ,it is singularly situated on bald hills standing #acj feet above the surrounding country4 ,the ores obtained from this copper mine had been chiefly red oxides1 very rich blue and green carbonates1 including malachite1 and also native copper4 ,the discovery of this mine1 supporting1 as it did at one time1 a large population1 marked a new era in the history of the colony4 ,the capital invested in it was #ab1cbj pounds in #e pound shares1 and no subsequent call was ever made upon the shareholders4 ,the total amount paid in dividends was #hjj1jjj pounds4 ,after being worked by the original owners for some years the mine was sold to a new company1 but during the last few years it has not been worked1 owing in some degree to the low price of copper and also to the fact that the deposit then being worked apparently became exhausted4 ,for many years the average yield was from #aj1jjj to #ac1jjj tons of ore1 averaging #bb to #bc per cent of copper4 ,it is stated that1 during the twenty-nine and a half years in which the mine was worked1 the company expended #b1bda1afg in general expenses4 ,the output of ore during the same period amounted to #bcd1fdh tons1 equal to #ea1fbb tons of copper4 ,this1 at the average price of copper1 amounted to a money value of #d1gdi1bbd pounds4 ,the mine stopped working in #ahgg4 ,mount ,bischoff1 ,tasmania1 has produced1 since the formation of the ,company to ,december #ahie1 #dg1bfc tons of tin ore4 ,it is still in full work and likely to be for years to come4 ,each of these immense metalliferous deposits was found outcropping on the summit of a hill of comparatively low altitude4 ,there are no true walls nor can the ore be traced away from the hill in lode form4 ,these occurrences are generally held to be due to hydrothermal or geyser action4 ,then again lodes are often very erratic in their course4 ,slides and faults throw them far from their true line1 and sometimes the lode is represented by a number of lenticular 7double-pointed in section7 masses of quartz of greater or less length1 either continuing point to point or overlapping1 splicing1 as the miners call it4 ,such formations are very common in ,west ,australia4 ,all this has to be considered and taken into account when tracing the run of stone4 ,this tyro also must carefully remember that in rough country where the lode strikes across hills and valleys1 the line of the cap or outcrop will apparently be very sinuous owing to the rises and depressions of the surface4 ,many people even now do not understand that true lodes or reefs are portions of rock or material differing from the surrounding and enclosing strata1 and continuing down to unknown depths at varying angles4 ,therefore1 if you have a north and south lode outcropping on a hill and crossing an east and west valley1 the said lode1 underlying east1 when you have traced its outcrop to the lowest point in the valley1 between the two hills1 will be found to be a greater or less distance1 according to the angle of its dip or underlie1 to the east of the outcrop on the hill where it was first seen4 ,if it be followed up the next hill it will come again to the west1 the amount of apparent deviation being regulated by the height of the hills and depth of the valley4 ,a simple demonstration will make this plain4 ,take a piece of half-inch pine board1 #b ft4 long and #i in4 wide1 and imagine this to be a lode2 now cut a half circle out of it from the upper edge with a fret saw and lean the board say at an angle of #de degrees to the left1 look along the top edge1 which you are to consider as the outcrop on the high ground1 the bottom of the cut being the outcrop in the valley1 and it will be seen that the lowest portion of the cut is some inches to the right2 so it is with the lode1 and in rough country very nice judgment is required to trace the true course4 ,for indications1 never pass an ironstone blow without examination4 ,remember the pregnant ,cornish saying with regard to mining and the current aphorism1 ,the iron hat covers the golden head4 ,cousin ,jack1 put it ,iron rides a good horse4 ,the ironstone outcrop may cover a gold1 silver1 copper or tin lode4 ,if you are searching for gold1 the presence of the royal metal should be apparent on trial with the pestle and mortar2 if silver1 either by sight in one of its various forms or by assay1 blowpipe or otherwise2 copper will reveal itself by its peculiar colour1 green or blue carbonates1 red oxides1 or metallic copper4 ,it is an easy metal to prospect for1 and its percentage is not difficult to determine approximately4 ,tin is more difficult to identify1 as it varies so greatly in appearance4 ,having found your lode and ascertained its course1 you want next to ascertain its value4 ,as a rule 7and one which it will be well to remember7 if you cannot find payable metal1 particularly in gold reef prospecting1 at or near the surface1 it is not worth while to sink1 unless1 of course1 you design to strike a shoot of metal which some one has prospected before you4 ,the idea is exploded that auriferous lodes necessarily improve in value with depth4 ,the fact is that the metal in any lode is not1 as a rule1 equally continuous in any direction1 but occurs in shoots dipping at various angles in the length of the lode1 in bunches or sometimes in horizontal layers4 ,nothing but actual exploiting with pick1 powder1 and brains1 particularly brains1 will determine this point4 ,where there are several parallel lodes and a rich shoot has been found in one and the length of the payable ore ascertained1 the neighbouring lodes should be carefully prospected opposite to the rich spot1 as often similar valuable deposits will thus be found4 ,having ascertained that you have1 say1 a gold reef payable at surface and for a reasonable distance along its course1 you next want to ascertain its underlie or dip1 and how far the payable gold goes down4 ,as a general rule in many parts of ,australia--though by no means an inflexible rule--a reef running east of north and west of south will underlie east2 if west of north and east of south it will go down to the westward and so round the points of the compass till you come to east and west2 when if the strike of the lodes in the neighbourhood has come round from north-east to east and west the underlie will be to the south2 if the contrary was the case1 to the north4 ,it is surprising how often this mode of occurrence will be found to obtain4 ,but ,i cannot too strongly caution the prospector not to trust to theory but to prove his lode and his metal by following it down on the underlie4 ,stick to your gold is an excellent motto4 ,as a general thing it is only when the lode has been proved by an underlie shaft to water level and explored by driving on its course for a reasonable distance that one need begin to think of vertical shafts and the scientific laying out of the mine4 ,a first prospecting shaft need not usually be more than #e ft4 by #c ft4 or even #e ft4 by #b ft4 #f in41 particularly in dry country4 ,one may often see in hard country stupid fellows wasting time1 labour1 and explosives in sinking huge excavations as much as #aj ft4 by #h ft4 in solid rock1 sometimes following down #f inches of quartz4 ,when your shaft is sunk a few feet1 you should begin to log up the top for at least #c ft4 or #d ft41 so as to get a tip for your mullock and lode stuff4 ,this is done by getting a number of logs1 say #f inches diameter1 lay one #g ft4 log on each side of your shaft1 cut two notches in it #f ft4 apart opposite the ends of the shaft1 lay across it a #e ft4 log similarly notched1 so making a frame like a large ,oxford picture frame4 ,continue this by piling one set above another till the desired height is attained1 and on the top construct a rough platform and erect your windlass4 ,if you have an iron handle and axle ,i need not tell you how to set up a windlass1 but where timber is scarce you may put together the winding appliance described in the chapter headed ,rules of ,thumb4 ,if you have struck it rich you will have the pleasure of seeing your primitive windlass grow to a whip1 a whim1 and eventually to a big powerful engine1 with its huge drum and ,eiffel tower-like poppet heads1 or derrick1 with their great spindle pulley wheels revolving at dizzy speed high in air4 ,how shall ,i know if ,i have payable gold so as to save time and trouble in sinking8 says the novice4 ,truly it is a most important part of the prospector's art1 whether he be searching for alluvial or reef gold1 stream or lode tin1 copper1 or other valuable metal4 ,i presume you know gold when you see it8 ,if you don't1 and the doubtful particle is coarse enough1 take a needle and stick the point into the questionable specimen4 ,if gold the steel point will readily prick it2 if pyrites or yellow mica the point will glance off or only scratch it4 ,the great importance of the first prospect from the reef is well shown by the breathless intensity with which the two bearded1 bronzed pioneer prospectors in some trackless ,australian wild bend over the pan in which the senior mate is slowly reducing the sample of powdered lode stuff4 ,how eagerly they examine the last pinch of black sand in the corner of the dish4 ,prosperity and easy times1 or poverty and more hard graft shall shortly be revealed in the last dexterous turn of the pan4 ,let us hope it is a pay prospect4 ,the learner1 if he be far afield and without appliances of any kind1 can only guess his prospect4 ,an old prospector will judge from six ounces of stuff within a few pennyweights what will be the yield of a ton4 ,i have seen many a good prospect broken with the head of a pick and panned in a shovel1 but for reef prospecting you should have a pestle and mortar4 ,the handiest for travelling is a mortar made from a mercury bottle cut in half1 and a not too heavy wrought iron pestle with a hardened face4 ,to be particular you require a fine screen in order to get your stuff to regulated fineness4 ,the best for the prospector1 who is often on the move1 is made from a piece of cheesecloth stretched over a small hoop4 ,if you would be more particular take a small spring balance or an improvised scale1 such as is described in ,mr4 ,goyder's excellent little book1 p4 #ad1 which will enable you to weigh down to one-thousandth of a grain4 ,it is often desirable to burn your stone before crushing1 as it is thus more easily triturated and will reveal all its gold2 but remember1 that if it originally contained much pyrites1 unless a similar course is adopted when treated in the battery1 some of the gold will be lost in the pyrites4 ,having crushed your gangue to a fine powder you proceed to pan it off in a similar manner to that of washing out alluvial earth1 except that in prospecting quartz one has to be much more particular1 as the gold is usually finer4 ,the pan is taken in both hands1 and enough water to cover the prospect by a few inches is admitted4 ,the whole is then swirled round1 and the dirty water poured off from time to time till the residue is clean quartz sand and heavy metal4 ,then the pan is gently tipped1 and a side to side motion is given to it1 thus causing the heavier contents to settle down in the corner4 ,next the water is carefully lapped in over the side1 the pan being now tilted at a greater angle until the lighter particles are all washed away4 ,the pan is then once more righted1 and very little water is passed over the pinch of heavy mineral a few times1 when the gold will be revealed in a streak along the bottom4 ,in this operation1 as in all others1 only practice will make perfect1 and a few practical lessons are worth whole pages of written instruction4 ,to make an amalgamating assay that will prove the amount of gold which can be got from a ton of your lode1 take a number of samples from different parts1 both length and breadth4 ,the drillings from the blasting bore-holes collected make the best test4 ,when finely triturated weigh off one or two pounds1 place in a black iron pan 7it must not be tinned71 with #d ozs4 of mercury1 #d ozs4 salt1 #d ozs4 soda1 and about half a gallon of boiling water2 then1 with a stick1 stir the pulp constantly1 occasionally swirling the dish as in panning off1 till you feel certain that every particle of the gangue has come in contact with the mercury2 then carefully pan off into another dish so as to lose no mercury4 ,having got your amalgam clean squeeze it through a piece of chamois leather1 though a good quality of new calico previously wetted will do as well4 ,the resulting pill of hard amalgam can then be wrapped in a piece of brown paper1 placed on an old shovel1 and the mercury driven off over a hot fire2 or a clay tobacco pipe1 the mouth being stopped with clay1 makes a good retort 7see ,rules of ,thumb1 pipe and potato retorting74 ,the residue will be retorted gold1 which1 on being weighed and the result multiplied by #bbdj for a #a lb4 assay1 or by #aabj for #b lb41 will give the amount of gold per ton which an ordinary battery might be expected to save4 ,thus #a grain to the pound1 #bbdj lbs4 to the ton1 would show that the stuff contained #d oz4 #ac dwt4 #h gr4 per ton4 ,if there should be much base metal in your sample such as say stibnite 7sulphide of antimony71 a most troublesome combination to the amalgamator--instead of the formula mentioned above add to your mercury about one dwt4 of zinc shavings or clippings1 and to your water sufficient sulphuric acid to bring it to about the strength of vinegar 7weaker1 if anything1 not stronger71 place your material preferably in an earthenware or enamelled basin if procurable1 but iron will do1 and intimately mix by stirring and shaking till all particles have had an opportunity to combine with the mercury4 ,retort as before described4 ,this device is my own invention4 ,the only genuine test after all is the battery1 and that1 owing to various causes1 is often by no means satisfactory4 ,first1 there is a strong1 almost unconquerable temptation to select the stone1 thus making the testing of a few tons give an unduly high average2 but more often the trouble is the other way4 ,the stuff is sent to be treated at some inefficient battery with worn-out boxes1 shaky foundations1 and uneven tables1 sometimes with the plates not half amalgamated1 or coated with impurities1 the whole concern superintended by a man who knows as little about the treatment of auriferous quartz by the amalgamating or any other processes as a dingo does of the differential calculus4 ,result3 #c dwt4 to the ton in the retort1 #cj dwt4 in the tailings1 and a payable claim declared a duffer4 ,when the lode is really rich1 particularly if it be carrying coarse gold1 and owing to rough country1 or distance1 a good battery is not available1 excellent results in a small way may be obtained by the somewhat laborious1 but simple1 process of dollying4 ,a dolly is a one man power single stamp battery1 or rather an extra sized pestle and mortar 7see ,rules of ,thumb74 ,silver lodes and lodes which frequently carry more or less gold1 are often found beneath the dark ironstone blows1 composed of conglomerates held together by ferric and manganic oxides2 or1 where the ore is galena1 the surface indications will frequently be a whitish limey track sometimes extending for miles1 and nodules or slugs of that ore will generally be found on the surface from place to place4 ,most silver ores are easily recognisable1 and readily tested by means of the blowpipe or simple fire assay4 ,sometimes the silver on being tested is found to contain a considerable percentage of gold as in the great ,comstock lode in ,nevada4 ,ore from the big ,broken ,hill silver load1 ,new ,south ,wales1 also contains an appreciable quantity of the more precious metal4 ,a natural alloy of gold containing #bj per cent silver1 termed electrum1 is the lowest grade of the noble metal4 ,tin1 lode1 and stream1 or alluvial1 occurs only as an oxide1 termed cassiterite1 and yet you can well appreciate the compliment one ,cornish miner pays to another whose cleverness he wishes to commend1 when he says of him1 ,aw1 he do know tin1 when you look at a representative collection of tin ores4 ,in various shapes1 from sharp-edged crystals to mammillary-shaped nuggets of wood-tin2 from masses of #cj lbs4 weight to a fine sand1 like gunpowder1 in colour black1 brown1 grey1 yellow1 red1 ruby1 white1 and sometimes a mingling of several colours1 it does require much judgment to know tin4 ,stream tin is generally associated with alluvial gold4 ,when such is the case there is no difficulty in saving the gold if you save the tin1 for the yellow metal is of much greater specific gravity4 ,as the natural tin is an oxide1 and therefore not susceptible to amalgamation1 the gold can be readily separated by means of mercury4 ,lode tin sometimes occurs in similar quartz veins to those in which gold is got1 and is occasionally associated with gold4 ,tin is also found1 as at ,eurieowie1 in dykes1 composed of quartz crystals and large scales of white mica1 traversing the older slates4 ,a similar occurrence takes place at ,mount ,shoobridge and at ,bynoe ,harbour1 in the ,northern ,territory of ,south ,australia2 indeed1 one could not readily separate the stone from these three places if it were mixed4 ,as before stated tin will never be found far from granite1 and that granite must have white mica as one of its constituents4 ,it is seldom found in the darker coloured rocks1 or in limestone country1 but it sometimes occurs in gneiss1 mica schist1 and chlorite schist4 ,numerous other minerals are at times mistaken for tin1 the most common of which are tourmaline or schorl1 garnet1 wolfram 7which is a tungstate of iron with manganese71 rutile or titanic acid1 blackjack or zinc blende1 together with magnetic1 titanic1 and specular iron in fine grains4 ,this rough and ready mode of determining whether the ore is tin is by weight and by scratching or crushing1 when1 what is called the streak is obtained4 ,the colour of the tin streak is whitey-grey1 which1 when once known1 is not easily mistaken4 ,the specific gravity is about #g4j4 ,wolfram1 which is most like it1 is a little heavier1 from #g4j to #g4e1 but its streak is red1 brown1 or blackish-brown4 ,rutile is much lighter1 #d4b1 and the streak light-brown2 tourmaline is only #c4b4 ,blackjack is #d4c1 and its streak yellowish-white4 ,i have seen several pounds weight to the dish got in some of the ,new ,south ,wales shallow sinking tin-fields1 and1 as a rule1 payable gold was also present4 ,fourteen years ago ,i told ,western ,australian people1 when on a visit to that colony1 that the neighbourhood of the ,darling range would produce rich tin4 ,lately this had been proved to be the case1 and ,i look forward to a great development of the tin mining industry in the south-western portion of ,westralia4 ,the tin wash in question may also contain gold1 as the country rock of the neighbourhood is such as gold is usually found in499 99 ,since this book was in the printers' hands1 the discovery of payable gold has been reported from this district4 ,a detailed discussion of methods of prospecting will be found in chapter ii4 ,of ,le ,neve ,foster's ,ore and ,stone ,mining1 and ,mr4 ,s4 ,herbert ,cox's ,handbook for ,prospectors4 ,,chapter ,,iv ,,the ,,genesiology ,,of ,,gold--,,auriferous ,,lodes ,up to a comparatively recent time it was considered heretical for any one to advance the theory that gold had been deposited where found by any other agency than that of fire4 ,as late as #ahfj ,mr4 ,henry ,rosales convinced himself1 and apparently the ,victorian ,government also1 that quartz veins with their enclosed metal had been ejected from the interior of the earth in a molten state4 ,his essay1 which is very ingenious and cleverly written1 obtained a prize which the ,government had offered1 but probably ,mr4 ,rosales himself would not adduce the same arguments in support of the volcanic or igneous theory to-day4 ,his phraseology is very technical2 so much so that the ordinary inquirer will find it somewhat difficult to follow his reasoning or understand his arguments1 which have apparently been founded only on the occurrence of gold in some of the earlier discovered quartz lodes1 and the conclusions at which he arrived are not borne out by later experience4 ,he says3--,while1 however1 there are not apparent signs of mechanical disturbances1 during the long period that elapsed from the cooling of the earth's surface to the deposition of the ,silurian and ,cambrian systems1 it is to be presumed that the internal igneous activity of the earth's crust was in full force1 so that on the inner side of it1 in obedience to the laws of specific gravity1 chemical attraction1 and centrifugal force1 a great segregation of silica in a molten state took place4 ,this molten silica continually accumulating1 spreading1 and pressing against the horizontal ,cambro-,silurian beds during a long period at length forced its way through the superincumbent strata in all directions2 and it is abundantly evident1 under the conditions of this force and the resistance offered to its action1 that the line it would and must choose would be along any continuous and slightly inclined diagonal1 at times crossing the strata of the schists1 though generally preferring to develop itself and egress between the cleavage planes and dividing seams of the different schistose beds4 ,he goes on to say1 ,another argument to the same end 7i4e41 the igneous origin7 may be shown from the fact that the auriferous quartz lodes have exercised a manifest metamorphic action on the adjacent walls or casing2 they have done so partly in a mineralogical sense1 but generally there has been a metamorphic alteration of the rock4 ,mr4 ,rosales then tells his readers1 what we all know must be the case1 that the gold would be volatilised by the heat1 as would be also the other metals1 which he says1 were in the form of arseniurets and sulphurets2 but he fails to explain how the sublimated metals afterwards reassumed their metallic form4 ,seeing that1 in most cases1 they would be hermetically enclosed in molten and quickly solidifying silica they could not be acted on to any great extent by aqueous agency4 ,neither does ,mr4 ,rosales's theory account at all for auriferous lodes2 which below water level are composed of a solid mass of sulphide of iron with traces of other sulphides1 gold1 calcspar1 and a comparatively small percentage of silica4 ,nor will it satisfactorily explain the auriferous antimonial silica veins of the ,new ,england district1 ,new ,south ,wales1 in which quantities of angular and unaltered fragments of slate from the enclosing rocks are found imbedded in the quartz4 ,with respect to the metamorphism of the enclosing rocks to a greater degree of hardness1 which ,mr4 ,rosales considered was due to heat1 it should be remembered that these rocks in their original state were much softer and more readily fusible than the quartz1 consequently all would have been molten and mingled together instead of showing as a rule clearly defined walls4 ,it is much more rational to suppose that the increased hardness imparted to the slates and schists at or near their contact with the lode is due to an infiltration of silica from the silicated solution which at one time filled the fissure4 ,few scientists can now be found to advance the purely igneous theory of lode formation1 though it must be admitted that volcanic action has probably had much influence not only in the formation of mineral veins1 but also on the occurrence of the minerals therein4 ,but the action was hydrothermal1 just such as was seen in course of operation in ,new ,zealand a few years ago when1 in the ,rotomahana district1 one could actually see the growing of the marvellous ,white and ,pink ,terraces formed by the release of silica from the boiling water exuding from the hot springs1 which water1 so soon as the heat and pressure were removed1 began to deposit its silica very rapidly2 while at the ,thames ,gold-field1 in the same country hot1 silicated water continuously boiled out of the walls of some of the lodes after the quartz had been removed and re-deposited a siliceous sinter thereon4 ,on this subject ,i note the recently published opinions of ,professor ,lobley1 a gentleman whose scientific reputation entitles his utterances to respect1 but who1 when he contends that gold is not found in the products of volcanic action is1 ,i venture to think1 arguing from insufficient premises4 ,certainly his theories do not hold good either in ,australasia or ,america where gold is often1 nay1 more usually1 found at1 or near1 either present or past regions of volcanic action4 ,it is always gratifying to have one's theories confirmed by men whose opinions carry weight in the scientific world4 ,about seventeen years ago ,i first published certain theories on gold deposition1 which1 even then1 were held by many practical men1 and some scientists1 to be open to question4 ,of late years1 however1 the theory of gold occurrence by deposition from mineral salts has been accepted by all but the mining experts who infest and afflict the gold mining camps of the world4 ,these opine that gold ought to occur in pockets only 7meaning thereby their own74 ,recently ,professor ,joseph ,le ,conte1 at a meeting of the ,american ,institute of ,mining ,engineers1 criticised a notable essay on the ,genesis of ,ore ,deposits1 by ,bergrath ,f4 ,posepny4 ,the ,professor's general conclusions are3 #a4 ,ore deposits1 using the term in its widest sense1 may take place from any kinds of waters1 but especially from alkaline solutions1 for these are the natural solvents of metallic sulphides1 and metallic sulphides are usually the original form of such deposits4 #b4 ,they may take place from waters at any temperature and any pressure1 but mainly from those at high temperature and under heavy pressure1 because1 on account of their great solvent power1 such waters are heavily freighted with metals4 #c4 ,the depositing waters may be moving in any direction1 up-coming1 horizontally moving1 or even sometimes down-going1 but mainly up-coming2 because by losing heat and pressure at every step such waters are sure to deposit abundantly4 #d4 ,deposits may take place in any kind of waterways--in open fissures1 in incipient fissures1 joints1 cracks1 and even in porous sandstone1 but especially in great open fissures1 because these are the main highways of ascending waters from the greatest depths4 #e4 ,deposits may be found in many regions and in many kinds of rocks1 but mainly in mountain regions1 and in metamorphic and igneous rocks1 because the thermosphere is nearer the surface1 and ready access thereto through great fissures is found mostly in these regions and in these rocks4 ,these views are in accordance with nearly all modern research into this interesting and fruitful subject4 ,among the theories which they discredit is that ore bodies may usually be assumed to become richer in depth4 ,as applied to gold lodes the teaching of experience does not bear out this view4 ,if it be taken into account that the time in which most of our auriferous siliceous lodes were formed was probably that indicated in ,genesis as before the first day or period when the earth was without form and void1 and darkness was upon the face of the deep1 it will be realised that the action we behold now taking place in a small way in volcanic regions1 was probably then almost universal4 ,the crust of the earth had cooled sufficiently to permit water to lie on its surface1 probably in hot shallow seas1 like the late ,lake ,rotomahana4 ,plutonic action would be very general1 and volcanic mud1 ash1 and sand would be ejected and spread far and wide1 which1 sinking to the bottom of the water1 may possibly be the origin of what we now designate the azoic or metamorphic slates and schists1 as also the early ,cambrian and ,silurian strata4 ,these1 from the superincumbent weight and internal heat1 became compacted1 and1 in some cases1 crystallised1 while at the same time1 from the ingress of the surface waters to the heated regions below1 probably millions of geysers were spouting their mineral impregnated waters in all directions2 and in places where the crust was thin1 explosions of super-heated steam caused huge upheavals1 rifts1 and chasms1 into which these waters returned1 to be again ejected1 or to be the cause of further explosions4 ,later1 as the cooling-process continued1 there would be shrinkages of the earth's crust causing other fissures2 intrusive granites further dislocated and upheaved the slates4 ,about this age1 probably1 when really dry land began to appear1 came the first formation of mineral lodes1 and the waters1 heavily charged with silicates1 carbonates of lime1 sulphides1 etc41 in solution1 commenced to deposit their contents in solid form when the heat and pressure were removed4 ,i am aware that part of the theory here propounded as to the probable mode of formation of the immense sedimentary beds of the ,archaic or ,azoic period is not altogether orthodox--i4e41 that the origin of these beds is largely due to the ejection of mud1 sand1 and ashes from subterraneous sources1 which1 settling in shallow seas1 were afterwards altered to their present form4 ,it is difficult1 however1 to believe that at this very early period of geologic history so vast a time had elapsed as would be required to account for these enormous depositions of sediment1 if they were the result only of the degradation of previously elevated portions of the earth's surface by water agency4 ,glacial action at that time would be out of the question4 ,but what about the metals8 ,whence came the metallic gold of our reefs and drifts8 ,what was it originally--a metal or a metallic salt1 and if the latter1 what was its nature8--chloride1 sulphide1 or silicate1 one1 or all three8 ,i incline to the latter hypothesis4 ,all three are known1 and the chemical conditions of the period were favorable for their natural production4 ,assuming that they did exist1 the task of accounting for the mode of occurrence of our auriferous quartz lodes is comparatively simple4 ,chloride of gold is at present day contained in sea water and in some mineral waters1 and would have been likely to be more abundant during the ,azoic and early ,paleozoic period4 ,sulphide of gold would have been produced by the action of sulphuretted hydrogen2 hence probably our auriferous pyrites lodes1 while silicate of gold might have resulted from a combination of gold chlorides with silicic acid1 and thus the frequent presence of gold in quartz is accounted for4 ,a highly interesting and instructive experiment1 showing how gold might be1 and probably was1 deposited in quartz veins1 was carried out by ,professor ,bischof some years ago4 ,he1 having prepared a solution of chloride of gold1 added thereto a solution of silicate of potash1 whereupon1 as he states1 the yellow colour of the chloride disappeared1 and in half an hour the fluid turned blue1 and a gelatinous dark-blue precipitate appeared and adhered to the sides of the vessel4 ,in a few days moss-like forms were seen on the surface of the precipitate1 presumably approximating to what we know as dendroidal gold--that is1 having the appearance of moss1 fern1 or twigs4 ,after allowing the precipitate to remain undisturbed under water for a month or two a decomposition took place1 and in the silicate of gold specks of metallic gold appeared4 ,from this1 the ,professor argues1 and with good show of reason1 that as we know now that the origin of our quartz lodes was the silicates contained in certain rocks1 it is probable that a natural silicate of gold may be combined with these silicates4 ,if this can be demonstrated1 the reason for the almost universal occurrence of gold in quartz is made clear4 ,about #ahgj1 ,mr4 ,skey1 analyst to the ,new ,zealand ,geological ,survey ,department1 made a number of experiments of importance in respect to the occurrence of gold4 ,these experiments were summarised by ,sir ,james ,hector in an address to the ,wellington ,philosophical ,society in #ahgb4 ,mr4 ,skey's experiments disproved the view generally held that gold is unaffected by sulphur or sulphuretted hydrogen gas1 and showed that these elements combined with avidity1 and that the gold thus treated resisted amalgamation with mercury4 ,mr4 ,skey proved the act of absorption of sulphur by gold to be a chemical act1 and that electricity was generated in sufficient quantity and intensity during the process to decompose metallic solutions4 ,sulphur in certain forms had long been known to exercise a prejudicial effect upon the amalgamation of gold1 but this had always been attributed to the combination of the sulphur with the quicksilver used4 ,now1 however1 it is certain that the sulphurising of the gold must be taken into account4 ,we must remember that the particles of gold in the stone may be enveloped with a film of auriferous sulphide1 by which they are protected from the solvent actions of the mercury4 ,the sulphurisation of the gold gives no ocular manifestation by change of colour or perceptible increase of weight1 as in the case of the formation of sulphides of silver1 lead and other metals1 on account of the extremely superficial action of the sulphur1 and hence probably the existence of the gold sulphide escaped detection by chemists4 ,closely allied to this subject is the investigation of the mode in which certain metals are reduced from their solutions by metallic sulphides1 or1 in common language1 the influence which the presence of such substances as mundic and galena may exercise in effecting the deposit of pure metals1 such as gold1 in mineral lodes4 ,the close relation which the richness of gold veins bears to the prevalence of pyrites has been long familiar both to scientific observers and to practical miners4 ,the gold is an after deposit to the pyrites1 and1 as ,mr4 ,skey was the first to explain1 due to its direct reducing influences4 ,by a series of experiments ,mr4 ,skey proved that the reduction of the metal was due to the direct action of the sulphide1 and showed that each grain of iron pyrites1 when thoroughly oxidised1 will reduce #ab #a_/d grains of gold from its solution as chloride4 ,he also included salts of platina and silver in this general law1 and demonstrated that solutions of any of these metals traversing a vein rock containing certain sulphides would be decomposed1 and the pure metal deposited4 ,we are thus enabled to comprehend the constant association of gold1 or native alloys of gold and silver1 in veins which traverse rocks containing an abundance of pyrites1 whether they have been formed as the result of either sub-aqueous volcanic outburst or by the metamorphism of the deeper-seated strata which compose the superficial crust of the earth4 ,mr4 ,skey also showed by very carefully conducted experiments that the metallic sulphides are not only better conductors of electricity than has hitherto been supposed1 but that when paired they were capable of exhibiting strong electro-motive power4 ,thus1 if galena and zinc blende in acid solutions be connected in the usual manner by a voltaic pair1 sulphuretted hydrogen is evolved from the surface of the former1 and a current generated which is sufficient to reduce gold1 silver or copper from their solutions in coherent electro-plate films4 ,the attributing of this property of generating voltaic currents1 hitherto supposed to be almost peculiar to metals1 to such sulphides as are commonly found in metalliferous veins1 further led ,mr4 ,skey to speculate how far the currents discovered to exist in such veins by ,mr4 ,e4 ,f4 ,fox might be produced by the gradual oxidation of mixed sulphides1 and that veins containing bands of different metallic sulphides1 bounded by continuing walls1 and saturated with mineral waters1 may constitute under some circumstances a large voltaic battery competent to produce electro-deposition of metals1 and that the order of the deposit of these mineral lodes will be found to bear a definite relation to the order in which the sulphides rank in the table of their electro-motive power4 ,these researches may lead to some clearer comprehension of the law which regulates the distribution of auriferous veins1 and may explain why in some cases the metal should be nearly pure1 while in others it is so largely alloyed with silver4 ,the following extract was lately clipped from a mining paper4 ,if true1 the experiment is interesting3-- ,an ,american scientist has just concluded a very interesting and suggestive experiment4 ,he took a crushed sample of rich ore from ,cripple ,creek1 which carried #aajj ozs4 of gold per ton1 and digested it in a very weak solution of sodium chloride and sulphate of iron1 making the solution correspond as near as practicable to the waters found in ,nature4 ,the ore was kept in a place having a temperature little less than boiling water for six weeks1 when all the gold1 except one ounce per ton1 was found to have gone into solution4 ,a few small crystals of pyrite were then placed in the bottle of solution1 and the gold began immediately to precipitate on them4 ,it was noticeable1 however1 that the pyrite crystals which were free from zinc1 galena1 or other extraneous matter received no gold precipitate4 ,those which had such foreign associations were beautifully covered with fine gold crystals4 ,experimenting in a somewhat similar direction abut twelve months since1 ,i found that the ,west ,australian mine water1 with the addition of an acid1 was a solvent of gold4 ,the idea of boiling it did not occur to me1 as the action was rapid in cold water4 ,assuming1 then1 that gold originally existed as a mineral salt1 when and how did it take metallic form8 ,doubtless1 just in the same manner as we now 7by means of well-known reagents which are common in nature7 precipitate it in the laboratory4 ,with regard to that found in quartz lodes finely disseminated through the gangue1 the change was brought about by the same agency which caused the silicic acid to solidify and take the form in which we now see it in the quartz veins4 ,silica is soluble in solutions of alkaline carbonates1 as shown in ,new ,zealand geysers2 the solvent action being increased by heat and pressure1 so also would be the silicate or sulphide of gold4 ,when1 however1 the waters with their contents were released from internal pressure and began to lose their heat the gold would be precipitated together with the salts of some other metals1 and would1 where the waters could percolate1 begin to accretionise1 thus forming the heavy or specimen gold of some reefs4 ,on this class of deposition ,i shall have more to say when treating of the origin of alluvial gold in the form of nuggets4 ,mr4 ,g4 ,f4 ,becker1 of the ,united ,states ,geological ,survey1 writing of the geology of the ,comstock lode1 says3--,baron ,von ,richthofen was of opinion that fluorine and chlorine had played a large part of the ore deposition in the ,comstock1 and this the writer is not disposed to deny2 but1 on the other hand1 it is plain that most of the phenomena are sufficiently accounted for on the supposition that the agents have been merely solutions of carbonic and hydro-sulphuric acids4 ,these reagents will attack the bisilicates and felspars4 ,the result would be carbonates and sulphides of metals1 earth1 alkalies1 and free quartz1 but quartz and sulphides of the metals are soluble in solutions of carbonates and sulphides of the earths and alkalies1 and the essential constituents of the ore might1 therefore1 readily be conveyed to openings in the vein where they would have been deposited on relief of pressure and diminution of temperature4 ,an advance boring on the #cjjj ft4 level of the ,yellow ,jacket struck a powerful stream of water at #cjfe ft4 7in the west country71 which was heavily charged with hydrogen sulphide1 and had a temperature of #agj degrees ,f41 and there is equal evidence of the presence of carbonic acid in the water of the lower levels4 ,a spring on the #bgjj ft4 level of the ,yellow ,jacket which showed a temperature of about #aej degrees ,f41 was found to be depositing a sinter largely composed of carbonates4 ,it may be worth while here to speak of the probable reason why gold1 and indeed almost all the metals generally occur in shutes in the lodes2 and why1 as is often the case1 these shutes are found to be more or less in a line with each other in parallel lodes1 and why also the junction of two lodes is frequently specially productive4 ,the theory with respect to these phenomena which appears most feasible is1 that at these points certain chemical action has taken place1 by which the deposition of the metals has been specially induced4 ,generally a careful examination of the enclosing rocks where the shute is found will reveal some points of difference from the enclosing rocks at other parts of the course of the lode1 and when ore shutes are found parallel in reefs running on the same course1 bands or belts of similar country rock will be found at the productive points4 ,from this we may fairly reason that at these points the slow stream filling the lode cavity met with a reagent percolating from this particular band of rock1 which caused the deposition of its metals2 and1 indeed1 ,i am strongly disposed to believe that the deposition of metals1 particularly in some loose lodes1 may even now be proceeding4 ,but as in ,nature's laboratory the processes1 if certain1 are slow1 this theory may be difficult to prove4 ,why the junction of lodes is often found to be more richly metalliferous than neighbouring parts is probably because there the depositing reagents met4 ,this theory is well put by ,mr4 ,s4 ,herbert ,cox1 late of ,sydney1 in his useful book1 ,mines and ,minerals4 ,he says3--,it is a well-known fact in all mining districts that the junctions of lodes are generally the richest points1 always supposing that this junction takes place in 'kindly country1' and the explanation of this we think is simple on the aqueous theory of filling of lodes4 ,the water which is traversing two different channels of necessity passes through different belts of country1 and will thus have different minerals in solution4 ,as a case in point1 let us suppose that the water in one lode contained in solution carbonates of lime1 and the alkalies and silica derived form a decomposition of felspars2 and that the other1 charged with hydro-sulphuric acid1 brought with it sulphide of gold dissolved in sulphide of lime4 ,the result of these two waters meeting would be that carbonate of lime would be formed1 hydro-sulphuric acid would be set free1 and sulphide of gold would be deposited1 as well as silica1 which was formerly held in solution by the carbonic acid4 ,most practical men who have given the subject attention will1 ,i think1 be disposed to coincide with this view1 though there are some who hold that the occurrence of these parallel ore shutes and rich deposits at the junctions of lodes is due to extraneous electrical agency4 ,of this1 however ,i have failed to find any satisfactory evidence4 ,there is1 however1 proof that lodes are actually re-forming and the action observed is very interesting as showing how the stratification in some lodes has come about4 ,instances are not wanting of the growth of silica on the sides of the drives in mines4 ,this was so in some of the mines on the ,thames1 ,new ,zealand1 previously mentioned1 where in some cases the deposition was so rapid as to be noticeable from day to day1 whilst the big pump was actually choked by siliceous deposits4 ,in old auriferous workings which have been under water for years1 in many parts of the world1 formations of iron and silica have been found on the walls and roof1 while in mining tunnels which have been long unused stalactites composed of silica and calcite have formed4 ,then1 again1 experiments made by the late ,professor ,cosmo ,newbery1 in ,victoria1 showed that a distinctly appreciable amount of gold1 iron1 and silica 7the latter in granular form7 could be extracted from solid mine timber2 which had been submerged for a considerable time4 ,this reaction then must be in progress at the present time1 and doubtless under certain conditions pyrites would eventually take the place of the timber1 as is the case with some of the long buried driftwood found in ,victorian deep leads4 ,again1 we know that the water from some copper mines is so charged with copper sulphate that if scrap iron be thrown into it1 the iron will be taken up by the sulphuric acid1 and metallic copper deposited in its place4 ,all this tends to prove that the deposition of metals from their salts1 though probably not now as rapid as formerly1 is still ceaselessly going on in some place or another where the necessary conditions are favourable4 ,with regard to auriferous pyritic lodes1 it does not appear even now to be clear1 as some scientists assert1 that their gold is never found in chemical combination with the sulphides of the base metals4 ,on the contrary1 ,i think much of the evidence points in the other direction4 ,i have long been of opinion that it is really so held in many of the ferro-sulphides and arsenio-ferro sulphides4 ,on this subject ,mr4 ,t4 ,atherton contributed a short article in #ahia to the ,australian ,mining ,standard which is worthy of notice4 ,he says1 referring to an occurrence of a ,natural ,sulphide of ,gold3 ,the existence of gold1 in the form of a natural sulphide in conjunction with pyrites1 has often been advanced theoretically1 as a possible occurrence2 but up to the present time has1 ,i believe1 never been established as an actual fact4 ,during my investigation on the ore of the ,deep ,creek mines1 ,nambucca1 ,new ,south ,wales1 ,i have found in them what ,i believe to be gold existing as a natural sulphide4 ,the lode is a large irregular one of pure arsenical pyrites carrying1 in addition to gold and silver1 nickel and cobalt4 ,it exists in a felsite dyke immediately on the coast4 ,surrounding it on all sides are micaceous schists1 and in the neighbourhood about half a mile distant is a large granite hill about #hjj feet high4 ,in the lode and its walls are large quantities of pyro-phyllite1 and in some parts of the mine there are deposits of pure white translucent mica1 but in the ore itself it is a yellow or pale olive green1 and is never absent from the pyrites4 ,from the first ,i was much struck with the exceedingly fine state of division in which the gold existed in the ore4 ,after roasting and very carefully grinding down in an agate mortar1 ,i have never been able to get any pieces of gold exceeding one-thousandth of an inch in diameter1 and the greater quantity is very much finer than this4 ,careful dissolving of the pyrites and gangue so as to leave the gold intact failed to find it in any larger diameter4 ,as this was a very unusual experience in investigations on many other kinds of pyrites1 ,i was led further into the matter4 ,ultimately1 after a number of experiments1 there was nothing left but to test for gold existing as a natural sulphide4 ,taking #bjj gr4 of ore from a sample assaying #ag oz4 fine gold per ton1 grinding it finely and heating for some hours with yellow sodium sulphide--on decomposing the filtrate and treating for gold ,i got a result at the rate of #ab oz4 per ton4 ,this was repeated several times with the same result4 ,this sample came from the lode at the #adj ft4 level1 whilst samples from the higher levels where the ore is more oxidised1 although carrying the gold in exactly the same degree of fineness1 do not give as high a percentage of auric sulphide4 ,it would appear that all the gold in the pyrites 7and ,i have never found any gold existing apart from the pyrites7 has originally taken its place there as a sulphide4 ,professor ,newbery1 who made many valuable suggestions on the subject1 says1 speaking of gold in pyritous lodes3 ,as it 7the gold salt7 may have been in the same solution that deposited the pyrites1 which probably contained its iron in the form of proto-carbonate with sulphates1 it was not easy at first to imagine any ordinary salt of gold2 but this ,i find can be accomplished with very dilute solutions in the presence of an alkaline carbonate and a large excess of carbonic acid1 both of which are common constituents of mineral waters1 especially in ,victoria4 ,this is true of chloride of gold1 and if the sulphide is required in solution1 it is only necessary to charge the solution with an excess of sulphuretted hydrogen4 ,in this matter both sulphides may be retained in the same solution1 depositing gradually with the escape of the carbonic acid4 ,pyritic lodes usually contain a considerable proportion of calcareous matter1 mostly carbonates1 and consequently it appears not improbable that the gold may remain in some instances as a sulphide1 particularly in samples of pyrites1 in which it cannot be detected even by the microscope until by calcination the iron sulphide is changed to an oxide1 wherein the gold may be seen in minute metallic specks4 ,the whole subject is full of interest1 and careful scientific investigation may lead to astonishing results4 ,,chapter ,v ,,the ,,genesiology ,,of ,,gold--,,auriferous ,,drifts ,having considered the origin of auriferous lodes1 and the mode by which in all probability the gold was conveyed to them and deposited as a metal1 it is necessary also to inquire into the derivation of the gold of our auriferous drifts1 and the reasons for its occurrence therein4 ,when quite a lad on the ,victorian alluvial fields1 ,i frequently heard old diggers assert that gold grew in the drifts where found4 ,at the time we understood this to mean that it grew like potatoes2 and1 although not prepared with a scientific argument to prove that such was not so1 the idea was generally laughed at4 ,i have lived to learn that these old hard-heads were nearer the truth than possibly they clearly realised1 and that gold does actually grow or agglomerate2 and1 indeed1 is probably even now thus growing1 though it is likely that the chemical and electric action in the mineral waters flowing through the drifts is not in this age nearly so active as formerly4 ,most boys have tried the experiment of dipping a clean-bladed knife into sulphate of copper1 and so depositing on the steel a film of copper1 which adheres closely until worn away4 ,this is a simple demonstration of a hydro-metallurgical process1 though probably young hopeful is not aware of the fact2 and it is really by an enlargement of this process that our beautiful and artistic gold-and silver-plated ware is produced4 ,in the great laboratory of ,nature similar chemical depositions have taken place in the past1 and may still be in progress2 indeed1 there is sound scientific reason to suppose that in certain localities this is even now the case1 and that in this way much of our so-called alluvial gold has been formed1 that is1 by the deposition on metallic bases of the gold held in solution4 ,we will1 however1 take1 to begin with1 the generally accepted theory as to the occurrence of alluvial gold4 ,first1 let it be said1 that certain alluvial gold is unquestionably derived from the denudation of quartz lodes4 ,such is the gold dust found in many ,asiatic and ,african rivers1 in the great placer mines of ,california1 as also the gold dust gained from the beach sand on the west coast of ,new ,zealand1 or in the enormous alluvial drifts of the ,shoalhaven ,valley1 ,new ,south ,wales4 ,of the first1 many fabulous tales are told to account for its being found in particular spots each summer after the winter floods1 and miraculous agency was asserted1 while the early beachcombers of the ,hokitika district found an equally ridiculous derivation for their gold1 which was always more plentiful after heavy weather4 ,they imagined that the breakers were disintegrating some abnormally rich auriferous reefs out at sea1 and that the resultant gold was washed up on the beach4 ,the facts are simply1 with regard to the rivers1 that the winter floods break down the drifts in the banks and agitate the auriferous detritus1 thus acting as natural sluices1 and cause the metal to accumulate in favourable spots2 whilst on the ,new ,zealand coast the heavy seas breaking on the shingly beach1 carry off the lighter particles1 leaving behind the gold1 which is so much heavier4 ,these beaches are composed1 as also are the terraces behind1 of enormous glacial and fluvial deposits1 all containing more or less gold1 and extend inland to the foot of the mountains4 ,it is almost certain that the usually fine gold got by hydraulicing in ,californian canyons1 in the gullies of the ,new ,zealand ,alps1 and the great ,new ,south ,wales drifts1 is largely the result of the attrition of the boulders and gravel of moraines1 which has thus freed1 to a certain extent1 the auriferous particles4 ,but when we find large nuggety masses of high carat gold in the beds of dead rivers1 another origin has to be sought4 ,as previously stated1 there is fair reason to assume that at least three salts of gold have existed1 and1 possibly1 may still be found in ,nature--silicate1 sulphide1 and chloride4 ,all of these are soluble and in the presence of certain reagents1 also existing naturally1 can be deposited in metallic form4 ,therefore1 if1 as is contended1 reef gold was formed with the reefs from solutions in mineral waters1 by inferential reasoning it can be shown that much of our alluvial gold was similarly derived4 ,the commonly accepted theory1 however1 is that the alluvial matter of our drifts has been ground out of the solid siliceous lodes by glacial and fluvial action1 and that the auriferous leads have been formed by the natural sluicing operations of former streams4 ,to this1 however1 there are several insuperable objections4 ,first1 how comes it that alluvial gold is usually superior in purity to the reef gold immediately adjacent8 ,second1 why is it that masses of gold1 such as the huge nuggets found in ,victoria and ,new ,south ,wales1 have never been discovered in lodes8 ,third1 how is it that these heavy masses which1 from their specific gravity1 should be found only at the very bottom of the drifts1 if placed by water action1 are sometimes found in all positions from the surface to the bottom of the wash8 ,and1 lastly1 why is it that when an alluvial lead is traced up to1 or down from1 an auriferous reef1 that the light1 angular gold lies close to the roof1 while the heavy masses are often placed much farther away8 ,any one who has worked a ground sluice knows how extremely difficult it is with a strong head of water to shift from its position an ounce of solid gold4 ,what1 then1 would be the force required to remove the ,welcome ,nugget8 ,under certain circumstances1 ,niagara would not be equal to the task4 ,the generally smooth appearance of alleged alluvial gold is adduced as an argument in favour of its having been carried by water from its original place of deposit1 and thus in transit become waterworn2 while some go so far as to say that it was shot out of the reefs in a molten state4 ,the latter idea has been already disposed of1 but if not1 it may be dismissed with the statement that the heat which would melt silica in the masses met with in lodes would sublimate any gold contained1 and dissipate it1 not in nuggets but in fumes4 ,with regard to the assumed waterworn appearance of alluvial gold1 ,i have examined with the microscope the smooth surface of more than one apparently waterworn nugget1 and found that it was not scratched and abraded1 as would have been the case had it been really waterworn1 but that it presented the same appearance1 though infinitely finer in grain1 as the surface of a piece of metal fresh from the electrical plating-bath4 ,mr4 ,daintree1 of the ,victorian ,geological ,survey1 many years ago discovered accidentally that gold chloride would deposit its metal on a metallic base in the presence of any organic substance4 ,mr4 ,daintree found that a piece of undissolved gold in a bottle containing chloride of gold in solution had1 owing to a portion of the cork having fallen into the liquid1 grown or accretionised so much that it could not be extracted through the neck4 ,this lead ,mr4 ,charles ,wilkinson1 who has contributed much to our scientific knowledge of metallurgy1 to experiment further in the same direction4 ,he says3 ,using the most convenient salt of gold1 the terchloride1 and employing wood as the decomposing agent1 in order to imitate as closely as possible the organic matter supposed to decompose the solution circulating through the drifts1 ,i first immersed a piece of cubic iron pyrites taken from the coal formation of ,cape ,otway1 far distant from any of our gold rocks1 and therefore less likely to contain gold than other pyrites4 ,the specimen 7,no4 #a7 was kept in dilute solution for about three weeks1 and is completely covered with a bright film of gold4 ,i afterwards filed off the gold from one side of a cube crystal to show the pyrites itself and the thickness of the surrounding coating1 which is thicker than ordinary notepaper4 ,if the conditions had continued favourable for a very lengthened period1 this specimen would doubtless have formed the nucleus of a large nugget4 ,iron1 copper1 and arsenical pyrites1 antimony1 galena1 molybdenite1 zinc blende1 and wolfram were treated in the above manner with similar results4 ,in the above experiments a small chip of wood was employed as the decomposing agent4 ,in one instance ,i used a piece of leather4 ,all through the wood and leather gold was disseminated in fine particles1 and when cut through the characteristic metallic lustre was brightly reflected4 ,the first six of these sulphides were also operated upon simply in the solution without organic matter2 but they remained unaltered4 ,wilkinson found that when the solution of gold chloride was as strong as1 say1 four grains to the ounce of water1 that the pyrites or other base began to decompose1 and the iron sulphide changed to yellow oxide1 the gossan of our lodes1 and that though the gold was deposited1 this occurred in an irregular way1 and it was coated with a dark brown powdery film something like the black gold1 often found in drifts containing much ferruginous matter4 ,such were the curious ,victorian nuggets ,spondulix and ,lothair4 ,professor ,newbery also made a number of similar experiments1 and arrived at like results4 ,he states as follows3 ,i placed a cube of galena in a solution of chloride of gold1 with free access of air1 and put in organic matter2 gold was deposited as usual1 in a bright metallic film1 apparently completely coating the cube4 ,after a few months the film burst along the edges of the cube1 and remained in that state with the cracks open without any further alteration in size or form being apparent4 ,upon removing it a few days ago and breaking it open1 ,i found that a large portion of the galena had been decomposed1 forming chloride and sulphate of lead and free sulphur1 which were mixed together1 encasing a small nucleus of undecomposed sulphate of lead4 ,the formation of these salts had exerted sufficient force to burst open the gold coating1 which upon the outside had the mammillary form noticed by ,wilkinson1 while the inside was rough and irregular with crystals forcing their way into the lead salts4 ,had this action continued undisturbed1 the result would have been a nugget with a nucleus of lead salts1 or if there had been a current to remove the results of decomposition1 a nugget without a nucleus of foreign matter4 ,but ,newbery also made another discovery which still further establishes the probability of the accretionary growth of gold in drifts4 ,in the first experiments both investigators used organic substances as the reagent to cause the deposit of gold on its base1 and in each case these substances whether woodchips1 leather1 or even dead flies1 were found to be so absolutely impregnated with gold as to leave a golden skeleton when afterwards burned4 ,timber found in the ,ballarat deep leads has been proved to be similarly impregnated4 ,newbery found that gold could also be deposited on sulphurets without any other reagent4 ,he says3 ,in our mineral sulphurets1 however1 we have agents which are not only capable of reducing gold and silver from solution1 but besides are capable of locating them when so reduced in coherent and bulky masses4 ,thus the aggregation of the nuggety forms of gold from solution becomes a still more simple matter1 only one reagent being necessary1 so that there is a greater probability of such depositions obtaining than were a double process necessary4 ,knowing the action of sulphides1 the manner or the mode of formation of a portion at least of these nuggets seems apparent4 ,conceive a stream or river fed by springs rising in a country intersected by auriferous reefs1 and consequently in this case carrying gold in solution2 the drift of such a country must be to a greater or lesser extent pyritous1 so that the debris forming the beds of these streams or rivers will certainly contain nodules of such matters disseminated or even stopping them in actual contact with the flow of water4 ,it follows1 then1 from what has been previously affirmed1 that there will be a reduction of gold by these nodules1 and that the metal thus reduced will be firmly attached to them1 at first in minute spangles isolated from each other1 but afterwards accumulating and connecting in a gradual manner at that point of the pyritous mass most subject to the current until a continuous film of some size appears4 ,this being formed the pyrites and gold are to a certain extent polarised1 the film or irregular but connected mass of gold forming the negative1 and the pyrites the positive end of a voltaic pair2 and so according as the polarisation is advanced to completion the further deposition of gold is changed in its manner from an indiscriminate to an orderly and selective deposition concentrated upon the negative or gold plate4 ,the deposition of gold being thus controlled1 its loss by dispersion or from the crumbling away of the sustaining pyrites is nearly or quite prevented1 a conservative effect which we could scarcely expect to obtain if organic matter were the reducing agent4 ,meanwhile there is a gradual wasting away of the pyrites or positive pole1 its sulphur being oxidised to sulphuric acid and its iron to sesquioxide of iron1 or hematite1 a substance very generally associated with gold nuggets4 ,according to the original size of the pyritous mass1 the protection it receives from the action of oxidising substances other than gold1 the strength of the gold solution1 length of exposure to it1 the rate of supply and velocity of stream1 will be the size of the gold nugget4 ,as to the size of a pyritous mass necessary to produce in this manner a large nugget1 it is by no means considerable4 ,a mass of common pyrites 7bisulphide of iron7 weighing only #ab lbs4 is competent for the construction of the famous ',welcome ,nugget1' an ,australian find having weight equal to #aeb lbs4 avoirdupois4 ,such masses of pyrites are by no means uncommon in our drifts or the beds of our mountain streams4 ,thus we find that no straining of the imagination is required to conceive of this mode of formation for the huge masses of gold found in ,australia in particular1 such as the ,welcome ,nugget1 #ahd lbs4 #i oz42 the ,welcome ,stranger1 a surface nugget1 #aij lbs4 after smelting2 the ,braidwood specimen nugget1 #cej lbs41 two-thirds gold2 besides many other large masses of almost virgin gold which have been obtained from time to time in the alluvial diggings4 ,the author has made a number of experiments in the same direction1 but more with the idea of demonstrating how possibly gold may in certain cases have been deposited in siliceous formations after such formations had solidified4 ,some of the results were remarkable and indeed unexpected4 ,i found that ,i could produce artificial specimens of auriferous quartz from stone which had previously contained no gold whatever1 also that it was not absolutely necessary that the stone so treated should contain any metallic sulphides4 ,the following was contributed by the author and is from the ,transactions of the ,australasian ,institute of ,mining ,engineers for #ahic3-- ,,the ,,deposition ,,of ,,gold4 ,the question as to how gold was originally deposited in our auriferous lodes is one to which a large amount of attention has been given1 both by mineralogists and practical miners1 and which has been hotly argued by those who held the igneous theory and those who pronounced for the aqueous theory4 ,it was held by the former that as gold was not probably existent in nature in any but its metallic form1 therefore it had been deposited in its siliceous matrix while in a molten state1 and many ingenious arguments were adduced in support of this contention4 ,of late1 however1 most scientific men1 and indeed many purely empirical inquirers 7using the word empirical in its strict sense7 have come to the conclusion that though the mode in which they were composed was not always identical1 all lodes1 including auriferous formations1 were primarily derived from mineral-impregnated waters which deposited their contents in fissures caused either by the cooling of the earth's crust or by volcanic agency4 ,the subject is one which has long had a special attraction for the writer1 who has published several articles thereon1 wherein it was contended that not only was gold deposited in the lodes from aqueous solution1 but that some gold found in form of nuggets had not been derived from lodes but was nascent in its alluvial bed2 and for this proof was afforded by the fact that certain nuggets have been unearthed having the shape of an adjacent pebble or angular fragment of stone indented in them4 ,moreover1 no true nugget of any great size has ever been found in a lode such as the ,welcome1 #baei oz41 or the ,welcome ,stranger1 #bbhj oz42 while it was accidentally discovered some years ago that gold could be induced to deposit itself from its mineral salt to the metallic state on any suitable base1 such as iron sulphide4 ,following out this fact1 ,i have experimented with various salts of gold1 and have obtained some very remarkable results4 ,i have found it practicable to produce most natural looking specimens of auriferous quartz from stone which previously1 as proved by assay1 contained no gold whatever4 ,moreover1 the gold1 which penetrates the stone in a thorough manner1 assumes some of the more natural forms4 ,it is always more or less mammillary1 but at times1 owing to causes which ,i have not yet quite satisfied myself upon1 is decidedly dendroidal1 as may be seen in one of the specimens which ,i have submitted to members4 ,moreover1 ,i find it possible to moderate the colour and to produce a specimen in which the gold shall be as ruddy yellow as in the ferro-oxide gangue of ,mount ,morgan1 or to tone it to the pale primrose hue of the product of the ,croydon mines4 ,i note that the action of the bath in which the stone is treated has a particularly disintegrating effect on many of the specimens4 ,some1 which before immersion were of a particularly flinty texture1 became in a few weeks so friable that they could be broken up by the fingers4 ,so far as my experiments have extended they have proved this1 that it was not essential that the silica and gold should have been deposited at the one time in auriferous lodes4 ,a non-auriferous siliceous solution may have filled a fissure1 and1 after solidifying1 some volcanic disturbance may have forced water impregnated with a gold salt through the interstices of the lode formation1 when1 if the conditions were favourable1 the gold would be deposited in metallic forms4 ,i prefer1 for reasons which will probably be understood1 not to say exactly by what process my results are obtained1 but submit specimens for examination4 7#a7 ,piece of previously non-gold bearing stone4 ,locality near ,adelaide1 now showing gold freely in mammillary and dendroidal form4 7#b7 ,stone from ,new ,south ,wales1 showing gold artificially introduced in interstices and on face4 7#c7 ,stone from ,west ,australia1 very glassy looking1 now thoroughly impregnated with gold2 the mammillary formation being particularly noticeable4 7#d7 ,somewhat laminated quartz from ,victoria1 containing a little antimony sulphide4 ,in this specimen the gold not only shows on the surface but penetrates each of the laminations1 as is proved by breaking4 7#e7 ,consists of fragments of crystallised carbonate of lime from ,tarrawingee1 in which the gold is deposited in spots1 in appearance like ferrous oxide1 until submitted to the magnifying glass4 ,the whole subject is worthy of much more time than ,i can possibly give it4 ,the importance lies in this3 ,that having found how the much desired metal may have been deposited in its matrix1 the knowledge should help to suggest how it may be economically extracted therefrom4 ,a very remarkable nugget weighing #af #c_/d oz4 was sluiced from near the surface in one of my own mining properties at ,woodside1 ,south ,australia1 some years ago1 which illustrated the nuclear theory very beautifully4 ,this nugget is very irregular in shape1 fretted and chased as though with a jeweller's graving tool1 showing plainly the shape of the pyritous crystals on which it was formed while the interstices were filled with red hematite iron just as found in artificially formed nuggets on a sulphide of iron base4 ,the author has a nugget from the same locality weighing about #a #a_/b oz4 which exhibits in a marked degree the same characteristics1 as indeed does most of the alluvial gold found in the ,mount ,lofty ,ranges2 also a nugget from near the centre of ,australia weighing four ounces1 in which the original crystals of pyrites are reproduced in gold just as an iron horse-shoe1 placed in a launder through which cupriferously impregnated water flows1 will in time be changed to nearly pure copper and yet retain its shape4 ,now with regard to the four points ,i have put as to the apparent anomalies of occurrence of alluvial gold4 ,the reason why alluvial gold is of finer quality as a rule than reef is probably because while gold and silver1 which have a considerable affinity for each other1 were presumably dissolved from their salts and held in solution in the same mineral water1 they would in many cases not be deposited together1 for the reason that silver is most readily deposited in the presence of alkalies1 which would be found in excess in mineral waters coming direct from the basic rocks1 while gold is induced to precipitate more quickly in acid solutions1 which would be the character of the waters after they had been exposed to atmospheric action and to contact with organic matters4 ,this1 then1 may explain not only the comparatively greater purity of the alluvial gold1 but also why big nuggets are found so far from auriferous reefs1 and also why heavy masses of gold have been frequently unearthed from among the roots even of living trees1 but more particularly in drifts containing organic matter1 such as ancient timber4 ,all1 then1 that has been adduced goes to establish the belief that the birthplace of our gold is in certain of the earlier rocks comprising the earth's crust1 and that its appearance as the metal we value so highly is the result of electro-chemical action1 such as we can demonstrate in the laboratory4 ,,chapter ,,vi ,,gold ,,extraction ,we now come to a highly important part of our subject1 the practical treatment of ores and matrixes for the extraction of the metals contained4 ,the methods employed are multitudinous1 but may be divided into four classes1 namely1 washing1 amalgamating with mercury1 chlorinating1 cyaniding and other leaching processes1 and smelting4 ,the first is used in alluvial gold and tin workings and in preparing some silver1 copper1 and other ores for smelting1 and consists merely in separating the heavier metals and minerals from their gangues by their greater specific gravity in water4 ,the second includes the trituration of the gangue and the extraction of its gold or silver by means of mercury4 ,chlorinating and leaching generally is a process whereby metals are first changed by chemical action into their mineral salts1 as chloride of gold1 nitrate of silver1 sulphate of copper1 and being dissolved in water are afterwards redeposited in the metallic form by means of well-known re-agents4 ,in really successful mining it is in the last degree important that the mode of extraction of metals in the most scientific manner should be thoroughly understood1 but as a general rule the science of metallurgy is but very superficially grasped even by those whose special business it is to treat ore bodies in order to extract their metalliferous contents1 and whether in quartz crushing mill1 lixiviating1 or smelting works there is much left to be desired in the method of treating our ores4 ,my attention was recently attracted to an article written by ,mr4 ,f4 ,a4 ,h4 ,rauft1 ,m4,e41 from which ,i make the following extract3 ,he says1 speaking of the ,german treatment of ores and the mode of procedure in ,australia1 ,it is high time that ,government stepped in and endeavoured by prompt and decisive action to bring the mining industry upon a sound and legitimate basis4 ,though our ranges abound in all kinds of minerals that might give employment to hundreds of thousands of people1 mining is carried on in a desultory1 haphazard fashion4 ,there is no system1 and the treatment of ores is of necessity handed over to the tender mercies of men who have not even an idea of what an intricate science metallurgy has become in older countries4 ,during many years of practical experience ,i have never known a single instance where a lode1 on being worked1 gave a return according to assay1 and ,i have never known any mine where some of the precious metals could not be found in the tailings or slag4 ,the ,germans employ hundreds of men in working for zinc which produces some two or three per cent to the ton2 here the same percentage of tin could hardly be made payable1 and this1 mark you1 is owing not to cheaper labour alone1 but chiefly to the labour-saving appliances and the results of the researches of such gigantic intellects as ,professor ,kerl and many others1 of whom we in this country never even hear4 ,go into any of the great mining works of central ,germany1 and you may see acres covered by machinery ingeniously constructed to clean1 break1 and sort1 and ultimately deliver the ores into trucks or direct into the furnace1 and the whole under the supervision of a youngster or two4 ,when a parcel of ore arrives at any of the works1 say ,freiberg or ,clausthal1 it is carefully assayed by three or four different persons and then handed over to practical experts1 who are expected to produce the full amount of previous metal according to assay2 and if by any chance they do not1 a fixed percentage of the loss is deducted from their salary2 or1 if the result is in excess of this assay which is more frequently the case1 a small bonus is added to their pay4 ,compare this system with our own wasteful1 reckless method of dealing with our precious metals1 and we may hide our heads in very shame4 ,all really practical men will1 ,i think1 endorse ,mr4 ,rauft's opinion4 ,well organised and conducted schools of mines will gradually ameliorate this unsatisfactory state of things1 and ,i hope before long that we shall have none but qualified certificated men in our mines4 ,in the meantime a few practical hints1 particularly on that very difficult branch of the subject1 the saving of gold1 will1 it is hoped1 be found of service4 ,the extraction of gold from the soil is an industry so old that its first introduction is lost in the mist of ages4 ,as before stated1 gold is one of the most widely disseminated of the metals1 and man1 so soon as he had risen from the lowest forms of savagery1 began to be attracted by the kingly metal1 which he found to be easily fashioned into articles of ornament and use1 and to be practically non-corrodable4 ,what we now term the dish or pan1 then1 doubtless generally a wooden bowl1 was the appliance first used2 but they had also an arrangement1 somewhat like our modern blanket tables1 over which the auriferous sand was passed by means of a stream of water4 ,the sands of some of the rivers from which portions of the gold supply of the old world was derived are still washed over year after year in exactly the same manner as was employed1 probably1 thousands of years ago1 the labour1 very arduous1 being often carried on by women1 who1 standing knee deep in water1 pan off the sand in wooden bowls much as the digger in modern alluvial fields does with his tin dish4 ,the resulting gold often consists of but a grain or two of fine dust-gold1 which is carefully collected in quills1 and so exported or traded for goods4 ,the digger of to-day having discovered payable alluvial dirt at such a depth as to permit of its being profitably worked by small parties of men with limited or no capital1 procures first a half hogshead for a puddling tub1 a cradle1 or long tom1 and tin dish4 ,the wash dirt1 as the auriferous drift is usually termed1 contains a considerable admixture of clay of a more or less tenacious character1 and the bulk of this has to be puddled and so disintegrated before the actual separation of the gold is attempted in the cradle or dish4 ,this is done in the tub by constantly stirring with a shovel1 and changing the water as it becomes charged with the floating argillaceous1 or clayey1 particles4 ,the gravel is then placed in the hopper of the cradle which separates the larger stones and pebbles1 the remainder passing down over inclined ledges as the cradle is slowly rocked and supplied with water4 ,at the bottom of each ledge is a riffle to arrest the particles of gold4 ,sometimes1 when the gold is very fine1 amalgamated copper plates are introduced and the lower ledges are covered with green baize to act as blanket tables and catch gold which might otherwise be lost4 ,a long tom is a trough some #ab feet in length by #bj inches in width at the upper end1 widening to #cj inches at the lower end2 it is about #i inches deep and has a fall of #a inch to a foot4 ,an iron screen is placed at the lower end where large stones are caught1 and below this screen is the riffle box1 #ab feet long1 #c feet wide1 and having the same inclination as the upper trough4 ,it is fitted with several riffles in which mercury is sometimes placed4 ,much more work can be done with this appliance than with the cradle1 which it superseded4 ,of course1 the gold must be coarse and water plentiful4 ,when1 however1 the claim is paying1 and the diggings show signs of some permanency1 a puddling machine is constructed4 ,this is described in the chapter called ,rules of ,thumb4 ,hydraulicing and ground sluicing is a very cheap and effective method of treating large quantities of auriferous drift1 and1 given favourable circumstances1 such as a plentiful supply of water with good fall and extensive loose auriferous deposits1 a very few grains to the ton or load can be made to give payable returns4 ,the water is conveyed in flumes1 or pipes to a point near where it is required1 thence in wrought iron pipes gradually reduced in size and ending in a great nozzle somewhat like that of a fireman's hose4 ,the ,monitor1 as it is sometimes called1 is generally fixed on a movable stand1 so arranged that the strong jet of water can be directed to any point by a simple adjustment4 ,a face is formed in the drift1 and the water played against the lower portion of the ledge1 which is quickly undermined1 and falls only to be washed away in the stream of water1 which is conducted through sluices with riffles1 and sometimes over considerable lengths of amalgamated copper plates4 ,this class of mining has been most extensively carried out in ,california and ,new ,zealand1 and some districts of ,victoria1 but the truly enormous drifts of the ,shoalhaven district in ,new ,south ,wales must in the near future add largely to the world's gold supply4 ,these drifts which are auriferous from grass roots to bed rock extend for nearly fifty miles1 and are in places over #bjj feet deep4 ,want of capital and want of knowledge has hitherto prevented their being profitably worked on a large scale4 ,the extraction of reef gold from its matrix is a much more complicated process1 and the problem how most effectively to obtain that great desideratum--a complete separating and saving operation--is one which taxes the skill and evokes the ingenuity of scientific men all over the world4 ,the difficulty is that as scarcely any two gangues1 or matrixes1 are exactly alike1 the treatment which is found most effective on one mine will often not answer in another4 ,much also depends on the proportion of gold to the ton of rock under treatment1 as the most scientific and perfect processes of lixiviation hitherto adopted will not pay1 even when all other conditions are favourable1 if the amount of gold is much under half an ounce to the ton and even then will leave but a very small profit4 ,if1 however1 the gold is free1 and the lode large1 a very few pennyweights 7or dollars1 as the ,americans say7 to the ton will pay handsomely4 ,the mode of extraction longest in vogue1 and after all the cheapest and most effective1 for free milling ores where the gold is not too fine1 is amalgamation with mercury1 which metal has a strong affinity for gold1 silver1 and copper4 ,as to crushing appliances1 ,i shall not say much4 ,their name is legion for they are many1 and the same may be said of concentrators4 ,it may be old-fashioned1 but ,i admit my predilection is still in favour of the stamper-battery1 for the reason that though it may be slower in proportion to the power employed1 it is simple and not liable to get out of order1 a great advantage when one has so often to depend on men who bring to their work a supply principally of main strength and stupidity4 ,for the same reason ,i prefer the old draw and lift1 and plunger pumps to newer but more complicated water-lifters4 ,on both these points1 however1 ,i am constrained to admit that my opinion has recently been somewhat shaken4 ,i have lately seen two appliances which appear to mark a new era in the scientific progress of mining4 ,one is the ,griffin ,mill1 the other the ,lemichel ,siphon ,elevateur4 ,the first is in some respects on the principle of the ,huntingdon ,mill4 ,the latter1 if the inventor may be believed and the results seem to show he can be1 will be a wonderful factor in developing not only mining properties where a preponderance of water is the trouble1 but also in providing an automatic1 and therefore extremely cheap1 mode of water-raising and supply1 which in simplicity is thus far unexampled4 ,atmospheric pressure alone is relied on4 ,the well-known process of the syphon is the basis1 but with this essential difference1 that a large proportion of the water drawn up to the apex of the syphon is super-elevated to heights regulated by the fall obtained in the outlet leg4 ,this elevation can be repeated almost indefinitely by returning the waste water to the reservoirs4 ,the ,lemichel ,syphon is a wonderful1 yet most simple application of natural force4 ,the inlet leg of the syphon is larger in diameter than the outlet leg1 and is provided at the bottom with a valve or clack4 ,the outlet leg has a tap at its base4 ,at the apex are two chambers1 with an intermediary valve1 regulated by a counterpoise weighted lever4 ,the first chamber has also a vertical valve and pipe4 ,when the tap of the outlet leg is turned1 the water flows as in an ordinary syphon1 but owing to the rapid automatic opening and shutting of the valve in the first chamber about #de per cent of the water is diverted1 and may be raised to a height of many feet above the top of the syphon4 ,it need not be impressed on practical men that if this invention will perform anything like what is claimed for it1 its value can hardly be calculated4 ,after a careful inspection of the appliance in operation1 ,i believe it will do all that is stated4 ,another invention is combined with this which1 by a very small expenditure of fuel1 will enable the first point of atmospheric pressure to be attained4 ,in this way the unwatering of mines may be very inexpensively effected1 or water for irrigation purposes may be raised from an almost level stream4 ,the ,griffin ,mill is a centrifugal motion crusher with one roller only1 which1 by an ingenious application of motive force1 revolves in an opposite direction to its initial momentum1 and which evolves a force of #fjjj lb4 against the tire1 which is only #cj inches in diameter4 ,for hard quartz the size should be increased by at least #f inches4 ,it is claimed for this mill that it will pulverise to a gauge of #ijj holes to the square inch from #a #a_/b to #b #a_/b tons per hour1 or1 say roughly1 #aej tons per week4 ,the ,huntingdon mill is a good crusher and amalgamator where the material to be operated on is comparatively soft1 but does not do such good work when the stone is of a hard flinty nature4 ,a ,no4 #d ,dodge stone-breaker working about #h hours will keep a five-foot ,huntingdon mill going #bd hours1 and an automatic feeder is essential4 ,for that matter both are almost essential for an ordinary stamper battery1 and will certainly increase the crushing capacity and do better work from the greater regularity of the feed4 ,a #aj h4-p4 7nominal7 engine of good type is sufficient for ,huntingdon mill1 rock breaker1 self-feeder and steam pump4 ,a five-foot mill under favourable circumstances will crush about as much as eight head of medium weight stamps4 ,the ,grusonwek ,ball ,mills1 made by ,krupp of ,germany1 also that made by the ,austral ,otis ,company1 ,melbourne1 are fast and excellent crushing triturating appliances for either wet or dry working1 but are specially suited only for ores when the gold is fine and evenly distributed in the stone4 ,the trituration is effected by revolving the stone in a large cylinder together with a number of steel balls of various sizes1 the attrition of which with the rock quickly grinds it to powder of any required degree of fineness4 ,more mines have been ruined by bad mill management probably than by bad mining1 though every experienced man must have seen in his time many most flagrant instances of bungling in the latter respect4 ,shafts are often sunk on the wrong side of the lode or too near or too far away therefrom1 while instances have not been wanting where the 7mis7 manager has1 after sinking his shaft1 driven in the opposite direction to that where the lode should be found4 ,a common error is that of erecting machinery before there is sufficient ore in sight to make it certain that enough can be provided to keep the plant going4 ,in mines at a distance from the centre of direction it is almost impossible to check mistakes of this description1 caused by the ignorance or over sanguineness of the mine superintendent1 and they are often as disastrous as they are indefensible4 ,another fertile source of failure is the craze for experimenting with untried inventions1 alleged to be improvements on well-known methods4 ,a rule in the most scientific of card games1 whist1 is when in doubt lead trumps4 ,it might be paraphrased for mining thus3 ,when in doubt about machinery use that which has been proved4 ,let some one else do the experimenting4 ,the success of a quartz mine depends as much on favourable working conditions as on its richness in gold4 ,thus it may be that a mine carrying #e or #f oz4 of gold to the ton but badly circumstanced as to distance1 mountainous roads1 lack of wood and water1 in some cases a plethora of the latter1 or irregularly faulted country1 may be less profitable than another showing only #e or #f dwt41 but favourably situated4 ,it is usually desirable to choose for the battery site1 when possible1 the slope of a hill which consists of rock that will give a good foundation for your battery4 ,the economical working depends greatly on the situation1 which is generally fixed more or less1 in the proximity of the water4 ,the advantages of having ample water for battery purposes1 or of using water as a motive power1 are so great that it is very often desirable to construct a tramway of considerable length1 when1 by so doing1 that power can be utilised2 hence most quartz mills are placed near streams1 or in valleys where catchment dams can be effectively constructed1 except1 of course1 in districts where much water has to be pumped from the mine4 ,if water-power can be used1 the water-motor will necessarily be placed as low as possible1 in order to obtain the fullest available power4 ,one point is essential4 ,special care must be taken to keep the appliances above the flood-level4 ,if the water in the stream is not sufficient to carry off the tailings1 the battery should be placed at such a height as to leave sufficient slope for tailings' dumps4 ,this is more important when treating ore of such value that the tailings are worth saving for secondary treatment4 ,in this case provision should be made for tailings1 dams1 or slime pits4 ,whether the battery is worked by water1 steam1 or gas power1 an ample supply of water is absolutely necessary1 at least until some thoroughly effective mode of dry treatment is established4 ,if it can be possibly arranged the water should be brought in by gravitation1 and first cost is often least cost2 but where this is impossible1 pumps of sufficient capacity1 not only to provide the absolute quantity used1 but to meet any emergency1 should be erected4 ,the purer the water the better it will be for amalgamating purposes1 and in cold climates it is desirable to make provision for heating the water supplied to the battery4 ,this can be done by means of steam from the boiler led through the feed tanks2 but where the boiler power is not more than required1 waste steam from the engine may be employed1 but care must be taken that no greasy matter comes in contact with the plates4 ,the exhaust steam from the engine may be utilised by carrying it through tubes fitted in an ordinary #djj gallon tank4 ,reducing appliances have often to be placed in districts where the water supply is insufficient for the battery4 ,when this is so every available means must be adopted for saving the precious liquid1 such as condensing the exhaust steam from the engine4 ,this may be done by conducting it through a considerable length of ordinary zinc piping1 such as is used for carrying the water from house roofs4 ,also tailings pits should be made1 in which the tailings and slimes are allowed to settle1 and the cleared water is pumped back to be again used4 ,these pits should1 where practicable1 be cemented4 ,it is usual1 also1 to have one or two tailings dams at different levels2 the tailings are run into the upper dam1 and are allowed to settle2 the slimes overflow from it into the lower dam1 and are there deposited1 while the cleared water is pumped back to the battery4 ,arrangements are made by which all these reservoirs can be sluiced out when they are filled with accumulated tailings4 ,it is well not to leave the sluicing for too long a period1 as when the slimes and tailings are set hard they are difficult to remove4 ,where a permanent reducing plant is to be erected1 whatever form of mill may be adopted1 it is better for many reasons to use automatic ore feeders4 ,of these the best two ,i have met are the ,tulloch and ,challenge either of which can be adapted to any mill and both do good work4 ,by their use the reducing capacity of the mill is increased1 and the feeding being regular the wear and tear is decreased1 while by the regulated feeding of the pulp in the battery box or mortar can be maintained at any degree of consistency which may be found desirable1 and thus the process of amalgamation will be greatly facilitated4 ,the only objection which can be urged against the automatic feeder is that the steel points of picks1 gads1 drills1 and other tools may be allowed to pass into the mortar or mill1 and thus cause considerable wear and tear4 ,this1 ,i think1 can be avoided by the adoption of the magnet device1 described in ,rules of ,thumb4 ,there are many mines where #c to #d dwt4 of gold cover all the cost1 the excess being clear profit4 ,in fact there are mines which with a yield of #a #a_/b to #b dwt4 a ton1 and crushing with water power1 have actually yielded large profits4 ,on the other hand1 mines which have given extraordinary trial crushings have not paid working expenses4 ,everything depends on favourable local conditions and proper management4 ,having decided what class of crushing machinery you will adopt1 the first point is to fix on the best possible site for its erection4 ,this requires much judgment1 as success or failure may largely depend on the position of your machinery4 ,one good rule is to get your crusher as reasonably high as possible1 as it is cheaper to pump your feed water a few feet higher so as to get a good clear run for your tailings1 and also to give you room to erect secondary treatment appliances1 such as concentrators and amalgamators below your copper plates and blanket strakes4 ,next1 and this is most important1 see that your foundations are solid and strong4 ,a very large number of the failures of quartz milling plants is due to neglect of this rule4 ,i once knew a genius who erected a #aj-,lead mill in a new district1 and who adopted the novel idea of placing a bed log laterally beneath his stampers4 ,the log was laid in a little cement bed which1 when the battery started1 was not quite dry4 ,the effect was comical to every one but the unfortunate owners4 ,it was certainly the liveliest1 but at the same time one of the most ineffective batteries ,i have seen4 ,in a stamp mill the foundations are usually made of hard wood logs about #e to #f feet long1 set on end1 the bottom end resting on rock and set round with cement concrete4 ,these are bolted together1 and the box or mortar is bolted to them4 ,the horizontal logs to carry the horses or supports for the battery frame should also be of good size1 and solidly and securely bolted4 ,the same applies to your engine-bed1 but whether it be of timber1 or mason work1 above all things provide that the whole of your work is set out square and true to save after-wear and friction4 ,considerable difference of opinion exists as to the most effective weight for stamps4 ,my experience has been that this largely depends on the nature of your rock1 as does also the height for the drop4 ,i have usually found that with medium stamps1 say #g to #g #a_/b cwt4 with fair drop and lively action1 about #hj falls per minute1 the best results were obtained1 but the tendency of modern mill men is towards the heavier stamps1 #i cwt4 and even heavier4 ,to find the horse-power required to drive a battery1 multiply the weight of one stamp by the number of stamps in the battery2 the height of lift in feet by the number of lifts per minute2 add one-third of the product for friction1 and the result will be the number of feet-lbs4 per minute2 divide this by #cc1jjj which is the number of feet-lbs4 per minute equal to #a h4-p4 and the result will be the h4-p4 required4 ,thus if a stamp weighs #hjj lb4 and you have five in the box1 and each stamp has a lift of #i in4 #j4ge ft4 and strikes #hj blows per minute1 then #hjj x #e x #j4ge x #hj #bdj1jjj2 one-third of #bdj1jjj #hj1jjj which added to #bdj1jjj #cbj1jjj2 and #cbj1jjj divided by #cc1jjj #i4g h4-p4 or #a4i h4-p4 each stamp4 ,the total weight of a battery1 including stamper box1 stampers1 etc41 may be roughly estimated at about #a ton per stamp4 ,medium weight stampers1 including shank cam1 disc1 head1 and shoe1 weigh from #fjj to #gjj lb41 and need about #c_/d h4-p4 to work them4 ,the quantity of water required for the effective treatment of gold-bearing rock in a stamper battery varies according to the composition of the material to be operated upon1 but generally it is more than the inexperienced believe4 ,for instance1 mullocky lode stuff1 containing much clayey matter or material carrying a large percentage of heavy metal1 such as titanic iron or metallic sulphides1 will need a larger quantity of water per stamp than clean quartz4 ,a fair average quantity would be #gej to #ajjj gallons per hour for each box of five stamps4 ,in general practice ,i have seldom found #ajjj gallons per hour more than sufficient4 ,as to the most effective mesh for the screen or grating no definite rule can be given1 as that depends so largely on the size of the gold particles contained in the gangue4 ,the finer the particles the closer must be the mesh1 and nothing but careful experiment will enable the battery manager to decide this most important point4 ,the ,american slotted screens are best2 they wear better than the punched gratings and can be used of finer gauge4 ,woven steel wire gauze is employed with good effect in some mills where especially fine trituration is required4 ,this class of screen requires special care as it is somewhat fragile1 but with intelligent treatment does good work4 ,the fall or inclination of the tables1 both copper and blanket strakes1 is also regulated by the class of ore4 ,if it should be heavy then the fall must be steeper4 ,a fair average drop is #c_/d inch to the foot4 ,be careful that your copper tables are thoroughly water-tight1 for remember you are dealing with a very volatile metal1 quicksilver2 and where water will percolate mercury will penetrate4 ,the blanket tables are simply a continuation of the mercury tables1 but covered with strips of coarse blanket1 green baize1 or other flocculent material1 intended to arrest the heavier metallic particles which1 owing to their refractory nature1 have not been amalgamated4 ,the blanket table is1 however1 a very unsatisfactory concentrator at best1 and is giving place to mechanical concentrators of various descriptions4 ,an ancient ,egyptian gold washing table was used by the ,egyptians in treating the gold ores of ,lower ,egypt4 ,the ore was first ground1 it is likely by means of some description of stone arrasts and then passed over the sloping table with water1 the gold being retained in the riffles4 ,in these the material would probably be mechanically agitated4 ,although for its era ingenious it will be plain to practical men that if the gold were fine the process would be very ineffective4 ,possibly1 but of this ,i have no evidence1 mercury was used to retain the gold on the riffles1 as previously stated4 ,this method of saving the precious metal was known to the ancients4 ,at a mine of which ,i was managing director the lode was almost entirely composed of sulphide of iron1 carbonate of lime or calcspar1 with a little silica4 ,in this case it has been found best to crush without mercury1 then run the pulp into pans1 where it is concentrated4 ,the concentrates are calcined in a common reverberatory furnace1 and afterwards amalgamated with mercury in a special pan1 the results as to the proportion of gold extracted being very satisfactory2 but it does not therefore follow that this process would be the most suitable in another mine where the lode stuff1 though in some respects similar1 yet had points of difference4 ,i was lately consulted with respect to the treatment of a pyritic ore in a very promising mine1 but could not recommend the above treatment1 because though the pyrites in the gangue was similar1 the bulk of the lode consisted of silica1 consequently there would be a great waste of power in triturating the whole of the stuff to what1 with regard to much of it1 would be an unnecessary degree of fineness4 ,i am of opinion that in cases such as this1 where it is not intended to adopt the chlorination or cyanogen process1 it will be found most economical to crush to a coarse gauge1 concentrate1 calcine the concentrates1 and finally amalgamate in some suitable amalgamator4 ,probably for this mode of treatment ,krom rolls would be found more effective reducing agents than stampers1 as with them the bulk of the ore can be broken to any required gauge and there would consequently be less loss in slimes4 ,the great art in effective battery work is to crush your stuff to the required fineness only1 and then to provide that each particle is brought into contact with the mercury either in box1 trough1 plate1 or pan4 ,to do this the flow of water must be carefully regulated2 neither so much must be used as to carry the stuff off too quickly nor so little as to cause the troughs and plates to choke4 ,in cold weather the water may be warmed by passing the feed-pipe through a tank into which the steam from the engine exhausts1 and this will be found to keep the mercury bright and lively4 ,but be careful no engine oil or grease mingles with the water1 as grease on the copper tables will absolutely prevent amalgamation4 ,the first point1 then1 is to crush the gangue effectively1 the degree of fineness being regulated by the fineness of the gold itself4 ,this being done1 then comes the question of saving the gold4 ,if the quartz be clean1 and the gold unmixed with base metal1 the difficulty is small4 ,all that is required is to ensure that each particle of the ,royal metal shall be brought into contact with the mercury4 ,the main object is to arrest the gold at the earliest possible stage2 therefore1 if you are treating clean stone containing free gold1 either coarse or fine1 ,i advise the use of mercury in the boxes1 for the reason that a considerable proportion of the gold will be caught thereby1 and settling to the bottom1 or adhering to amalgamated plates in the boxes1 where such are used1 will not be afterwards affected by the crushing action1 which might otherwise break up1 or flour1 the mercury4 ,on the whole1 ,i rather favour the use of mercury in the box at any time1 unless the ore is very refractory--that is1 contains too great a proportion of base metals1 particularly sulphides of iron1 arsenic1 etc41 when the result will not be satisfactory1 but may entail great loss by the escape of floured mercury carrying with it particles of gold4 ,here only educated intelligence1 with experience1 will assist the battery manager to adopt the right system4 ,the crushed stuff--generally termed the pulp--passes from the boxes through the screens or gratings1 and so on to the tables--i4e41 sheets of copper amalgamated on the upper surface with mercury1 and sometimes electroplated with silver and afterwards treated with mercury4 ,unless the quartz is very clean1 and1 consequently light1 ,i am opposed to the form of stamper box with mercury troughs cast in the lip1 nor do ,i think that a trough under the lip is a good arrangement1 as it usually gets so choked and covered with the heavy clinging base metals as to make it almost impossible for the gold to come in contact with the mercury4 ,it will be found better where the gold is fine1 or the gangue contains much base metal1 to run the pulp from the lip of the battery into a distributor4 ,the distributor is a wooden box the full width of the mortar1 having a perforated iron bottom set some three to four inches above the first copper plate1 which should come up under the lip4 ,the effect of this arrangement is that the pulp is dashed on the plate by the falling water1 and the gold at once coming in contact with the mercury begins to accumulate and attract that which follows1 till the amalgam becomes piled in little crater-shaped mounds1 and thus #ge per cent of the gold is saved on the top plate4 ,i have tried a further adaptation of this process when treating ores containing a large percentage of iron oxide1 where the bulk of the gold is impalpably fine1 and contained in the gossan4 ,at the end of the blanket table1 or at any point where the crushed stuff last passes before going to the tailings heap1 or sludge pit1 a saver is placed4 ,the saver is a strong box about #ae in4 square by #c ft4 high1 one side of which is removable1 but must fit tight4 ,nine slots are cut inside at #d in4 apart1 and into these are fitted nine square perforated copper plates1 having about eighty to a hundred #a_/d in4 holes in each2 the perforations should not come opposite each other4 ,these plates are to be amalgamated on both sides with mercury1 in which a very little sodium has been placed 7if acid ores are being treated1 zinc should be employed in place of sodium1 and to prevent the plates becoming bare1 if the stuff is very poor1 thick zinc amalgam may be used with good effect2 but in that case discontinue the sodium1 and occasionally1 if required1 say once or twice in the day1 mix an ounce of sulphuric acid in a quart of water and slowly pour it into the launder above the saver74 ,underneath the saver you require a few riffles1 or troughs1 to catch any waste mercury1 but if not overfed there should be no waste4 ,this simple appliance1 which is automatic and requires little attention1 will sometimes arrest a considerable quantity of gold4 ,we now come to the subsidiary processes of battery work1 the cleaning of plates1 and scaling same when it is desired to get all the gold off them1 the cleaning and retorting of amalgam1 and of the mercury1 smelting gold1 etc4 ,plates should be tenderly treated1 kept as smooth as possible1 and when cleaning up after crushing1 in your own battery1 the amalgam--except1 say1 at half-yearly intervals--should be removed with a rubber only2 the rubber is simply a square of black indiarubber or soft pine wood4 ,when crushing rich ore1 and you want to get nearly all the gold off your plates1 the scraper may be resorted to4 ,this is usually made by the mine blacksmith from an old flat file which is cut in half1 the top turned over1 beaten out to a sharp blade1 and kept sharp by touching it up on the grinding-stone4 ,this1 if carefully used1 will remove the bulk of the amalgam without injury to the plate4 ,various methods of scaling plates will be found among ,rules of ,thumb4 ,where base metals are present in the lode stuff frequent retortings of the mercury1 say not less than once a month1 will be found to have a good effect in keeping it pure and active4 ,for this purpose1 and in order to prevent stoppage of the machinery1 a double quantity is necessary1 so that half may be used alternately4 ,less care is required in retorting the mercury than in treating the amalgam1 as the object in the one case is more to cleanse the metal of impurities than to save gold1 which will for the most part have been extracted by squeezing through the chamois leather or calico4 ,a good strong heat may therefore at once be applied to the retort and continued1 the effect being to oxidise the arsenic1 antimony1 lead1 etc41 which1 in the form of oxides1 will not again amalgamate with the mercury1 but will either lie on its surface under the water1 into which the nozzle of the retort is inserted1 or will float away on the surface of the water4 ,i have also found that covering the top of the mercury with a few inches of broken charcoal when retorting has an excellent purifying effect4 ,in retorting amalgam1 much care and attention is required4 ,first1 never fill the retort too full1 give plenty of room for expansion2 for1 when the heat is applied1 the amalgam will rise like dough in an oven1 and may be forced into the discharge pipe1 the consequence being a loss of amalgam or the possible bursting of the retort4 ,next1 be careful in applying the heat1 which should be done gradually1 commencing at the top4 ,this is essential to prevent waste and to turn out a good-looking cake of gold1 which all battery managers like to do1 even if they purpose smelting into bars4 ,sometimes special difficulties crop up in the process of separating the gold from the amalgam4 ,at the first cleaning up on the ,frasers ,mine at ,southern ,cross1 ,west ,australia1 great consternation was excited by the appearance of the retorted gold1 which1 as an old miner graphically put it1 was as black as the hind leg of a crow1 and utterly unfit for smelting1 owing to the presence of base metals4 ,some time after this ,i was largely interested in the ,blackborne mine in the same district when a similar trouble arose4 ,this ,i succeeded in surmounting1 but a still more serious one was too much for me--i4e41 the absence of payable gold in the stone4 ,i give here an extract from the ,australian ,mining ,standard1 of ,december #ith1 #ahic1 with reference to the mode of cleaning the amalgam which ,i adopted4 ,,new ,,method ,,of ,,separating ,,gold ,,from ,,impure ,,amalgam4 ,i had submitted to me lately a sample of amalgam from a mine in ,west ,australia which amalgam had proved a complete puzzle to the manager and amalgamator4 ,the ,mint returns showed a very large proportion of impurity1 even in the smelted gold4 ,when retorted only1 the ,mint authorities refused to take it after they had treated two cakes1 one of #aai oz41 which yielded only #ce oz4 #e dwt4 standard gold1 and one of #adj oz41 which gave #da oz4 #aj dwt4 ,the gold smelted on the mine was nearly as bad proportionately4 ,thus1 #abh oz4 smelted down at the ,mint to #hg oz4 #h dwt4 and #aji oz4 to #ee oz4 #aj dwt4 ,the impurity was principally iron1 a most unusual thing in my experience1 and was due to two causes revealed by assay of the ore and analysis of the mine water1 viz41 an excess of arsenate of iron in the stone1 and the presence in large proportions of mineral salts1 principally chloride of ,calcium ,ca,cl41 sodium ,na,cl1 and magnesium ,mg,cl#b1 in the mine water used in the battery4 ,the exact analysis of the water was as follows3-- ,carbonate of ,iron ,fe,c,o#c #b4gf grains per gallon ,carbonate of ,calcium ,ca,c,o#c #g4fa grains per gallon ,sulphate of ,calcium ,ca,s,o#d #ha4ga grains per gallon ,chloride of ,calcium ,ca,cl#b #bgig4hd grains per gallon ,chloride of ,magnesium ,mg,cl#b #faj4ac grains per gallon ,chloride of ,sodium or ,common ,salt ,na,cl #ejgb4fe grains per gallon ,total solid matter #hegb4gj #ai4e oz4 to the gallon4 ,it will be seen1 then1 that this water is nearly four times more salt that that of the sea4 ,the effect of using a water of this character1 as ,i have previously found1 is to cause the amalgamation of considerable quantities of iron with the gold as in this case4 ,i received #aj oz4 of amalgam1 and having found what constituted its impurities proceeded to experiment as to its treatment4 ,when retorted on the mine it was turned out in a black cake so impure as almost to make it impossible to smelt properly4 ,i found the same result on first retorting1 and after a number of experiments which need not be recapitulated though some were fairly effective1 ,i hit on the following method1 which was found to be most successful and will probably be so found in other localities where similarly unfavourable conditions prevail4 ,i took a small ball of amalgam1 placed it in a double fold of new fine grained calico1 and after soaking in hot water put it under a powerful press4 ,the weight of the ball before pressing was #aehc gr4 ,from this #chc gr4 of mercury was expressed and five-eighths of a grain of gold was retorted from this expressed mercury4 ,the residue1 in the form of a dark1 grey1 and very friable cake1 was powdered up between the fingers and retorted1 when it became a brown powder2 it was afterwards calcined on a flat sheet in the open air2 result1 #eaj gr4 of russet-coloured powder4 ,smelted with borax1 the iron oxide readily separated with the slag2 result1 #caa gr4 gold #hga-ajjj fine2 a second smelting brought this up to #iad-ajjj fine4 ,proportion of smelted gold to amalgam1 one-fifth4 ,the principal point about this mode of treatment is the squeezing out of the mercury1 whereby the amalgam goes into the retort in the form of powder1 thus preventing the slagging of the iron and enclosure of the gold4 ,the second point of importance is thorough calcining before smelting4 ,of course it would be practicable1 if desired1 to treat the powder with hydrochloric acid1 and thus remove all the iron1 but in a large way this would be too expensive1 and my laboratory treatment1 though necessarily on a small scale1 was intended to be on a practical basis4 ,the amalgam at this mine was in this way afterwards treated with great success4 ,for the information of readers who do not understand the chemical symbols it may be said that ,fe,c,o#c is carbonate of iron2 ,ca,c,o#c is carbonate of calcium2 ,ca,s,o#d is sulphate of calcium2 ,ca,cl#b is chloride of calcium2 ,mg,cl#b is chloride of magnesium2 ,na,cl is chloride of sodium1 or common salt4 ,,chapter ,,vii ,,gold ,,extraction--,,secondary ,,processes ,,and ,,lixiviation ,before any plan is adopted for treating the ore in a new mine the management should very seriously and carefully consider the whole circumstances of the case1 taking into account the quantity and quality of the lode stuff to be operated on1 and ascertain by analysis what are its component parts1 for1 as before stated1 the treatment which will yield most satisfactory results with a certain class of gangue on one mine will sometimes1 even when the material is apparently similar1 prove a disastrous failure in another4 ,some time since ,i was glad to note that the manager of a prominent mine strongly discountenanced the purchase of any extracting plant until he was fully satisfied as to the character of the bulk of the ore he would have to treat4 ,it would be well for the pockets of shareholders and the reputation of managers1 if more of our mine superintendents followed this prudent and sensible course4 ,having treated on gold extraction with mercury by amalgamated plates and their accessories1 something must be said about secondary modes of saving in connection with the amalgamation process4 ,the operations described hitherto have been the disintegration of the gold-bearing material and the extraction therefrom of the coarser free gold4 ,but it must be understood that most auriferous lode stuff contains a proportion of sulphides of various metals1 wherein a part of the gold1 usually in a very finely divided state1 is enclosed1 and on this gold the mercury has no influence4 ,also many lodes contain hard heavy ferric ores1 such as titanic iron1 tungstate of iron1 and hematite1 in which gold is held4 ,in others1 again1 are found considerable quantities of soft powdery iron oxide or gossan1 and compounds such as limonite1 aluminous clay1 etc41 which1 under the action of the crushing mill become finely divided and float off in water as slimes1 carrying with them atoms of gold1 often microscopically small4 ,to save the gold in such matrixes as these is an operation which even the best of our mechanical appliances have not yet fully accomplished4 ,where there is not too great a proportion of base metals on which the solvent will act1 and when the material is rich enough in gold to pay for the extra cost of treatment1 chlorination or cyanisation are the best modes of extraction yet practically adopted4 ,presuming1 however1 that we are working by the amalgamation process1 and have crushed our stone and obtained the free gold1 the next requirement is an effective concentrator4 ,of these there are many before the public1 and some do excellent work1 but do not act equally well in all circumstances4 ,the first and most primitive is the blanket table1 previously mentioned2 but it can hardly be said to be very effective1 and requires constant attention and frequent changing and washing of the strips of blanket4 ,instead of blanket tables percussion tables are sometimes used1 to which a jerking motion is given against the flow of the water and pulp1 and by this means the heavier minerals are gathered towards the upper part of the table1 and are from thence removed from time to time as they become concentrated4 ,i have seen this appliance doing fairly good work1 but it is by no means a perfect concentrator4 ,another form of shaking table is one in which the motion is given sideways1 and this1 whether amalgamated1 or provided with small riffles1 or covered with blanket1 keeps the pulp lively and encourages the retention of the heavier particles1 whether of gold or base metals containing gold4 ,there has also been devised a rocking table the action of which is analogous to that of the ordinary miner's cradle4 ,this appliance1 working somewhat slowly1 swings on rockers from side to side1 and is usually employed in mills where1 owing to the complexity of the ore1 difficulties have been met with in amalgamating the gold4 ,riffles are provided and even very fine gold is sometimes effectively recovered by their aid4 ,the ,frue vanner will1 as a rule1 act well when the pulp is sufficiently fine4 ,it is really a adaptation of an old and simple apparatus used in ,china and ,india for washing gold dust from the sands of rivers4 ,the original consisted of an endless band of strong cloth or closely woven matting1 run on two horizontal rollers placed about seven feet apart1 one being some inches lower than the other4 ,the upper is caused to revolve by means of a handle4 ,the cloth is thus dragged upwards against a small stream of water and sand fed to it by a second man1 the first man not only turning the handle but giving a lateral motion to the band by means of a rope tied to one side4 ,chinamen were working these forerunners of the ,frue vanner forty years ago in ,australia1 and getting fair returns4 ,the ,frue vanner is an endless indiarubber band drawn over an inclined table1 to which a revolving and side motion is given by ingenious automatic mechanism1 the pulp being automatically fed from the upper end1 and the concentrates collected in a trough containing water in which the band is immersed in its passage under the table2 the lighter particles wash over the lower end4 ,the only faults with the vanner are--first1 it is rather slow2 and secondly1 though so ingenious it is just a little complicated in construction for the average non-scientific operative4 ,of pan concentrators there is an enormous selection1 the principle in most being similar--i4e41 a revolving muller1 which triturates the sand1 so freeing the tiny golden particles and admitting of their contact with the mercury4 ,the mistake with respect to most of these machines is the attempt to grind and amalgamate in one operation4 ,even when the stone under treatment contains no deleterious compounds the simple action of grinding the hard siliceous particles has a bad effect on the quicksilver1 causing it to separate into small globules1 which either oxidising or becoming coated with the impurities contained in the ore will not reunite1 but wash away in the slimes and take with them a percentage of the gold4 ,as a grinder and concentrator1 and in some cases as an amalgamator1 when used exclusively for either purpose1 the ,watson and ,denny pan is effective2 but although successfully used at one mine ,i know1 the mode there adopted would1 for reasons previously given1 be very wasteful in many other mines4 ,there is considerable misconception1 even among men with some practical knowledge1 as to the proper function of these secondary saving appliances2 and sometimes good machines are condemned because they will not perform work for which they were never intended4 ,it cannot be too clearly realized that the correct order of procedure for extracting the gold held in combination with base metals is--first1 reduction of the particles to a uniform gauge and careful concentration only2 next1 the dissipation1 usually by simple calcination1 of substances in the concentrates inimical to the thorough absorption of the gold by the mercury2 and lastly1 the amalgamation of the gold and mercury4 ,for general purposes1 where the gangue has not been crushed too fine1 ,i think the ,duncan pan will usually be found effective in saving the concentrates4 ,in theory it is an enlargement of the alluvial miner's tin dish1 and the motion imparted to it is similar to the eccentric motion of that simple separator4 ,the calcining may be effectively carried out in an ordinary reverberatory furnace1 the only skill required being to prevent over roasting and so slagging the concentrates2 or not sufficiently calcining so as to remove all deleterious constituents2 the subject1 however1 is fully treated in ,chapter ,,viii4 ,for amalgamating ,i prefer some form of settler to any further grinding appliance1 but ,i note also improvements in the rotary amalgamating barrel1 which1 though slow1 is1 under favourable conditions1 an effective amalgamator4 ,the introduction of steam under pressure into an iron cylinder containing a charge of concentrates with mercury is said to have produced good results1 and ,i am quite prepared to believe such would be the case1 as we have long known that the application of steam to ores in course of amalgamation facilitates the process considerably4 ,some seventeen years since ,i was engaged on the construction of a dry amalgamator in which sublimated mercury was passed from a retort through the descending gangue in a vertical cylinder1 the material thence falling through an aperture into a revolving settler1 the object being to save water on mines in dry country4 ,the model1 about quarter size1 was completed when my attention was called to an ,american invention1 in which the same result was stated to be attained more effectively by blowing the mercury spray through the triturated material by means of a steam jet4 ,i had already encountered a difficulty1 since found so obstructive by experimentalists in the same direction1 that is1 the getting of the mercury back into its liquid metallic form4 ,this difficulty ,i am now convinced can be largely obviated by my own device of using a very weak solution of sulphuric acid 7it can hardly be too weak7 and adding a small quantity of zinc to the mercury4 ,it is perfectly marvellous how some samples of mercury sickened or floured by bad treatment1 may be brought back to the bright limpid metal by a judicious use of these inexpensive materials4 ,thus it will probably be found practicable to crush dry and amalgamate semi-dry by passing the material in the form of a thin pasty mass to a settler1 as in the old ,south ,american arrastra1 and1 by slowly stirring1 recover the mercury1 and with it the bulk of the gold4 ,the following is from the ,australian ,mining ,standard1 and was headed ,amalgamation ,without ,overflow3 ,recent experiments at the ,ballarat ,school of ,mines have proved that a deliverance from difficulties is at hand from an unexpected quarter4 ,the despised ,chilian mill and ,wheeler pan1 discarded at many mines1 will solve the problem1 but the keynote of success is amalgamation without overflow4 ,dispense with the overflow and the gold is saved4 ,two typical mines--the ,great ,mercury ,proprietary ,gold ,mine1 of ,kuaotunu1 ,n4,z41 the other1 the ,pambula1 ,n4,s4,w4--have lately been conducting a series of experiments with the object of saving their fine gold in an economical manner4 ,the last and best trials made by these companies were at the ,ballarat ,school of ,mines1 where amalgamation without overflow was put to a crucial test1 in each case with the gratifying result that ninety-six per cent of the precious metal was secured4 ,what this means to the ,great ,mercury ,mine1 for instance1 can easily be imagined when it is understood that notwithstanding all the latest gold-saving adjuncts during the last six months #abfj tons of ore1 worth #dl4 #ags4 #aj #bc;d4 a ton1 have been put through for a saving of #al4 #is4 #a #bc;d4 only2 or in other words over two-thirds of the gold has gone to waste 7for the time being7 in the tailings1 and in the tailings at the present moment lie the dividends that should have cheered shareholders' hearts4 ,and now for the modus operandi1 which1 it must be remembered1 is not hedged in by big royalties to any one1 rights1 patent or otherwise4 ,the ore to be treated is first calcined1 then put through a rock-breaker or stamper battery in a perfectly dry state4 ,if the battery is used1 ordinary precautions1 of course1 must be taken to prevent waste1 or the dust becoming obnoxious to the workmen4 ,the ore is then transferred to the ,chilian mill and made to the consistency of porridge1 the quicksilver being added4 ,when the principal work of amalgamation is done 7experience soon teaching the amount of grinding necessary71 from the ,chilian mill the paste 7so to say7 is passed to a ,wheeler or any other good pan of a similar type1 when the gold-saving operation is completed4 ,this being an experiment in the same direction as my own1 ,i tried it on a small scale4 ,i calcined some very troublesome ore till it was fairly sweet1 triturated it1 and having reduced it with water to about the consistency of invalid's gruel1 put it into a little berdan pan made from a camp oven1 which ,i had used for treating small quantities of concentrates1 and from time to time drove a spray of mercury1 wherein a small amount of zinc had been dissolved1 into the pasty mass by means of a steam jet1 added about half an ounce of sulphuric acid and kept the pan revolving for several hours4 ,the result was an unusually successful amalgamation and consequent extraction--over ninety per cent4 ,steam--or to use the scientific term1 hydro-thermal action--has played such an important part in the deposition of metals that ,i cannot but think that under educated intelligence it will prove a powerful agent in their extraction4 ,about fourteen years ago ,i obtained some rather remarkable results from simply boiling auriferous ferro-sulphides in water4 ,there is in this alone an interesting1 useful1 and profitable field for investigation and experiment4 ,the most scientific and perfect mode of gold extraction 7when the conditions are favourable7 is lixiviation by means of chlorine1 potassium cyanide1 or other aurous solvent1 for by this means as much as #ih per cent of the gold contained in suitable ores can be converted into its mineral salt1 and being dissolved in water1 re-deposited in metallic form for smelting2 but lode stuff containing much lime would not be suitable for chlorination1 or the presence of a considerable proportion of such a metal as copper1 particularly in metallic form1 would be fatal to success1 while cyanide of potassium will also attack metals other than gold1 and hence discount the effect of this solvent4 ,the earlier practical applications of chlorine to gold extraction were known as ,mears' and ,plattner's processes1 and consisted in placing the material to be operated on in vats with water1 and introducing chlorine gas at the bottom1 the mixture being allowed to stand for a number of hours1 the minimum about twelve1 the maximum forty-eight4 ,the chlorinated water was then drawn off containing the gold in solution which was deposited as a brown powder by the addition of sulphate of iron4 ,great improvements on this slow and imperfect method have been made of late years1 among the earlier of which was that of ,messrs4 ,newbery and ,vautin4 ,they placed the pulp with water in a gaslight revolving cylinder1 into which the chlorine was introduced1 and atmospheric air to a pressure of #fj lb4 to the square inch was pumped in4 ,the cylinder with its contents was revolved for two hours1 then the charge was withdrawn and drained nearly dry by suction1 the resultant liquid being slowly filtered through broken charcoal on which the chloride crystals were deposited1 in appearance much like the bromo-chlorides of silver ore seen on some of the black manganic oxides of the ,barrier silver mines4 ,the charcoal1 with its adhering chlorides1 was conveyed to the smelting-house and the gold smelted into bars of extremely pure metal4 ,messrs4 ,newbery and ,vautin claimed for their process decreased time for the operation with increased efficiency4 ,at ,mount ,morgan1 when ,i visited that celebrated mine1 they were using what might be termed a composite adaptation process4 ,their chlorination works1 the largest in the world1 were putting through #aejj tons per week4 ,the ore as it came from the mine was fed automatically into ,krom roller mills1 and after being crushed and sifted to regulation gauge was delivered into trucks and conveyed to the roasting furnaces1 and thence to cooling floors1 from which it was conveyed to the chlorinating shed4 ,here were long rows of revolving barrels1 on the ,newbery-,vautin principle1 but with this marked difference1 that the pressure in the barrel was obtained from an excess of the gas itself1 generated from a charge of chloride of lime and sulphuric acid4 ,on leaving the barrels the pulp ran into settling vats1 somewhat on the ,plattner plan1 and the clear liquid having been drained off was passed through a charcoal filter1 as adopted by ,newbery and ,vautin4 ,the manager1 ,mr4 ,wesley ,hall1 stated that he estimated cost per ton was not more than #cjs41 and he expected shortly to reduce that when he began making his own sulphuric acid4 ,as he was obtaining over #d oz4 to the ton the process was paying very well1 but it will be seen that the price would be prohibitive for poor ores unless they could be concentrated before calcination4 ,the ,pollok process is a newer1 and stated to be a cheaper mode of lixiviation by chlorine4 ,it is the invention of ,mr4 ,j4 ,h4 ,pollok1 of ,glasgow ,university1 and a strong ,company was formed to work it4 ,with him the gas is produced by the admixture of bisulphate of sodium 7instead of sulphuric acid1 which is a very costly chemical to transport7 and chloride of lime4 ,water is then pumped into a strong receptacle containing the material for treatment and powerful hydraulic pressure is applied4 ,the effect is stated to be the rapid change of the metal into its salt1 which is dissolved in the water and afterwards treated with sulphate of iron1 and so made to resume its metallic form4 ,it appears1 however1 to me that there is no essential difference in the pressure brought to bear for the quickening of the process4 ,in each case it is an air cushion1 induced in the one process by the pumping in of air to a cylinder partly filled with water1 and in the other by pumping in water to a cylinder partly filled with air4 ,the process of extracting gold from lode stuff and tailings by means of cyanide of potassium is now largely used and may be thus briefly described3--,it is chiefly applied to tailings1 that is1 crushed ore that has already passed over the amalgamating and blanket tables4 ,the tailings are placed in vats1 and subjected to the action of solutions of cyanide of potassium of varying strengths down to #j4b per cent4 ,these dissolve the gold1 which is leached from the tailings1 passed through boxes in which it is precipitated either by means of zinc shavings1 electricity1 or to the precipitant4 ,the solution is made up to its former strength and passed again through fresh tailings4 ,when the tailings contain a quantity of decomposed pyrites1 partly oxidised1 the acidity caused by the freed sulphuric acid requires to be neutralised by an alkali1 caustic soda being usually employed4 ,when cleaning up1 the cyanide solution in the zinc precipitating boxes is replaced by clean water4 ,after careful washing in the box1 to cause all pure gold and zinc to fall to the bottom1 the zinc shavings are taken out4 ,the precipitates are then collected1 and after calcination in a special furnace for the purpose of oxidising the zinc1 are smelted in the usual manner4 ,the following description of an electrolytic method of gold deposition from a cyanide solution was given by ,mr4 ,a4 ,l4 ,eltonhead before the ,engineers' ,club of ,philadelphia4 ,a description of the process is as follows3--,the ore is crushed to a certain fineness1 depending on the character of the gangue4 ,it is then placed in leaching vats1 with false bottoms for filtration1 similar to other leaching plants4 ,a solution of cyanide of potassium and other chemicals of known percentage is run over the pulp and left to stand a certain number of hours1 depending on the amount of metal to be extracted4 ,it is then drained off and another charge of the same solution is used1 but of less strength1 which is also drained4 ,the pulp is now washed with clean water1 which leaches all the gold and silver out1 and leaves the tailings ready for discharge1 either in cars or sluiced away by water1 if it is plentiful4 ,the chemical reaction of cyanide of potassium with gold is as follows1 according to ,elsner3-- #b;,au #d,k,cy ,o ,h#b,o #b,k,au,cy#b #b,,kho4 ,that is1 a double cyanide of gold and potassium is formed4 ,all filtered solutions and washings from the leaching vats are saved and passed through a precipitating 'box' of novel construction1 which may consist either of glass1 iron or wood1 and be made in any shape1 either oval1 round1 or rectangular--if the latter1 it will be about #aj ft4 long1 #d ft4 wide and #a ft4 high--and is partitioned off lengthwise into five compartments4 ,under each partition1 on the inside or bottom of the 'box1' grooves may be cut a quarter-to a half-inch deep1 extending parallel with the partitions to serve as a reservoir for the amalgam1 and give a rolling motion to the solution as it passes along and through the four compartments4 ,the centre compartment is used to hold the lead or other suitable anode and electrolyte4 ,the anode is supported on a movable frame or bracket1 so it may be moved either up or down as desired1 it being worked by thumb-screws at each end4 ,the electrolyte may consist of saturated solutions of soluble alkaline metals and earth4 ,the sides or partitions of each compartment dip into the mercury1 which must cover the 'box' evenly on the bottom to the depth of about a half-inch4 ,amalgamated copper strips or discs are placed in contact with the mercury and extended above it1 to allow the gold and silver solution of cyanide to come in contact4 ,the electrodes are connected with the dynamo2 the anode of lead being positive and the cathode of mercury being negative4 ,the dynamo is started1 and a current of high amperage and low voltage is generated1 generally #ajj to #abe amperes1 and with sufficient pressure to decompose the electrolyte between the anode and the cathode4 ,as the gas is generated at the anode1 a commotion is created in the liquid1 which brings a fresh and saturated solution of electrolyte between the electrodes for electrolysis1 and makes it continuous in its action4 ,the solution of double cyanide of gold1 silver1 and potassium1 which has been drained from the leaching vats1 is passed over the mercury in the precipitating 'box' when the decomposition of the electrolyte by the electric current is being accomplished1 the gold and silver are set free and unite with the mercury1 and are also deposited on the plates or discs of copper1 forming amalgam1 which is collected and made marketable by the well known and tried methods4 ,the above solution is regenerated with cyanide of potassium by the setting free of the metals in the passage over the 'box4' ,in using this solution again for a fresh charge of pulp1 it is reinforced to the desired percentage1 or strengthened with cyanide of potassium and other chemicals1 and is always in good condition for continuing the operation of dissolving4 ,the potassium acting on the water of the solution creates nascent hydrogen and potassium hydrate2 the nascent hydrogen sets free the metals 7gold and silver71 which are precipitated into the mercury and form amalgam1 leaving hydrocyanic acid2 this latter combines with the potassium hydrate of the former reaction1 thus forming cyanide of potassium4 ,there are other reactions for which ,i have not at present the chemical formulas4 ,as the solution passes over the mercury1 the centre compartment of the 'box' is moved slowly longitudinally1 which spreads the mercury1 the solution is agitated and comes in perfect contact with the mercury1 as well as the amalgamated plates or discs of copper1 ensuring a perfect precipitation4 ,it is not always necessary to precipitate all the gold and silver from the solution1 for it is used over and over again indefinitely2 but when it is required1 it can be done perfectly and cheaply in a very short time4 ,no solution leached from the pulp1 containing cyanide of potassium1 gold and silver1 need be run to waste1 which is in itself an enormous saving over the use of zinc shavings when handling large quantities of pulp and solution4 ,some of the advantages the electro-chemical process has over other cyanide processes are3 ,its cleanliness1 quickness of action1 cheapness1 and large saving of cyanide of potassium by regeneration2 not wasting the solutions1 larger recovery of the gold and silver from the solutions2 the cost of recovery less2 the loss of gold1 silver1 and cyanide of potassium reduced to a minimum2 the use of caustic alkali in such quantity as may be desired to keep the cyanide solution from being destroyed by the solidity of the pulp1 and also sometimes to give warmth1 as a warm cyanide solution will dissolve gold and silver quicker than a cold one4 ,these caustic alkalies do not interfere with or prevent the perfect precipitation of the metals4 ,the bullion recovered in this process is very fine1 while the zinc-precipitated bullion is only about #gjj fine4 ,the gold and silver is dissolved1 and then precipitated in one operation1 which we know cannot be done in the 'chlorination process'2 besides1 the cost of plant and treatment is much less in the above-described process4 ,the electro-chemical process1 which ,i have hastily sketched will1 ,i think1 be the future cheap method of recovering fine or flour gold from our mines and waste tailings or ore dumps4 ,without going into details of cost of treatment1 ,i will state that with a plant of a capacity of handling #aj1jjj tons of pulp per month1 the cost should not exceed #hs4 per ton1 but that may be cheapened by labour-saving devices4 ,there being no expensive machinery1 a plant could be very cheaply erected wherever necessary4 ,,chapter ,,viii ,,calcination ,,or ,,roasting ,,of ,,ores ,the object of calcining or roasting certain ores before treatment is to dissipate the sulphur or sulphides of arsenic1 antimony1 lead1 etc41 which are inimical to treatment1 whether by ordinary mercuric amalgamation or lixiviation4 ,the effect of the roasting is first to sublimate and drive off as fumes the sulphur and a proportion of the objectionable metals4 ,what is left is either iron oxide1 gossan1 or the oxides of the other metals4 ,even lead can thus be oxidised1 but requires more care as it melts nearly as readily as antimony and is much less volatile4 ,the oxides in the thoroughly roasted ore will not amalgamate with mercury1 and are not acted on by chlorine or cyanogen4 ,to effect the oxidation of sulphur1 it is necessary not only to bring every particle of sulphur into contact with the oxygen of the air1 but also to provide adequate heat to the particles sufficient to raise them to the temperature that will induce oxidation4 ,no appreciable effect follows the mere contact of air with sulphur particles at atmospheric temperature2 but if the particles be raised to a temperature of #ejj degrees ,fahr41 the sulphur is oxidised to the gaseous sulphur dioxide4 ,the same action effects the elimination of the arsenic and antimony associated with gold and silver ores1 as when heated to a certain constant temperature these metals readily oxidise4 ,the science of calcination consists of the method by which the sulphide ores1 having been crushed to a proper degree of fineness1 are raised to a sufficient temperature and brought into intimate contact with atmospheric air4 ,it will be obvious then that the most effective method of roasting will be one that enables the particles to be thoroughly oxidised at the lowest cost in fuel and in the most rapid manner4 ,the roasting processes in practical use may be divided into three categories3 ,first or ,a ,process4--,roasting on a horizontal and stationary hearth1 the flame passing over a mass of ore resting on such hearth4 ,in order to expose the upper surface of the ore to contact with air the material is turned over by manual labour4 ,this furnace of the reverberatory type is provided with side openings by which the turning over of the ore can be manually effected1 and the new ore can be charged and afterwards withdrawn4 ,second or ,b ,process4--,roasting in a revolving hearth placed at a slight incline angle from the horizontal4 ,the furnace is of cylindrical form and is internally lined with refractory material4 ,it has projections that cause the powdered ore to be lifted above the flame1 and1 at a certain height1 to fall through the flame and so be rapidly raised to the temperature required to effect the oxidation of the oxidisable minerals which it is desired to extract4 ,the rate1 or speed1 of revolution of this revolving furnace obviously depends upon the character of the ore under treatment2 it may vary from two revolutions per minute down to one revolution in thirty minutes4 ,any kind of fuel is available1 but that of a gaseous character is stated to be by far the most efficient4 ,any ordinary cylinder of a length of #be ft41 and a diameter of #d ft4 #f in41 inclined #a ft4 #f in4 in its length1 will calcine from #bd to #dh tons per diem4 ,another form of rotating furnace is one in which the axis is horizontal4 ,it is much shorter than the inclined type1 and the feeding and removal of the ore is effected by the opening of a retort lid door provided at the side of the furnace4 ,openings provided at each end of the furnace permit the passage of the flame through it1 and the revolution of the furnace turns over the powdered ore and brings it into more or less sustained contact with the oxidising flame4 ,the exposure of the ore to this action is continued sufficiently long to ensure the more or less complete oxidation of the ore particles4 ,third or ,c ,process4--,in this process the powdered ore is allowed to fall in a shower from a considerable height1 through the centre of a vertical shaft up which a flame ascends2 the powdered ore in falling through the flame is heated to an oxidising temperature1 and the sulphides are thus depleted of their sulphur and become oxides4 ,another modification of this direct fall or shaft furnace is that in which the fall of the ore is checked by cross-bars or inclined plates placed across the shaft2 this causes a longer oxidising exposure of the ore particles4 ,when the sulphur contents of pyritous ores are sufficiently high1 and after the ore has been initially fired with auxiliary carbonaceous fuel1 it is unnecessary1 in a properly designed roasting furnace1 to add fuel to the ore to enable the heat for oxidation to be obtained4 ,the oxidation or burning of the sulphur will provide all the heat necessary to maintain the continuity of the process4 ,the temperature necessary for effecting the elimination of both sulphur and arsenic is not higher than that equivalent to dull red heat2 and provided that there is a sufficient mass of ore maintained in the furnace1 the potential heat resulting from the oxidation of the sulphur will alone be adequate to provide all that is necessary to effect the calcination4 ,,types ,,of ,,furnaces ,,of ,,the ,,different ,,classes ,,that ,,are ,,in ,,actual ,,use4 ,a ,,or ,,reverberatory ,,class4 ,the construction of this furnace has already been sufficiently described4 ,if the roasting is performed in a muffle chamber1 the arrangement employed by ,messrs4 ,leach and ,neal1 ,limited1 of ,derby1 and designed by ,mr4 ,b4 ,h4 ,thwaite1 ,c4,e41 can be advantageously employed in this furnace1 which is fired with gaseous fuel4 ,the sensible heat of the waste gases is utilised to heat the air employed for combustion2 and by a controllable arrangement of combustion1 a flame of over #ajj feet in length is obtained1 with the result that the furnace from end to end is maintained at a uniform temperature4 ,by this system1 and with gaseous fuel firing1 a very considerable economy in fuel and in repairs to furnace1 and a superior roasting effect1 have been obtained4 ,where the ordinary reverberatory hearth is fired with solid coal from an end grate1 the temperature is at its maximum near the firing end1 and tails off at the extreme gas outlet end4 ,the ores in this furnace should therefore be fed in at the colder end of the hearth and be gradually worked or rabbled forward to the firing end4 ,one disadvantage of the reverberatory furnace is the fact that it is impossible to avoid the incursion of air during the manual rabbling action1 and this tends to cool the furnace4 ,the cost of roasting1 to obtain the more or less complete oxidation1 or what is known in mining parlance as a sweet roast 7because a perfectly roasted ore is nearly odourless7 varies considerably1 the variation depending of course upon the character of the ore and the cost of labour and fuel4 ,there are several modifications of the reverberatory furnace in use1 designed mechanically to effect the rabbling4 ,one of the most successful is that known as the ,horse-shoe furnace4 ,in plan the hearth of the furnace resembles a horse-shoe4 ,the stirring of the ore over the hearth is effected by means of carriages fixed in the centre of the furnace and having laterally projecting arms1 carrying stirrers1 that move along the hearth and turn over the pulverised ore4 ,in operation1 half the carriages are traversing the furnace1 and half are resting in the cooling space1 so that a control over the temperature of the stirrers is established4 ,this furnace is stated to be more economical in labour than other mechanically stirred reverberatory furnaces1 and there is also said to be an economy in fuel4 ,usually the mechanical stirring furnaces give trouble and should be avoided1 but the horse-shoe type possesses qualifications worthy of consideration4 ,b4--,,the ,,revolving ,,cylinder ,,furnace4 ,of these the best known to me are3 ,the ,howell-,white1 the ,bruckner1 the ,thwaite-,denny1 and the ,molesworth4 ,the ,bruckner is a cylinder1 turning on the horizontal axis and carried by four rollers4 ,the batch of ore usually charged into the two charging hoppers weighs about four tons4 ,when the two charging doors are brought under the hopper mouth1 the contents of the hopper fall directly into the cylinder4 ,the ends or throats of the furnace are reduced just sufficiently to allow the flame evolved from a grated furnace to pass completely through the cylinder4 ,a characteristic size for this ,bruckner furnace is one having a length of #ab feet and a diameter of #f feet4 ,a furnace of this capacity will have an inclusive weight 7iron and brickwork7 of #ae tons4 ,the time of operation1 with the ,bruckner1 will vary with the character of the ore under treatment and the nature of the fuel employed4 ,four hours is the minimum and twelve hours should be the maximum time of operation4 ,by the addition of common salt with the batch of ore1 such of its constituents as are amenable to the action of chlorine are chlorinated as well as freed from sulphur4 ,where the ore contains any considerable quantity of silver which should be saved1 the addition of the salt is necessary as the silver is very liable to become so oxidised in the process of roasting as to render its after treatment almost impossible4 ,i know a case in point where an average of nearly five ounces of silver to the ton1 at that time worth #cjs41 was lost owing to ignorance on this subject4 ,had the ore been calcined with salt1 ,na,cl1 the bulk of this silver would have been amalgamated and thus saved4 ,it was the extraordinary fineness of the gold saved by amalgamation as against my tests of the ore by fire assay that put me on the track of a most indefensible loss4 ,the ,howell-,white ,furnace4--,this furnace consists of a cast iron revolving cylinder1 averaging #be feet in length and #d ft4 #d in4 in diameter1 which revolves on four friction rollers1 resting on truck wheels1 rotated by ordinary gearing4 ,the power required for effecting the revolution should not exceed four indicated horse-power4 ,the cylinder is internally lined with firebrick1 projecting pieces causing the powdered ore to be raised over the flame through which it showers1 and is thereby subjected to the influence of heat and to direct contact oxidation4 ,the inclination of the cylinder1 which is variable1 promotes the gradual descension of the ore from the higher to the lower end4 ,it is fed into the upper end1 by a special form of feed hopper1 and is discharged into a pit at the lower end1 from which the ore can be withdrawn at any time4 ,the gross weight of the furnace1 which is1 however1 made in segments to be afterwards bolted together1 is some ninety to one hundred tons4 ,the furnace is fired with coal on a grated hearth1 built at the lower end2 it is more economical both in fuel and in labour than an ordinary reverberatory furnace4 ,the ,thwaite-,denny ,revolving ,furnace4--,this new type of furnace1 which is fired with gaseous fuel1 is stated to combine the advantages of the ,stetefeldt1 the ,howell-,white1 and the ,bruckner4 ,it is constructed as follows3--,three short cylinders1 conical in shape and of graduated dimensions1 are superimposed one over the other1 their ends terminating in two vertical shafts of brickwork1 by which the three cylinders are connected4 ,the powdered ore is fed into the uppermost cylinder and gravitates through the series4 ,the highest cylinder is the largest in diameter1 the lowest the smallest4 ,the gas flame1 burnt in a ,bunsen arrangement1 enters the smallest end of the lowest cylinder and passes through it2 then returns through the series and the ore is reduced by the expulsion of its sulphur1 arsenic1 etc41 as it descends from the top to the bottom4 ,the top cylinder is made larger than the one below it and the middle cylinder is made larger than the lowest one in proportion to the increased bulk of gases and ore4 ,the powdered ore in descending through the cylinders is lifted up and showers through the flame1 falling in its descent a distance of over #ajjj feet4 ,by the time it reaches the bottom the ore is thoroughly roasted4 ,provision is made for the introduction of separate supplies of air and gas into each cylinder2 this enables the oxidising treatment to be controlled exactly as desired so as to effect the best results with all kinds of ore4 ,each cylinder is driven from its own independent gearing1 and the speed of each cylinder can be varied at will4 ,the output of this type of furnace1 the operations of which appear to be more controllable than those of similar appliances1 depends1 of course1 upon the nature of the ore1 but may be considered to range within the limits of twelve to fifty tons in twenty-four hours1 and the cost of roasting will vary from #bs4 #f;d4 to #ds4 per ton1 depending upon the quality of ore and of fuel4 ,the gaseous fuel generating system permits not only the absolute control over the temperature in the furnace1 but the use of the commonest kinds of coal1 and even charcoal is available4 ,the power required to drive the ,thwaite-,denny furnace is four indicated horse-power4 ,the ,molesworth ,furnace also is a revolving cylindrical appliance1 which1 to say the least of it1 is in many respects novel and ingenious4 ,it consists of a slightly cone-shaped1 cast-iron cylinder about fourteen feet long1 the outlet end being the larger to allow for the expansion of the gases4 ,internal studs are so arranged as to keep the ore agitated2 and spiral flanges convey it to the outlet end continually1 shooting it across the cylinder4 ,the cylinder is encased in a brick furnace4 ,the firing is provided from outside1 the inventor maintaining that the products of combustion are inimical to rapid oxidisation1 to specially promote which he introduces an excess of oxygen produced in a small retort set in the roof of the furnace and fed from time to time with small quantities of nitrate of soda and sulphuric acid4 ,ores containing much sulphur virtually calcine themselves4 ,i have seen this appliance doing good work4 ,the difficulties appeared to be principally mechanical4 ,there are other furnaces which work with outside heat1 but ,i have not seen them in action4 ,c4--,,shaft ,,type ,,of ,,furnace ,in one form of this furnace1 instead of allowing the ore to descend in a direct clear fall the descent is impeded by inclined planes placed at different levels in the height of the shaft1 the ore descending from one plane to the other4 ,the ,stetefeldt ,shaft ,furnace4--,although very expensive in first cost1 has many advantages4 ,no motive power is required and the structure of the furnace is of a durable character4 ,its disadvantages are3--,want of control1 and the occasionally imperfect character of the roasting originating therefrom4 ,three sizes of ,stetefeldt's furnaces are constructed3 ,the largest will roast from #dj to #hj tons per diem4 ,the intermediate will roast from #bj to #dj tons per diem4 ,the smallest will roast from #aj to #bj tons per diem4 ,a good furnace should bring down the sulphur contents even of concentrates so as to be innocuous to mercuric amalgamation4 ,the sulphur left in the ore should never be allowed to exceed two per cent4 ,a forty per cent pyritous or other sulphide ore should be roasted in a revolving furnace in thirty to forty minutes1 and without any auxiliary fuel4 ,for ordinary purposes a #dj-;foot chimney is adequate for furnace work2 such a chimney four feet square inside at the base1 tapering to #b' #f at the summit1 will require #ab1jjj red bricks1 and #aejj fire-bricks for an internal lining to a height of #ab feet from the base of the chimney shaft4 ,when second-hand ,lancashire or ,cornish boiler flues are available1 they make admirable and inexpensive chimneys4 ,the advantage of wrought-iron or steel chimneys lies in the convenience of removal and erection4 ,they should be made in sections of #bj feet long1 three steel wire guy-ropes attached to a ring1 riveted to a ring two-thirds of the height of the chimney1 and attached to holdfasts driven into the ground2 tightening couplings should be provided for each wire4 ,flue dust depositing chambers should be built in the line of the flues between the furnace and the chimney2 they consist simply of carefully built brick chambers1 with openings to enable workmen to enter and rapidly clear away the deposited matters4 ,the chambers1 three or four times the cross sectional area of the chimney flue1 and ten to twenty feet long1 can be built of brickwork1 set in cement2 the walls are provided with a cavity1 filled with sand or ,portland cement1 so that there will be no danger of the incursion of air4 ,in all furnace work the greatest possible precautions should be taken to prevent the least cracking of either joints or bricks4 ,it is surprising how much the inadequate draft of a good chimney is due to cracks or orifices in the flues2 and therefore a competent furnace-man should see to it that his flues are thoroughly sound1 and free from openings through which the air can enter499 99 ,for full details of the most recent improvements in the cyanide process and in other methods of extraction1 the reader is referred to ,dr4 ,t4 ,k4 ,rose's ,metallurgy of ,gold1 third edition4 ,,chapter ,,ix ,,motor ,,power ,,and ,,its ,,transmission ,it is unnecessary to describe methods by which power for mining purposes has been obtained--that is1 up to within the last five years--beyond a general statement1 that when water power has been available in the immediate locality of the mine1 this cheap natural source of power has been called upon to do duty4 ,steam has been the alternative agent of power production applied in many different ways1 but labouring under as many disadvantages1 chief of which are lack of water1 scarcity of fuel and cost of transit of machinery4 ,sometimes condensing steam-engines have been employed4 ,for the generation of steam the semi-portable and semi-tubular have been the type of boiler that has most usually been brought into service4 ,needless to say1 when highly mineralised mine water only is available the adoption of this class of boiler is attended with anything but satisfactory results4 ,recently1 however1 there is strong evidence that where steam is the power agent to be employed the water-tube type of boiler is likely to be employed1 and to the exclusion of all other forms of apparatus for the generation of steam4 ,the advantages of this type1 particularly the tubulous form 7or a small water tube71 made as it is in sections1 offers unrivalled facilities for transport service4 ,the heaviest parts need not exceed #c cwt4 in weight1 and require neither heavy nor yet expensive brickwork foundations4 ,,waterless ,,power4 ,the difficulties in finding water to drive a steam plant are often of such a serious character as to involve the abandonment of many payable mines2 therefore1 a motive power that does not require the aqueous agent will be a welcome boon4 ,it will be a source of gratification to many a gold-claim holder to know that practical science has enabled motive power to be produced without the necessity of water1 except a certain very small quantity1 which once supplied will not require to be renewed1 unless to compensate for the loss due to atmospheric evaporation4 ,any carbonaceous fuel1 such as1 say1 lignite1 coal1 or charcoal1 can be employed4 ,the latter can be easily produced by the method described in the ,chapter on ,rules of ,thumb1 or by building a kiln by piling together a number of trunks of trees1 or fairly large-sized branches1 cut so that they can be built up in a compact form4 ,the pile1 after being covered with earth1 is then lighted from the base1 and if there are no inlets for the air except the limited proportion required for the smouldering fire at the base1 the whole of the timber will be gradually carbonised to charcoal of good quality1 which is available for the waterless power plant4 ,the waterless power plant consists of two divisions3 ,first1 a gas generating plant2 secondly1 an internal combustion or gas engine in which the gas is burnt1 producing by thermo-dynamic action the motive power required4 ,the system known as the ,thwaite ,power ,gas ,system is not only practically independent of the use of water1 but its efficiency in converting fuel heat into work is so high that no existing steam plant will be able to compete with it4 ,the weight of raw timber1 afterwards to be converted into charcoal1 that will be required to produce an effective horse-power for one hour equals #g lb4 ,if coal is the fuel #a #a_/c lb4 per ,e4,h4,p4 for one hour's run4 ,if lignite is the fuel #b #a_/b lb4 per ,e4,h4,p4 for one hour's run4 ,the plant is simple to work1 and as no steam boiler is required the danger of explosions is removed4 ,no expensive chimney is necessary for the waterless power plant4 ,where petroleum oil can be cheaply obtained1 say for twopence per gallon1 one of the ,otto ,cycle ,oil ,engines1 for powers up to #bj indicated horse-power1 can be advantageously employed4 ,these engines have the advantage of being a self-contained power1 requiring neither chimney nor steam boiler1 and may be said to be a waterless power4 ,the objection is the necessity to rely upon oil as fuel1 and the dangers attending the storage of oil4 ,a good oil engine should not require to use more than a pint of refined petroleum per indicated horse-power working for one hour4 ,fortunately for the mining industry electricity1 that magic and mysterious agency1 has come to its assistance1 in permitting motive power to be transmitted over distances of even as much as #ajj miles with comparatively little loss of the original power energy4 ,given1 that on a coal or lignite field1 or at a waterfall1 #ajj horse-power is developed by the combustion of fuel or by the fall of water driving a turbine1 this power can be electrically transmitted to a mine or ,,group ,,of ,,mines1 say #ajj miles away1 with only a loss of some #cj horse-power4 ,for twenty miles the loss on transmission should not exceed #ae horse-power so that #gj and #he horse-power respectively are available at the mines4 ,no other system offers such remarkable efficiencies of power transmission4 ,the new ,multiphase ,alternating ,electric ,generating and ,power ,transmission ,system is indeed so perfect as to leave practically no margin for improvement4 ,the multiphase electric motor can be directly applied to the stamp battery and ore-breaker driving-shaft and to the shaft of the amalgamating pans4 ,,approximate ,,power ,,required ,,to ,,drive ,,the ,,machinery ,,of ,a ,,mine4 ,rock breaker #aj effective horse-power ,amalgamating pan #e effective horse-power ,grinding pan #f effective horse-power ,single stamp of #gej lb4 dropping #ij times per minute #a4be effective horse-power ,settlers #d effective horse-power ,ordinary hoisting lift #bj effective horse-power ,allow #aj per cent in addition for overcoming friction4 ,besides this electrical distribution power1 which should not cost more than three farthings per effective horse-power per hour1 the electrical energy can be employed for lighting the drives and the shafts of the mine4 ,the modern electrical mine lamps leave little to be desired4 ,also it is anticipated that once the few existing difficulties have been surmounted electric drilling will supplant all other methods4 ,electric power can be employed for pumping1 for shot firing1 for hauling1 and for innumerable purposes in a mine4 ,electricity lends itself most advantageously to so many and varied processes1 even in accelerating the influence of cyanide solutions on gold1 and in effecting the magnetic influence on metallic particles in separating processes2 while applied to haulage purposes1 either on aerial lines or on tram or railroads1 it is an immediate and striking success4 ,it is anticipated that in the near future the mines on the ,randt1 ,south ,africa1 will be electrically driven from a coalfield generating station located on the coalfields some thirty miles from ,johannesburg4 ,such a plant made up of small multiples of highly efficient machines will enable mine-owners to obtain a reliable power to any extent at immediate command and at a reasonable charge in proportion to the power used4 ,this wholesale supply of power will be a godsend to a new field1 enabling the opening up to be greatly expedited2 and no climatic difficulties1 such as dry seasons1 or floods1 need interfere with the regular running of the machinery4 ,the same system of power-generation at a central station is to be applied to supply power to the mines of ,western ,australia4 ,,chapter ,x ,,company ,,formation ,,and ,,operations ,all the world over1 the operation of winning from the soil and rendering marketable the many valuable ores and mine products which abound is daily becoming more and more a scientific business which cannot be too carefully entered into or too skilfully conducted4 ,the days of the dolly and windlass1 of the puddler1 cradle1 and tin dish1 are rapidly receding2 and mining1 either in lode or alluvial working1 is being more generally recognised as one of the exact sciences4 ,in the past1 mining has been carried on in a very haphazard fashion1 to which much of its non-success may be attributed4 ,but the dawn of better days has arrived1 and with the advent of schools of mines and technical colleges there will in future be less excuse for ignorance in this most important industry4 ,this chapter will be devoted to ,company formation and working1 in which mistakes leading to very serious consequences daily occur4 ,it is not necessary to go deeply into the question why1 in the mining industry more than any other1 it should be deemed desirable as a general rule to carry on operations by means of public ,companies1 but1 as a matter of fact1 few names can be mentioned of men who mine extensively single handed4 ,yet1 risky as it is1 mining can hardly be said to be more subject to unpreventable vicissitudes than1 say1 pastoral pursuits1 in which private individuals risk1 and often lose or make1 enormous sums of money4 ,however1 it is with ,mining ,companies we are now dealing1 and with the errors made in the formation and after conduct of these ,associations4 ,the initial mistake most often made is that sufficient working capital is not called up or provided in the floating of the ,company4 ,promoters trust to get sufficient from the ground forthwith to ensure further development2 the consequence being that1 as nearly #ii per cent of mining properties require a very considerable expenditure of capital before permanent profits can be relied on1 the inexperienced shareholders who started with inflated hopes of enormous returns and immediate dividends become disheartened and forfeit their shares by refusing to pay calls1 and thus many good properties are sacrificed4 ,in ,england1 the companies are often floated fully paid-up1 but the same initial error of providing too little money for the equipment and effective working of the mine is usually fallen into4 ,again1 far too many ,companies are floated on the report of some self-styled mining expert1 often a man1 who1 like the schoolmaster of the last century1 has qualified for the position by failing in every other business he has attempted4 ,these men acquire a few geological and mining phrases1 and by more or less skilfully interlarding these with statements of large lodes and big returns they supply reports seductive enough to float the most worthless properties and cause the waste of thousands of pounds4 ,but the trouble does not end here4 ,when the ,company is to be formed1 some lawyer1 competent or otherwise1 is instructed to prepare articles of association1 rules1 etc42 which1 three times out of four1 is accomplished by a liberal employment of scissors and paste4 ,such rules may1 or may not1 be suited to the requirements of the organisation4 ,generally no one troubles much about the matter1 though on these rules depends the future efficient working of the ,company1 and sometimes its very existence4 ,then ,directors have to be appointed1 and these are seldom selected because of any special knowledge of mining they may possess1 but as a rule simply because they are large shareholders or prominent men whose names look well in a prospectus4 ,these gentlemen forthwith engage a ,secretary1 usually on the grounds that he is the person who has tendered lowest1 to provide office accommodation and keep the accounts2 and not from any particular knowledge he has of the true requirements of the position4 ,the way in which some ,directors contrive to spend their shareholders' money is humorously commented on by a ,westralian paper which describes a great machinery consignment lately landed in the neighbourhood of the ,boulder ,kalgoorlie4 ,it would seem as if the purchaser had been let loose blindfold in a prehistoric material-founder's old iron yard1 and having bought up the whole stock1 had shipped it off4 ,the feature of the entire antediluvian show is the liberal allowance of material devoted to destruction4 ,massive kibbles1 such as were used in coal mines half a century ago1 are arranged alongside a winding engine1 built in the middle of the century1 and evidently designed for hauling the kibbles from a depth of #ajjj feet4 ,nothing less than horse-power will stir the trucks for underground use1 and their design is distinctly of the antique type4 ,the engine is built to correspond--of a kind that might have served to raise into position the pillars of ,baalbec1 and the mass of metal in it fairly raises a blush to the iron cheek of frailer modern constructions4 ,the one grand use to which this monster could be put would be to employ it as a kedge for the ,australian continent in the event of it dragging its present anchors and drifting down south1 but as modern mining machinery the whole consignment is worth no more than its value as scrap-iron1 which in its present position is a fraction or two less than nothing4 ,next1 a man to manage the mine has to be obtained1 and some one is placed in charge1 of whose capabilities the ,directors have no direct knowledge4 ,being profoundly ignorant of practical mining they are incompetent to examine him as to his qualifications1 or to check his mode of working1 so as to ascertain whether he is acting rightly or not4 ,all they have to rely on are some certificates often too carelessly given and too easily obtained4 ,finally1 quite a large proportion of the allottees of shares have merely applied for them with the intention of selling out on the first opportunity at a premium1 hence they have no special interest in the actual working of the mine4 ,now let us look at the prospects of the ,association thus formed4 ,the legal ,manager or ,secretary1 often a young and inexperienced man1 knows little more than how to keep an ordinary set of books1 and not always that4 ,he is quite ignorant of the actual requirements of the mine1 or what is a fair price to pay for labour1 appliances1 or material4 ,he cannot check the expenditure of the ,mining ,manager1 who may be a rogue or a fool or both1 for we have had samples of all sorts to our sorrow4 ,the ,directors are in like case4 ,even where the information is honestly supplied1 they cannot judge whether the work is being properly carried out or is costing a fair price1 and the ,mining ,manager is left to his own devices1 with no one to check him nor any with whom he can consult in specially difficult cases4 ,thus matters drift to the almost certain conclusion of voluntary or compulsory winding up2 and so many a good property is ruined1 and promising mines1 which have never had a reasonable trial1 are condemned as worthless4 ,but let us ask1 would any other business1 even such as are less subject to unforeseen vicissitudes than mining1 succeed under similar circumstances8 ,it is now very generally agreed that to the profitable development of mining new countries1 at all events1 must look mainly for prosperity1 while other industries are growing4 ,therefore1 we cannot too seriously consider how we may soonest make our mines successful4 ,what is the remedy for the unsatisfactory state of affairs we have experienced8 ,the answer is a more practical system of working from the inception4 ,although it may evoke some difference of opinion ,i consider it both justifiable and desirable that the ,state should take some oversight of mining matters1 at all events in the case of public ,companies4 ,it would be a salutary rule that the promoters of any mining undertaking should1 before they are allowed to place it on the market1 obtain and pay for the services of a competent ,government ,mining ,inspector1 who need not necessarily be a ,government officer1 but might1 like licensed surveyors1 be granted a certificate of competency either by a ,school of ,mines or by some qualified ,board of ,examiners4 ,the certificate of such ,inspector that the property was as represented1 should be given before the prospectus was issued4 ,it is arguable whether even further oversight might not be properly be taken by the ,state and the report of a qualified officer be compulsory that the property was reasonably worth the value placed upon it in the prospectus4 ,probably it will be contended that such restrictions would be an undue interference with private rights1 and the old aphorism about a fool and his folly will be quoted4 ,there are doubtless fools so infatuated that if they were brayed in a ten hundred-weight stamp-battery the foolishness that had not departed from them would give a highly payable percentage to the ton4 ,yet the ,state in other matters tries by numerous laws to protect such from their folly4 ,a man may not sell a load of wood without the certificate from a licensed weighbridge or a loaf of bread without1 if required1 having to prove its weight2 and we send those to gaol who practise on the credulity and cupidity of fools by means of the confidence trick4 ,why not1 therefore1 where interests which may be said to be national are involved1 endeavour to ensure fair dealing8 ,then with regard to the men who are to manage the mines1 seeing that a man may not become captain or mate of a river steamboat without some certificate on competency1 nor drive her engines before he has passed an examination to prove his fitness1 surely it is not too much to say that the mine manager or engineer1 to whose care are often confided the lives of hundreds of men1 and the expenditure of thousands of pounds1 should be required to obtain a recognised diploma to prove his qualifications4 ,the examinations might be made comparatively easy at first1 but afterwards1 when by the establishment of ,schools and ,mines the facilities have been afforded for men to thoroughly qualify1 the standard should be raised2 and after a date to be fixed no man should be permitted to assume the charge of a mine or become one of its officers without a proper certificate of competency from some recognised ,school of ,mines or ,technical ,college4 ,the effect of such a regulation would in a few years produce most beneficial results4 ,in ,new ,zealand1 whose progressive legislature ,i do not generally commend1 they have1 in the matter of mine management1 at all events1 taken a step in the right direction4 ,there a mine manager1 before he obtains his certificate1 must have served at least two years underground1 and has to pass through a severe examination1 lasting for days1 in all subjects relating to mining and machinery connected with mining4 ,in addition1 he must prove his capacity by making an underground survey1 and then plotting his work4 ,the examination is a stiff one1 as may be judged from the fact that between #ahhf and #ahia1 only #bg candidates passed4 ,then the conditions were made easier1 and from that date to #ahie1 #ai passed4 ,of the #df students who gained first-class honours1 #cj have left for ,south ,africa or ,australia1 in both of which countries ,new ,zealand certificated men are held in high estimation4 ,but returning to the formation of the ,company1 care should be taken in appointing ,directors that at least one member of the ,board is selected on account of his special technical knowledge of mining1 and others for their special business capacity4 ,the ornamental men with high sounding names should not be required in legitimate ventures4 ,also1 it is most important that the business ,manager or ,secretary should be a specially qualified man1 who by experience has learned what are the requirements of a mine doing a certain amount of work1 so that a proper check may be kept on the expenses4 ,the more ,companies such a ,secretary has the better1 as one qualified man can supervise a large staff of clerks1 who would themselves be qualifying for similar work1 and gaining a useful and varied experience of mining business4 ,an office of this description having charge of a large number of mines is1 in its way1 a technical school1 and lads trained therein would be in demand as mine pursers1 a very responsible and necessary officer in a big mine4 ,with respect to the men to whom the actual mining and treatment of ores and machinery is committed the greatest mistakes of the past have been that too much has been required from one man1 a combination not to be found probably in one man in a thousand4 ,such ,admirable ,crichtons are rare in any profession or business1 and that of mining is no exception4 ,men who profess too much are to be distrusted4 ,your best men are they who concentrate their energies and intellects in special directions4 ,the ,mining ,manager should1 if possible1 be chosen from men holding certificates of competency from some technical mining school and1 of course1 should1 in addition1 have some practical experience1 not necessarily as ,head ,manager4 ,he should understand practical mine surveying and calculation of quantities1 be able to dial and plot out his workings1 and prepare an intelligible plan thereof for the use of the ,directors1 and should understand sufficient of physics1 particularly pneumatics and hydraulics1 to ensure thoroughly efficient pumping operations without loss of power from unnecessarily heavy appliances4 ,any other scientific knowledge applicable to his business which he may have acquired will tell in his favour1 but he must1 above all things1 be a thoroughly practical man4 ,such men will in time be more readily procurable1 as boys who have passed through the various ,schools of ,mines will be sent to learn their business practically at the mines just as we now1 having given a lad a course of naval instruction1 send him to sea to learn the practical part of his life's work4 ,but1 of course1 more is wanted on a mine than a man who can direct the sinking of shafts1 driving of levels1 and stoping of the lode4 ,much loss and disappointment have resulted in the past from unsuitable1 ineffective1 or badly designed and erected machinery1 whether for working the mine or treating the ores4 ,to obviate this defect a first-class mining engineer is required4 ,then1 also1 day by day we are more surely learning that mining in all its branches is a science1 and that the treatment of ores and extraction of the metals is daily becoming more and more the work of the laboratory rather than of the rule-of-thumb procedure of the past4 ,every mine1 whether it be of gold1 silver1 tin1 copper1 or other metal1 requires the supervision of a thoroughly qualified metallurgist and chemist1 and one who is conversant with the newest processes for the extraction of the metals from their ores and matrices4 ,it has then been stated that to ensure effective working each mine requires1 in addition to competent directors1 a business manager1 mining-manager1 and assistants1 engineer1 chemist1 and metallurgist1 with assistant assayers1 etc41 all highly qualified men4 ,but it will be asked1 how are many struggling mines in sparsely populated countries to obtain the services of all these eminent scientists8 ,the reply is by co-operation4 ,one of the most ruinous mistakes of the past has been that each little mining venture has started on an independent course1 with different management1 separate machinery1 etc4 ,can it then be wondered at that our gold-mining is not always successful8 ,under a co-operative system all that each individual mine would require would be a qualified1 practical miner capable of opening and securing the ground in a miner-like manner1 and a good working engineer2 and in gold-mining1 where the gold is free in its matrix1 a professional amalgamator1 or lixiviator4 ,for the rest1 half a dozen or more mines may collectively retain the services of a mine manager of high attainments as general inspector and superintendent1 and the same system could be adopted with respect to an advising metallurgist and an engineer4 ,for gold1 as indeed for other metals1 a central extracting works1 where the ores could be scientifically treated in quantity1 might be erected at joint cost1 or might easily be arranged for as a separate business4 ,a very fruitful cause of failure is the fatuous tendency of directors and mine managers to adopt new processes and inventions simply because they are new4 ,as an inventor in a small way myself1 and one who is always on the watch for improved methods1 ,i do not wish to discourage intelligent progress2 but the greatest care should be exercised by those having the control of the money of shareholders in mining properties before adopting any new machinery or process4 ,we have seen1 and unfortunately shall see1 many a promising mining company brought to grief by this popular error4 ,the directors of mining companies might1 to use an ,american saying1 paste this in their hats as a useful and safe aphorism4 ,,let ,,others ,,do ,,the ,,experimenting2 ,,we ,,are ,,willing ,,to ,,pay ,,only ,,for ,,proved ,,improvements4 ,i can cordially endorse every word of the following extracts from ,messrs4 ,mc,dermott and ,duffield's admirable little work1 ,losses in ,gold ,amalgamation4 ,some directors of mining companies are naturally inclined to listen to the specious promises of inventors of novel processes and new machinery1 forgetting their own personal disadvantage in any argument on such matters1 and assuming a confidence in the logic of their own conclusions1 while they ignore the fruitful experience of thousands of practical men who are engaged in the mining business4 ,the repeated failures of directors in sending out new machinery to their mines ought by this time to be a sufficient warning against increasing risks that are at once natural and unavoidable1 and to deter them from plunging their shareholders into experiments which1 in ninety-nine cases out of a hundred1 result in nothing but excessive and needless expenses4 ,it is certain that new machines and new processes are1 and will be1 given attention by mining men in proportion to their probable merits2 but the proper place for experiments is in a mill already as successful as under known processes it can be made4 ,in a new enterprise1 even when the expense of an experiment is undertaken by the inventor1 the loss to the mine-owner in case of failure must be very great1 both in time and general running expenses4 ,directors should not believe that a willingness to risk cash in proving an invention is necessarily any proof of value of the same2 it is only a measure of the faith of the inventor1 which is hardly a safe standard to risk shareholders' money by4 ,the variety of modifications in approved processes ought at least to suggest the desirability of exhausting the known1 before drawing on the unknown and purely speculative4 ,it should also be borne in mind that what might appear at first sight to be new processes1 and even new machinery1 are1 in fact1 often nothing but old contrivances and plausible theories long ago exploded among practical men4 ,many mining companies have been ruined1 without any reference to their mines1 through men deciding on the reasonableness of new process and machinery who have no knowledge of the business in hand4 ,it is assumed often1 that if an inventor or manufacturer of new machinery will agree to guarantee success1 or take no pay if not successful1 the company takes no risk4 ,in actual fact a whole year is wasted in most cases1 failure spoils the reputation of the company1 running expenses have continued1 and further working capital cannot be raised1 because all concerned have lost confidence by the failure to obtain returns promised4 ,all this in addition to the regular1 unavoidable risks of mining itself1 which may1 at any moment during the year lost1 call for increased expenses and increased faith in ultimate success4 ,to the mining man who makes money by the business1 the natural risks of mining is all he will take2 it is sufficient2 and when he invests more money in machinery he takes good care that he takes no chances of either failure or delay4 ,the following are rules which no mining company or individual mine-owner can afford to neglect4 7#a7 ,the risk should be confined to mining4 ,no body of directors is justified in taking a shareholder's money and investing it in new processes or machinery when the subscription was simply for a mining venture4 ,directors are invariably incapable of deciding whether a so-called improvement in machinery or process is really so or not1 and the reasonable course is to follow established precedents4 7#b7 ,the risk of selecting an incompetent manager should be reduced to minimum by taking a man with a successful record in the particular work to be done4 ,the manager selected should be prohibited1 as much as the directors1 from experimenting with new methods or machinery4 ,a really experienced man will require no check in this direction1 as he will not risk ruining his reputation4 7#c7 ,the only time for a company to experiment is when the mine is paying well by the usual methods1 and the treasury is in a condition to speculate a little in possible improvements without jeopardising regular returns4 ,probably this is the best place to insert another word of warning to directors who are not mining specialists1 and also to investors in gold mining shares4 ,assays of auriferous lode material are almost invariably worthless as a guide in the real value of the stone in quantity4 ,the one way to decide this is by battery treatment in bulk1 and then only after many tons have been put through4 ,the reason is obvious4 ,first1 the prospector or company promoter1 if he knows it1 is not in the least likely to pick the worst piece of stone in the heap for assay2 and1 secondly1 even should the sample be selected with the sole object of getting a fair result1 no living man can judge the value of a gold lode by the result of treatment of an ounce of stone4 ,so when you see it stated that ,messrs4 ,oro and ,gildenstein1 the celebrated assayers1 have found that a sample of rock from the ,golden ,mint ,mine1 ,golconda1 assays at the rate of #b1edf oz4 #ac dwt4 and #ba gr4 to the ton1 and that there are thousands of tons of similar stone in sight1 the statement should be received with due caution4 ,the assay is doubtless correct1 but the deductions therefrom are most misleading4 ,a few words of advice also to directors of mine-purchasing companies and syndicates1 of which there are now so many in existence1 may probably be found of value4 ,it is not good policy as a general rule to buy entirely undeveloped properties1 unless such have been inspected by your own man1 who is both competent and trustworthy1 and who should have indeed an interest in the profits4 ,large areas1 although so popular in ,england1 do not compensate for large bodies of payable ore2 the most remunerative mine is generally one of comparatively small area1 but containing a large lode formation of payable but often low grade1 ore4 ,it is worse still1 of course1 to buy a practically worked out mine1 though this too is sometimes done4 ,it must be remembered that mining1 though often so profitable1 is nevertheless a destructive industry1 thus differing from agriculture1 which is productive1 and manufactures1 which are constructive4 ,every ton of stone broken and treated from even the best gold mine in the world makes that mine the poorer by one ton of valuable material2 thus1 to buy a mining property on its past reputation for productiveness is1 as a rule1 questionable policy1 unless you know there is sufficient good ore in sight to cover the purchase cost and leave a profit4 ,one of the greatest causes of non-success of gold-mining ventures1 particularly when worked by public companies1 is the lack of actual personal supervision1 and hence1 among other troubles1 is that ultra-objectionable one--gold stealing from the mills1 or1 in alluvial mining1 from the tail races4 ,as to the former1 the following appeared in #ahic in the ,london ,mining ,journal1 and is1 ,i think1 worthy of the close consideration of mine directors in all parts of the world3-- ,no one that has not experienced the evil of gold thieving from reduction mills can have any idea of the pernicious element it is1 and the difficulty1 once that it has got 'well hold1' of rooting it out4 ,it permeates every class of society in the district connected with the industry1 and managers1 amalgamators1 assayers1 accountants1 aye1 even bank officials1 are 'all on the job' to 'get a bit' while there is an opportunity4 ,to exterminate the hateful monster requires on the part of the mine proprietors combined1 stern and drastic measures undertaken under the personal supervision of one or more of their directors1 and in many instances necessitating the removal of the whole of the official staff4 ,the writer narrates how about twenty years ago he was led to suspect that in an ,australian mine running forty head of stamps1 in which he held a controlling interest1 the owners were being defrauded of about a fourth of the gold really contained in the ore1 and the successful steps taken to check the robbery4 ,we first of all dispensed with the services of the general manager1 and then issued the following instructions to the mine and mill managers1 ,i remaining at the mine to see them carried out until ,i substituted a practical local man as agent1 who afterwards carried on the work most efficiently3-- 7a7 ,both of these officials to keep separate books and accounts2 in other words1 to be distinct departments4 7b7 ,the ore formerly was all thrown together and put through the mill4 ,i subdivided it into four classes1 ,a1 ,b1 ,c1 and ,d1 representing deep levels north and upper levels north1 deep levels south and upper levels south1 and allotted to each class ten heads of stamps at the mill4 7c7 ,the mine manager to try three prospects1 forenoon and afternoon of each day1 from the dumps of each of the four classes and record in a book to be kept for that purpose the estimated mill yield of each one4 7d7 ,the mill manager was required to do the same at the mill and keep his record4 7e7 ,there were four underground bosses in each shift1 twelve in all4 ,i had a book fixed at the top of the shaft in which ,i required each of these men1 at the expiry of every shift1 to record any change in the faces of the quartz and particularly in regard to quality4 7f7 ,having divided the ore into four classes ,i instructed the amalgamators1 of which there were two in each shift1 six in all1 that ,i required the amalgam from each to be kept separate1 with the object of ascertaining what each part of the mine produced4 7g7 ,i procured padlocks for the covering boards of the mercury tables and gave the keys to the amalgamators with instructions that they were not to hand them over to any one except the exchange shift without my written authority1 and instructed them that they should clean down the plates every three hours1 and after cleaning down the amalgam1 buckets to be placed in the cleaning room1 which ,i instructed to be kept locked and the key in charge of the watchman night and day4 7h7 ,the whole of the amalgam taken from the plates during each twenty-four hours to be cleaned and squeezed by the two amalgamators on duty every forenoon at nine o'clock in the presence of the mill manager1 who should weigh each lot and enter it in a book to be kept for the purpose1 and the entry to be signed by the mill manager and both amalgamators as witnesses4 7i7 ,every alternate ,friday the mortars 7boxes7 to be cleaned out2 the work to be commenced punctually at eight ,a4,m4 by the six amalgamators in the presence of the mill manager1 assisted by the three amalgam cleaning room watchmen and the four battery feeders on duty1 prohibiting any of them from leaving until the cleaning up was finished1 and the amalgam cleaned1 squeezed and weighed1 and the amount entered by the mill manager in the record look and attested by the amalgamators4 ,i think the intelligent readers 7particularly those with a knowledge of the business7 will see the drift of the above regulations1 viz41 for there to be any peculation the whole of the battery staff--fourteen in all--would have to participate in it1 and the number was too many to keep a secret4 ,formerly the amalgam cleaning room was sacred to the mill manager1 and on announcing to that official the new instructions he at once tendered his resignation in a tone of offended dignity1 immediately followed by that of the mine manager4 ,it is a significant fact that shortly afterwards these two officials purchased a large mill and other property at a cost of ten thousand pounds1 and that the mine yielded for the following three years during which ,i was connected with it an average of over #ag dwt4 to the ton1 as against formerly #aj to #ab dwt4 ,the reader must draw his own conclusions4 ,i used to make it a practice to visit the mine daily and prospect the ore1 and having the mine and mill managers' daily prospecting as a guide as well as my own1 every man at the mill knew it was impossible for them to thieve without my detecting it2 moreover1 ,i made it a rule to discharge any of the mill employees that ,i discovered were interested in any small private claims4 ,the crux of the whole thing is having a practical miner at the head of affairs1 and it is impossible for him to thieve if the work is carried out in the manner ,i have described4 ,to bring the whole matter to a conclusion4 ,it may be taken as a safe axiom that to make gold mining in the mine as distinct from mining on the ,stock ,exchange really profitable the same system of economy1 of practical supervision1 and scientific knowledge which is now adopted in all other businesses must be applied to the raising and extraction of the metal4 ,then1 and not till then1 will genuine mining take the place to which it is entitled amongst our industries4 ,,chapter ,,xi ,,rules ,,of ,,thumb ,this chapter has been headed as above because a number of the rules and recipes given are simply practical expedients1 not too closely scientific4 ,my endeavour has been to supply practical and useful information in language as free from technicalities as possible1 so as to adapt it to the ordinary miner1 mill operator and prospector1 many of whom have had no scientific training4 ,some of the expedients are original devices educed by what we are told is the mother of inventions2 others are hints given by practical old prospectors who had met with difficulties which would be the despair of a man brought up within reach of forge1 foundry1 machine shop1 or tradesmen generally4 ,there are many highly ingenious and useful contrivances besides these ,i have given4 ,,living ,,places ,the health of the prospector1 especially in a new country1 depends largely on his housing--in which particular many men are foolishly careless1 for although they are aware that they will be camped out for long periods1 yet all the shelter they rely on is a miserable calico tent1 often without a fly1 while in some cases they sometimes even sleep on the wet1 or dusty1 ground4 ,such persons fully deserve the ill health which sooner or later overtakes them4 ,a little forethought and very moderate ingenuity would render their camp comparatively healthy and comfortable4 ,in summer the tent is the hottest1 and in winter the coldest of domiciles4 ,the pizie or adobie hut1 or1 where practicable1 the dugout1 are much to be preferred1 especially the latter4 ,pizie or adobie is simply surface soil kneaded with water and either moulded between boards like concrete1 to construct the walls1 or made into large sun-dried bricks4 ,salt water should not be used1 as it causes the wall to be affected by every change of weather4 ,a properly constructed house of this material1 where the walls are protected by overhanging eaves1 are practically everlasting1 and the former have been standing for centuries4 ,there are buildings of pizie or adobie in ,mexico1 ,california and ,australia which are as good as new1 although the latter were built nearly a century ago4 ,adobie dwellings are warm in winter and cool in summer1 and can be kept clean and healthy by occasional coatings of lime whitewash4 ,the dugout is even more simple in construction4 ,a cutting1 say ten feet wide1 is put into the base of a hill for say twelve feet until the back wall is1 say1 ten feet high1 the sides starting from nothing to that height4 ,the front and such portion as is required of the side walls are next constructed of pizie or rough stone1 with mud mortar1 and the roof either gabled or skillion of bough1 grass1 or reed thatch1 and covered with pizie1 over which is sometimes put another thin layer of thatch to prevent the pizie being washed away by heavy rain4 ,nothing can be more snug and comfortable than such a house1 unless the cows1 as ,mark ,twain narrates1 make things monotonous by persistently tumbling down the chimney4 ,when the ,burra copper mines were in full work in ,australia1 the banks of the ,burra ,creek were honeycombed like a rabbit warren with the dugout homes of the ,cornish miners4 ,the ruins of these old dugouts now extend for miles1 and look something like an uncovered ,pompeii4 ,when water is scarce and the tent has to be retained1 much can be done to make the camp snug4 ,i occupied a very comfortable camp once1 of which my then partner1 a ,dane1 was the architect4 ,we called it ,the ,bungalow1 and it was constructed as follows3 ,first we set up our tent1 #aj ft4 by #h ft41 formed of calico1 but lined with green baize1 and covered with a well set fly4 ,next we put in four substantial forked posts about #aj ft4 high and #ae ft4 apart1 with securely fixed cross pieces1 and on the top was laid a rough flat roof of brush thatch2 the sides were then treated in the same way1 but not so thickly1 being merely intended as a breakwind4 ,the tent with its two comfortable bunks was placed a little to one side1 the remaining space being used as a dining and sitting room all through the summer4 ,except in occasional seasons of heavy rain1 when we were saved the trouble of washing our dishes1 the tent was only used for sleeping purposes1 and as a storehouse for clothes and perishable provisions4 ,i have dwelt in marble halls since then1 but never was food sweeter or sleep sounder than in the old bush bungalow4 ,a ,,bush ,,bed ,to make a comfortable bush bedplace1 take four forked posts about #c ft4 #f in4 long and #b to #c in4 in diameter at the top2 mark out your bedplace accurately and put a post at each corner1 about #a ft4 in the ground4 ,take two poles about #g ft4 long1 and having procured two strong five-bushel corn sacks1 cut holes in the bottom corners1 put the poles through1 bringing the mouths of the sacks together1 and secure them there with a strong stitch or two4 ,put your poles on the upright forked sticks1 and you have a couch that even ,sancho ,panza would have envied4 ,it is as well to fix stretchers or cross stays between the posts at head and foot4 ,in malarial countries1 sleeping on the ground is distinctly dangerous1 and as such districts are usually thickly timbered1 the ,northern ,territory hammock is an admirable device1 more particularly where mosquitoes abound4 ,,northern ,,territory ,,hammock ,this hammock1 which is almost a standing bedplace when rigged1 is constructed as follows3--,to a piece of strong canvas #g feet long and #b #a_/b feet wide1 put a broad hem1 say #c #a_/b inches wide at each end4 ,into this hem run a rough stick1 about #b feet #h inches by #b inches diameter4 ,round the centre of the stick pass a piece of strong three-quarter inch rope1 #h to #aj feet long and knot it1 so as to leave a short end in which a metal eye is inserted4 ,to each end of the two sticks a piece of quarter-inch lashing1 about #f feet long1 is securely attached4 ,to make the mosquito covering take #ah feet of ordinary strong cheese cloth1 and two pieces of strong calico of the same size as the canvas bed2 put hems in the ends of the upper one large enough to take half-inch sticks1 to all four extremities of which #h feet of whipcord is to be attached4 ,the calico forms the top and bottom of what we used to call the meat safe1 the sides being of cheese cloth4 ,a small1 flapped opening is left on the lower side4 ,when once inside you are quite safe from mosquito bites4 ,to rig the above1 two trees are chosen #g to #h feet apart1 or two stayed poles can be erected if no trees are available4 ,the bed is rigged about #c feet from the ground by taking the rope round the trees or poles1 and pulling the canvas taut by means of the metal eyelet4 ,then the lashings at the extremities of the sticks are fixed about #c feet further up the trees and you have a bed something between a hammock and a standing bed4 ,the mosquito net is fixed above the hammock in a similar manner1 except that it does not require the centre stay4 ,an old friend of mine once had a rather startling experience which caused him to swear by the ,northern ,territory hammock4 ,he was camped near the banks of a muddy creek on the ,daly ,river1 and had fortunately hung his meat safe about four feet high4 ,the night was very dark1 and some hours after retiring he heard a crash among his tin camp utensils1 and the noise of some animal moving below him4 ,thinking his visitor was a stray dingo1 or wild dog1 he gave a yell to frighten the brute away1 and hearing it go1 he calmly went to sleep again4 ,had he known who his caller really was1 he would not have felt so comfortable4 ,in the morning on the damp ground below1 he found the tracks of a fourteen foot alligator1 which was also out prospecting1 but which1 fortunately1 had not thought of investigating the meat safe4 ,,purifying ,,water ,there is not a more fertile disease distributor1 particularly in a new country1 than water4 ,the uninitiated generally take it for granted that so long as water looks clear it is necessarily pure and wholesome2 as a matter of fact the contrary is more usually the case1 except in very well watered countries1 and such1 as a rule1 are not those in which gold is most plentifully got by the average prospector4 ,i have seen foolish fellows1 who were parched with a long tramp1 drink water in quantity in which living organisms could be seen with the naked eye1 without taking even the ordinary precaution of straining it through a piece of linen4 ,if they contracted hydatids1 typhoid fever1 or other ailments1 which thin our mining camps of the strong1 lusty1 careless youths1 who could wonder8 ,the best of all means of purifying water from organic substances is to boil it4 ,if it be very bad1 add carbon in the form of the charcoal from your camp fire4 ,if it be thick1 you may1 with advantage1 add a little of the ash also4 ,i once rode forty-five miles with nearly beaten horses to a native well1 or rock hole1 to find water1 the next stage being over fifty miles further4 ,the well was found1 but the water in it was very bad2 for in it was the body of a dead kangaroo which had apparently been there for weeks4 ,the wretched horses1 half frantic with thirst1 did manage to drink a few mouthfuls1 but we could not4 ,i filled our largest billycan1 holding about a gallon1 slung it over the fire and added1 as the wood burnt down1 charcoal1 till the top was covered to a depth of two inches4 ,with the charcoal there was1 of course1 a little ash containing bi-carbonate of potassium4 ,the effect was marvellous4 ,so soon as the horrible soup came to the boil1 the impurities coagulated1 and after keeping it at boiling temperature for about half an hour1 it was removed from the fire1 the cinders skimmed out1 and the water allowed to settle1 which it did very quickly4 ,it was then decanted off into an ordinary prospector's pan1 and some used to make tea 7the flavour of which can be better imagined than described72 the remainder was allowed to stand all night1 a few pieces of charcoal being added4 ,in the morning it was bright1 clear1 and absolutely sweet4 ,this experience is worth knowing as many a bad attack of typhoid and other fevers would be averted if practical precautions of this kind were only used4 ,,to ,,obtain ,,water ,,from ,,roots ,the greatest necessity of animal life is water4 ,there are1 however1 vast areas of the earth's surface where this most precious element is lamentably lacking1 and such1 unfortunately1 is the case in many rich auriferous districts4 ,to the practical man there are many indications of water4 ,these1 of course1 vary in different countries4 ,sometimes it is the herbage1 but probably1 the best of all is the presence of carnivorous animals and birds4 ,these are never found far from water4 ,in ,australia the not over-loved wily old crow is a pretty sure indicator of water within reasonable distance--water may be extracted from the roots of the ,mallee 7,eucalyptus dumosa and gracilis7--the ,box 7,eucalyptus hemiphloia7 and the ,water ,bush 7,hakea leucoptera74 ,to extract it the roots are dug up1 cut into lengths of about a foot1 and placed upright in a can2 the lower ends being a few inches above the bottom4 ,it is simply astonishing how much wholesome1 if at times somewhat astringent1 water may thus be obtained in a few hours1 particularly at night4 ,hakea leucoptera4 ,pins and needles4--,maiden1 in his work ,useful ,native ,plants of ,australia1 says3 ,in an experiment on a water-yielding ,hakea1 the first root1 about half an inch in diameter and six or eight feet long1 yielded quickly1 and in large drops about a wine-glass full of really excellent water4 ,this valuable1 though not particularly ornamental shrub 7for it never attains to the dimensions of a tree71 is found1 to the best of my belief1 in all parts of ,australia1 although it is said to be absent from ,west ,australia4 ,as to this ,i don't feel quite sure4 ,i have seen it from the centre of the sea as far west as ,streaky ,bay1 and believe ,i have seen it further ,west still4 ,considering the great similarity of much of the flora of ,south ,africa to that of ,australia1 it is probable that some species of the water-bearing ,hakea might be found there4 ,it can readily be recognised by its acicular1 needle-like leaves1 and more particularly by its peculiarly shaped seed vessel1 which resembles the pattern on an old-fashioned ,indian shawl4 ,if the water found is too impure for drinking purposes and the trouble arises from visible animalculae only1 straining through a pocket-handkerchief is better than nothing2 the carbon filter is better still2 but nothing is so effective as boiling4 ,a carbon filter is a tube with a wad of compressed carbon inserted1 through which the water is sucked1 but as a rule clay-coloured water is comparatively innocuous1 but beware of the bright1 limpid water of long stagnant rock water-holes4 ,,to ,,make ,,an ,,effective ,,filter ,take a nail-can1 keg1 cask1 or any other vessel1 or even an ordinary wooden case 7well tarred inside1 if possible1 to make it water-tight74 ,make a hole or several holes in the bottom1 and set it over a tank or bucket4 ,into the bottom of the filter put 7#a7 a few inches of washed broken stone2 7#b7 about four inches of charcoal2 7#c7 say three inches of clean coarse sand 7if not to hand you can manufacture it by crushing quartz with your pestle and mortar71 and 7#d7 alternate layers of charcoal and sand until the vessel is half filled4 ,fill the top half with water1 and renew from time to time1 and you have a filter which is as effective as the best ,london made article4 ,but it is better to boil your water whether you filter afterwards or not4 ,clear the inside of the water-cask frequently1 and occasionally add to the water a little ,condy's fluid1 as it destroys organic matter4 ,a useful cement for stopping leaky places in casks is made as follows3 ,tallow #be parts1 lard #dj parts1 sifted wood ash #be parts4 ,mix together by heating1 and apply with a knife blade which has just been heated4 ,,canvas ,,water ,,bags ,are easily made1 and are very handy for carrying small supplies of drinking-water when prospecting in a dry country2 they have the advantage of keeping the water cool in the hottest weather1 by reason on the evaporation4 ,the mouthpiece is made of the neck of a bottle securely sewn in4 ,,medicine ,,case ,medicine is also a matter well worthy of thought4 ,the author's worst enemy would not call him a mollycoddle1 yet he has never travelled in far wilds without carrying something in the way of medicine4 ,first1 then1 on this subject1 it cannot be too often reiterated that if common ,epsom salts were a guinea an ounce instead of a penny the medicine would be valued accordingly1 but it is somewhat bulky4 ,what ,i especially recommend1 however1 is a small pocket-case of the more commonly known homeopathic remedies1 ,mother tinctures1 which are small1 light1 and portable1 with a small simple book of instructions4 ,though generally an allopath in practice1 ,i once saved my own life1 and have certainly helped others by a little knowledge in diagnosing complaints and having simple homeopathic remedies at hand to be used in the first stages of what might otherwise have been serious illnesses4 ,,producing ,,fire ,every one has heard1 and most believe1 that fire may be easily produced by rubbing together two pieces of wood4 ,i have seen it done by natives1 but they seldom make use of the operation1 which is generally laborious1 preferring to carry lighted fire sticks for miles4 ,i have never succeeded in the experiment4 ,sometimes1 however1 it is almost a matter of life or death to be able to produce fire4 ,the back of a pocket knife1 or an old file with a fragment of flint1 quartz1 or pyrites struck smartly together over the remains of a burnt piece of calico1 will in deft hands produce a spark which can be fanned to a glow1 and so ignite other material1 till a fire is produced4 ,also it may not be generally known that he who carries a watch carries a burning glass with which he can1 in clear weather1 produce fire at will4 ,all that is required is to remove the glass of your watch and carefully three parts fill it with water 7salt or fresh74 ,this forms a lens which1 held steadily1 will easily ignite any light1 dry1 inflammable substance4 ,when firearms are carried1 cut a cartridge so that only about a quarter of the charge of powder remains4 ,damp some powder and rub it on a small piece of dry cotton cloth or well-rubbed brown paper4 ,push a loose pellet of this into the barrel1 insert your half cartridge1 fire at the ground1 when the wad will readily ignite1 and can be blown into flame4 ,,to ,,copy ,,correspondence ,the prospector is not usually a business man2 hence in dealing with business men who1 like ,hamlet1 are indifferent honest1 he frequently comes to grief through not having a copy of his correspondence4 ,it is most desirable1 therefore1 either to carry a carbon paper duplicating book and a stylus1 or by adding a little sugar to good ordinary black ink you may make a copying ink2 then with the aid of a yellow back octavo novel1 two pieces of board1 and some ordinary tissue paper1 you may take a copy of any letter you send4 ,,to ,,provide ,a ,,simple ,,telegraphic ,,code ,buy a couple of cheap small dictionaries of the same edition1 send one to your correspondent with an intimation that he is to read up or down so many words from the one indicated when receiving a message4 ,thus1 if ,i want to say ,claim is looking well1 ,i take a shilling dictionary1 send a copy to my correspondent with the intimation that the real word is seven down1 and telegraph--,civilian looking weird2 this1 if looked up in ,worcester's little pocket dictionary1 for instance1 will read ,claim looking well4 ,any dictionary will do1 so long as both parties have a copy and understand which is the right word4 ,by arrangement this plan can be varied from time to time if you have any idea that your code can be read by others4 ,a ,,serviceable ,,soap ,wood ashes from the camp fire are boiled from day to day in a small quantity of water1 and allowed to settle1 the clear liquid being decanted off4 ,when the required quantity of weak lye has been accumulated1 evaporate by boiling1 till a sufficient degree of strength has been obtained4 ,now melt down some mutton fat1 and1 while hot1 add to the boiling lye4 ,continue boiling and stirring till the mixture is about the consistency of thick porridge1 pour into any convenient flat vessel1 and let it stand till cool4 ,if you have any resin in store1 a little powdered and added gradually to the melting tallow1 before mixing with the lye1 will stiffen your soap4 ,,to ,,cross ,a ,,flooded ,,stream ,take a half-gallon1 or larger1 tin billy can1 enclose it in a strong cotton handkerchief or cotton cloth1 knotting same over the lid1 invert1 and1 taking the knot in the hand1 you have a floating appliance which will sustain you in any water1 whether you are a swimmer or not4 ,the high silk hat of civilisation would act as well as the can1 but these are not usually found far afield4 ,,to ,,make ,a ,,hide ,,bucket ,at times when prospecting in an incline or underlay shaft1 particularly where the walls of the lode are irregular1 a hide bucket will be found preferable to an iron one4 ,the mode of manufacture is as follows3 ,procure an ox hide1 green1 if possible2 if dry1 it should be soaked until quite soft4 ,cut some thin strips of hide for sewing or lacing4 ,now shape a bag or pocket of size sufficient to hold about a hundredweight of stone1 and by puncturing the edges with a knife1 marline-spike1 or other pointed tool1 sew together2 make a handle of twisted or pleated hide1 and having filled your bucket with dry sand or earth let it stand till the whole is quite dry1 when it will be properly distended and will maintain its shape until worn out4 ,,to ,,make ,a ,,slush ,,lamp ,where candles are scarce and kerosine is not1 a slush lamp is a useful substitute4 ,take an old but sound quart tin pannikin1 half fill it with sand or earth1 and prepare a thin stick of pine1 round which wrap a strip of soft cotton cloth4 ,the stick should be about half an inch longer than the depth of the pannikin4 ,melt some waste fat1 fill the pannikin therewith1 push the stick down into the earth at the bottom1 and you have a light1 which1 if not equal to the electric or incandescent gas burner1 is quite serviceable4 ,in ,australia the soft velvety core of the bottle brush1 ,banksia marginata1 is often used instead of the cotton wick4 ,,chapter ,,xii ,,rules ,,of ,,thumb ,,mining ,,appliances ,,and ,,methods ,a ,,temporary ,,forge ,what prospector has not at times been troubled for the want of a forge8 ,to steel or harden a pick or sharpen a drill is comparatively easy1 but there is often a difficulty in getting a forge4 ,big single action bellows are sometimes bought at great expense1 and some ingenious fellows have made an imitation of the blacksmith's bellows by means of sheepskins and rough boards4 ,with inadequate material and appliances to hand1 the following will be found easier to construct and more lasting when constructed4 ,only a single piece of iron is required1 and1 at a pinch1 one could even dispense with that by using a slab of talcose material1 roughly shaping a hearth therein and making a hole for the blast4 ,first1 construct a framing about the height of an ordinary smith's forge4 ,this can made with saplings and bark1 or better still1 if available1 out of an empty packing case about three feet square4 ,fill the frame or case with slightly damped earth and ram it tight1 leaving the usual hollow hearth4 ,then form a chamber below the perforated hearth opening to the rear4 ,now construct a centrifugal fan1 such as is used for the ventilation of shallow shafts and workings4 ,set this up behind the hearth and revolve by means of a wooden multiplying wheel4 ,a piece of ordinary washing line rope1 or sash line rope1 well resined if resin can be got--but pitch1 tar1 or wax will do by adding a little fine dust to prevent sticking--is used as a belt4 ,with very rough materials a handy man can thus make a forge that will answer ordinary requirements4--,n4,b4 ,do not use clay for your hearth bed unless you can get a highly aluminous clay1 and can give it full time to dry before the forge fire is lit4 ,ordinary surface soil1 not too sandy1 acts well1 if damped and rammed thoroughly4 ,of course1 if you can get an iron nozzle for your blower the whole operation is simplified4 ,,simple ,,way ,,of ,,making ,,charcoal ,dig a pit #e feet square by #c feet deep and fill with fuel4 ,after lighting1 see that the pit is kept full4 ,the hot embers will gradually sink to the bottom4 ,the fuel should be kept burning fiercely until the pit seems almost full1 when more fuel should be added1 raising the heap about a foot above the level of the ground4 ,the earth dug out of the pit should then be shovelled back over the burning mass4 ,after leaving it to cool for #bd hours the pit will be found nearly full of charcoal4 ,about one-quarter the weight of the dry fuel used should be recovered in charcoal4 ,,rough ,,smelting ,,on ,,the ,,mine ,rough smelting on the mine is effected with a flux of borax1 carbonate of soda1 or1 as ,i have often done1 with some powdered white glass4 ,when the gold is smelted and the flux has settled down quietly in a liquid state1 the bulk of the latter may be removed1 to facilitate pouring into the mould1 by dipping an iron rod alternately into the flux and then into a little water1 and knocking off the ball of congealed flux which adheres after each dip4 ,this flux should1 however1 be crushed with a pestle and mortar and panned off1 as1 in certain cases1 it may contain tiny globules of gold4 ,,misfires ,,in ,,blasting ,one of the most common sources of accident in mining operations is due either to carelessness or to the use of defective material in blasting4 ,a shot misses1 generally for one of two reasons2 either the explosive1 the cap1 or the fuse 7most often the latter71 is inferior or defective2 or the charging is incompletely performed4 ,sometimes the fuse is not placed properly in the detonator1 or the detonator is not properly enclosed in the cartridge1 or the fuse is injured by improper tamping4 ,if several shots have been fired together1 particularly at the change of a shift1 the men who have to remove the broken material may in so doing explode the missed charge4 ,or1 more inexcusable still1 men will often be so foolish as to try to clear out the drill hole and remove the missed cartridge4 ,when a charge is known to have missed all that is necessary to do in order to discharge it safely is to remove a few inches of tamping from the top of the drill hole1 place in the bore a plug of dynamite with cap and fuse attached1 put an inch or two of tamping over it and fire1 when the missed charge will also be exploded4 ,of course1 judgment must be used and the depth of the drill taken into consideration4 ,as a rule1 miners use far more tamping than is at all requisite4 ,the action of the charge will generally be found quite as effective with a few inches of covering matter as with a foot or more1 while the exploding of misfire cartridges is rendered simple1 as no removal of tamping is required before placing the top plug in case of misfire4 ,,to ,,prevent ,,loss ,,of ,,rich ,,specimens ,,in ,,blasting ,when blasting the cap of a lode1 particularly on rich shutes of gold1 the rock is apt to fly1 and rich specimens may be thrown far afield and so be lost4 ,a simple way of avoiding this is to procure a quantity of boughs1 which tie into loose bundles1 placing the leafy parts alternately end for end4 ,before firing1 pile these bundles over the blast and1 if care is used1 very few stones will fly4 ,the same device may be used in wide shallow shafts4 ,a ,,simple ,,mode ,,of ,,retorting ,,small ,,quantities ,,of ,,amalgam ,clean your amalgam and squeeze it as hard as possible through strong calico or chamois leather4 ,take a large sound potato1 cut off about a quarter from one end and scoop out a hole in the centre about twice as big as the ball of amalgam4 ,procure a piece of flat iron--an old spade will do as well as anything--insert the amalgam1 and1 having placed the potato1 cut side downwards1 thereon1 put the plate of iron on the forge1 heat up first gently1 then stronger1 till separation has taken place1 when the gold will be found in a bright clean button on the plate and the mercury in fine globules in the potato1 from which it can be re-collected by breaking up the partly or wholly cooked tuber under water in an enamelled or ordinary crockery basin4 ,,to ,,retort ,,small ,,quantities ,,of ,,mercury ,,for ,,amalgamating ,,assay ,,tests ,get two new tobacco pipes similar in shape1 with the biggest bowls and longest stems procurable4 ,break off the stem of one close to the bowl and fill the hole with well worked clay 7some battery slimes make the best luting clay74 ,set the stemless pipe on end in a clay bed1 and fill with amalgam1 pass a bit of thin iron or copper wire beneath it1 and bend the ends of the wire upwards4 ,now fit the whole pipe1 bowl inverted1 on to the under one1 luting the edges of both well with clay4 ,twist the wire over the top with a pair of nippers till the two bowls are fitted closely together1 and you have a retort that will stand any heat necessary to thoroughly distil mercury4 ,a ,,simple ,,mode ,,of ,,ascertaining ,,the ,,nominal ,,horse-,,power ,,of ,,an ,,engine ,multiply the internal diameter of the cylinder by itself and strike off the last figure of the quotient4 ,the diameter is #bj ,x #bj #bj #djj4 ,the ,h4,p4 is #dj4 ,the following rules will be found more professionally accurate from an engineering standpoint1 though the term horse-power is not now generally employed4 ,to find the ,nominal ,horse-power4--,for non-condensing engines3 ,multiply the square of the diameter of the cylinder in inches by #g and divide the product by #hj4 ,for condensing engines3 ,multiply the square of the diameter of the cylinder in inches by #g and divide the product by #bjj4 ,to find the ,actual ,horse-power of an engine1 multiply the area of the cylinder in square inches by the average effective pressure in pounds per square inch1 less #c lb4 per square inch as the frictional allowance1 and also by the speed of the piston in feet per minute1 dividing the product by #cc1jjj1 and the quotient will be the actual horse-power4 ,,scaling ,,copper ,,plates ,to scale copper plates they may be put over a charcoal or coke fire to slowly sublimate the quicksilver4 ,where possible1 the fireplace of a spare boiler can be utilised1 using a thin red fire4 ,after the entire evaporation of the quicksilver the plates should be slowly cooled1 rubbed with hydrochloric acid1 and put in a damp place overnight1 then rubbed with a solution of sal ammoniac and nitre in equal parts1 and again heated slowly over a red fire4 ,they must not be allowed to get red hot2 the proper degree of heat is indicated by the gold scale rising in blisters1 when the plates should be taken from the fire and the gold scraped off4 ,any part of the plate on which the gold has not blistered should be again rubbed with the solution and fired4 ,the gold scale should be collected in a glass or earthen dish and covered with nitric acid1 till all the copper is dissolved1 when the gold can be smelted in the usual way2 but after it is melted corrosive sublimate should be put in the crucible till a blue flame ceases to be given off4 ,a ,second ,method ,the simplest plan ,i know is to have a hole dug nine inches deep by about the size of the plate to be scaled2 place a brick at each corner1 and on each side1 halfway between1 get up a good fire2 let it burn down to strong embers1 or use charcoal1 then place the plate on three bars of iron extending between the three pairs of bricks1 have a strong solution of borax ready in which soak strips of old table blanket1 laying these over the plate and sprinkling them with the borax solution when the plate gets too hot4 ,after a time the deposit of mercury and gold on the plate will assume a white1 efflorescent appearance1 and may then be readily parted from the copper4 ,another ,method ,heat the plate over an open fire1 to drive off the mercury2 after which1 let it cool1 and saturate with dilute sulphuric acid for three hours1 or longer2 then sprinkle over the surface a mixture of equal parts of common salt and sal ammoniac1 and heat to redness2 then cool1 and the gold scale comes off freely2 the scale is then boiled in nitric or sulphuric acid1 to remove the copper1 previous to melting4 ,plates may be scaled about once in six months1 and will under ordinary circumstances produce about one ounce of clean gold for each superficial foot of copper surface employed4 ,i always paint the back of the plate with a mixture of boiled oil and turpentine1 or beeswax dissolved in turpentine1 to prevent the acid attacking the copper4 ,,how ,,to ,,supply ,,mercury ,,to ,,mortar ,,boxes ,i am indebted for the following to ,mr4 ,j4 ,m4 ,drake1 who1 speaking of his experience on the ,wentworth ,mine1 ,n4,s4,w41 says3 ,fully #ij per cent of the gold is saved on the outside plates1 only a small quantity remaining in the mortar4 ,the plates have a slope of #b in4 to #a ft4 ,no wells are used1 the amalgam traps saving any quicksilver which may leach off the plates4 ,the quicksilver is added every hour in the mortar4 ,the quantity is regulated by the mill manager in the following manner3 ,three pieces of wood1 #h in4 wide by #ab in4 long by #b in4 thick1 have #cb holes #a in4 deep bored in each of them4 ,these holes will just take a small #b oz4 phial4 ,the mill manager puts the required quantity of quicksilver in each bottle and the batteryman empties one bottle in each mortar every hour2 and puts it back in the hole upside down4 ,each block of wood lasts eight hours1 the duration of one man's shift4 ,this of course is for a #bj-;head mill with four mortars or boxes4 ,i commend this as an excellent mode of supplying the mercury to the boxes or mortars4 ,the quantity to be added depends on circumstances4 ,a careless battery attendant will often put in too much or too little when working without the automatic feeder4 ,i have known an attendant on suddenly awaking to the fact half through his shift1 that he had forgotten to put in any mercury1 to then empty into the stamper box two or three pounds weight2 with what effect may be easily surmised4 ,,how ,,water ,,should ,,enter ,,stamper ,,boxes ,the following extract which relates to ,californian ,gold ,mill practices is from ,bulletin ,no4 #f of the ,california ,state ,mining ,bureau4 ,i quite agree with the practice4 ,the battery water should enter both sides of the mortar in an even quantity1 and should be sufficient to keep a fairly thick pulp which will discharge freely through the grating or screen4 ,about #abj cubic feet of water per ton of crushed ore may be considered an average1 or #h to #aj cubic feet per stamp per hour4 ,screens of different materials and with different orifices are used2 the materials comprise wire cloth of brass or steel1 tough ,russian sheet iron1 ,english tinned plate1 and1 quite recently1 aluminium bronze4 ,the 'aluminium bronze' plates are much longer lived than either of the other kinds1 and have the further advantage that1 when worn out1 they can be sold for the value of the metal for remelting2 these plates are bought and sold by the pound1 and are said to contain #ie per cent of copper and #e per cent of aluminium4 ,steel screens are not so much used1 on account of their liability to rust4 ,i have had no experience with the aluminium bronze screen4 ,i presume1 however1 that it is used only for mills where mercury is not put in the mortars1 otherwise1 it would surely become amalgamated4 ,the same remark applies to brass wire cloth and tinned plate4 ,unless the metal of which they are composed will not readily amalgamate with mercury1 ,i should be chary of using new screen devices4 ,mercury is a most insidious metal and is often found most unexpectedly in places in the battery where it should not be4 ,probably aluminium steel would be better than any substance mentioned4 ,it would be hard1 light1 strong1 and not readily corrodible4 ,i am not aware if it has been tried4 ,under the heading of ,power for ,mills the following is taken from the same source4 ,,power ,,for ,,mills ,as the ,pelton wheel seems to find the most frequent application in ,california1 it may be convenient for millmen to have the following rule1 applicable to these wheels3 ,when the head of water is known in feet1 multiply it by #j4jjbdadg1 and the product is the horse-power obtainable from one miner's inch of water4 ,the power necessary for different mill parts is3 ,for each #hejlb4 stamp1 dropping #f in4 #ie times per minute1 #a4cc h4-p4 ,for each #gejlb4 stamp1 dropping #f in4 #ie times per minute1 #a4ah h4-p4 ,for each #fejlb4 stamp1 dropping #f in4 #ie times per minute1 #a4jj h4-p4 ,for an #h-;inch by #aj-;inch ,blake pattern rock-breaker #i4jj h4-p4 ,for a ,frue or ,triumph vanner1 with #bbj revolutions per min4 #j4ej h4-p4 ,for a #d-;feet clean-up pan1 making #cj revolutions per min4 #a4ej h4-p4 ,for an amalgamating barrel1 making #cj revolutions per min4 #b4ej h4-p4 ,for a mechanical batea1 making #cj revolutions per min4 #a4jj h4-p4 ,the writer has had small practical experience of the working of that excellent hydraulic motor1 the ,pelton wheel1 but if by horse-power in the table given is meant nominal horse-power1 it appears to be high4 ,working with #hjj cwt4 stamps1 #hj blows a minute1 one horse-power nominal will be found sufficient with any good modern engine1 which has no further burden than raising the stamps and pumping the feed water4 ,it is always well1 however1 particularly when providing engine power1 to err on the right side1 and make provision for more than is absolutely needed for actual battery requirements4 ,this rule applies with equal potency to pumping engines4 ,,to ,,avoid ,,loss ,,in ,,cleaning ,,up ,the following is a hint to quartz mill managers with respect to that common source of loss of gold involved in the almost inevitable loss of mercury in cleaning up operations4 ,i have known hundreds of pounds' worth of gold to be recovered from an old quartz mill site by the simple process of washing up the ground under the floor4 ,if you cannot afford to floor the whole of the battery with smooth concrete1 at all events smoothly concrete the floor of the cleaning-up room1 and let the floor slope towards the centre3 where a sink is provided4 ,any lost mercury must thus find its way to the centre1 where it will collect and can be panned off from time to time4 ,of course an underground drain and mercury trap must be provided4 ,,iron ,,extractor ,when using self-feeders1 fragments of steel tools are especially liable to get into the battery boxes or other crushing appliance where they sometimes cause great mischief4 ,i believe the following plan would be a practicable remedy for this evil4 ,by a belt from the cam or counter shaft1 cause a powerful electric magnet to extract all magnetic particles2 then1 by a simple ratchet movement1 at intervals withdraw the magnet and drop the adhering fragments into a receptacle by automatically switching off the electric current4 ,a powerful ordinary horseshoe magnet might probably do just as well1 but would require to be re-magnetised from time to time4 ,,to ,,silver ,,copper ,,plates ,to silver copper plates1 that is1 to amalgamate them on the face with mercury1 is really a most simple operation1 though many batterymen make a great mystery of it4 ,indeed1 when ,i first went into a quartz mill the process deemed necessary was not only a very tedious one1 but very dirty also4 ,to amalgamate with silver1 in fact1 to silver-plate your copper without resort to the electro-plating bath1 take any old silver 7failing that1 silver coin will do1 but is more expensive71 and dissolve it in somewhat dilute nitric acid1 using only just sufficient acid as will assist the process4 ,after some hours place the ball of amalgam in a piece of strong new calico and squeeze out any surplus mercury4 ,about an ounce of silver to the foot of copper is sufficient4 ,to apply it on new plates use nitric acid applied with a swab to free the surface of the copper from oxides or impurities1 then rub the ball of amalgam over the surface using some little force4 ,it is always well when coating copper plates with silver or zinc by means of mercury to let them stand dry for a day or two before using1 as the mercury oxidises and the coating metal more closely adheres4 ,only the very best copper plate procurable should be used for battery tables2 bad copper will always give trouble1 both in the first curing1 and after treatment4 ,it should not be heavily rolled copper1 as the more porous the metal the more easily will the mercury penetrate and amalgamate4 ,i cannot agree that any good is attained by scouring the plates with sand and alkalies1 as recommended in some books on the subject2 on the contrary1 ,i prefer the opposite mode of treatment1 and either face the plates with nitrate of silver and nitrate of mercury1 or else with sulphate of zinc and mercury1 in the form of what is called zinc amalgam4 ,if mine water1 which often contains a little free sulphuric acid1 is being used1 the latter plan is preferable4 ,the copper should be placed smoothly on the wooden table and secured firmly thereto by copper tacks4 ,if the plate should be bent or buckled1 it may be flattened by beating it with a heavy hammer1 taking care to interpose a piece of inch-thick soft wood between hammer and plate4 ,to coat with mercury only1 procure some nitrate of mercury4 ,this is easily made by placing mercury in an earthenware bowl1 pouring somewhat dilute nitric acid on it1 and letting it stand till the metallic mercury is changed to a white crystal4 ,dense reddish-brown fumes will arise1 which are injurious if breathed1 so the operation should be conducted either in the open air1 or where there is a draught4 ,having your silvering solution ready1 which is to be somewhat diluted with water1 next take two swabs1 with handles about #ab inches long1 dip the first into a basin containing dilute nitric acid1 and rub it rapidly over about a foot of the surface of the plate2 the oxide of copper will be absolutely removed1 and the surface of the copper rendered pure and bright2 then take the other swab1 wet with the dilute nitric of mercury1 and pass it over the clean surface1 rubbing it well in4 ,continue this till the whole plate has a coating of mercury4 ,it may be well to go over it more than once4 ,now turn on the water and wash the plate clean1 sprinkle with metallic mercury1 rubbing it upwards until the plate will hold no more4 ,a basin with nitrate of mercury may be kept handy1 and the plates touched up from time to time for a few days until they get amalgamated with gold1 after which1 unless you have much base metal to contend with1 they will give no further trouble4 ,it must be remembered1 however1 that an excessive use of nitric acid will result in waste of mercury1 which will be carried off in a milky stream with the water2 and also that it will cause the amalgam to become very hard1 and less active in attracting other particles of gold4 ,if you are treating the plate with nitrate of silver prepared as already mentioned1 clean the plate with dilute nitric acid1 rub the surface with the ball of amalgam1 following with the swab and fairly rubbing in4 ,it will be well to prepare the plate some days before requiring to use it1 as a better adhesion of the silver and copper takes place than if mercury is applied at once4 ,to amalgamate with zinc amalgam1 clean the copper plate by means of a swab1 with fairly strong sulphuric acid diluted with water2 then while wet apply the zinc-mercury mixture and well rub in4 ,to prepare the zinc-amalgam1 clip some zinc 7the lining of packing cases will do7 into small pieces and immerse them in mercury after washing them with a little weak sulphuric acid and water to remove any coating of oxide4 ,when the mercury will absorb no more zinc1 squeeze through chamois leather or calico 7as for silver amalgam71 and well rub in4 ,the plate thus prepared should stand for a few days1 dry1 before using4 ,if1 before amalgamation with gold takes place1 oxide of copper or other scum should rise on this plate a little very dilute sulphuric acid will instantly remove it4 ,sodium and cyanide of potassium are frequently used in dressing-plates1 but the former should be very sparingly employed1 as it will often do more harm than good by taking up all sorts of base metals with the amalgam1 and so presenting a surface which the gold will pass over without adhering to4 ,where water is scarce1 and is consequently used over and over again1 lime may be added to the pulp1 or1 if lime is not procurable1 wood ashes may be used4 ,the effect is two-fold2 the lime not only tends to sweeten sulphide ores and keep the tables clean1 but also causes the water to cleanse itself more quickly of the slimes1 which will be more rapidly precipitated4 ,when zinc amalgam is used1 alkalies would1 of course1 be detrimental4 ,when no other water than that from the mine is available1 difficulties often arise owing to the impurities it contains4 ,these are various1 but among the most common are the soluble sulphates1 and sometimes free sulphuric acid evolved by the oxidisation of metallic sulphides4 ,in the presence of this difficulty1 do one of two things2 either utilise or neutralise4 ,in certain cases1 ,i recommend the former4 ,sometime since ,i was treating1 for gold extraction1 material from a mine which was very complex in character1 and for which ,i coined the term polysynthetic4 ,this contained about half a dozen different sulphides4 ,the upper parts of the lode being partially oxidised1 free sulphuric acid 7,h#b,,so#d7 was evolved4 ,i therefore1 following out a former discovery1 added a little metallic zinc to the mercury in the boxes and on the plates with excellent results4 ,when the free acid in the ore began to give out in the lower levels ,i added minute quantities of sulphuric acid to the water from time to time4 ,i have since found1 however1 that with some water1 particularly ,west ,australian1 the reaction is so feeble 7probably owing to the lime and magnesia present7 as to make this mode of treatment unsuitable4 ,,how ,,to ,,make ,a ,,dolly ,i have seen some rather elaborate dollies1 intended to be worked with amalgamating tables1 but the usual prototype of the quartz mill is set up1 more or less1 as follows3 ,a tree stump1 from #i in4 to a foot diameter1 is levelled off smoothly at about #b ft4 from the ground2 on this is firmly fixed a circular plate of #a_/b in4 iron1 say #i in4 in diameter2 a band of #c_/af in4 iron1 about #h or #i in4 in height1 fits more or less closely round the plate4 ,this is the battery box4 ,a beam of heavy wood1 about #c in4 diameter and #f ft4 long1 shod with iron1 is vertically suspended1 about #i in4 above the stump1 from a flexible sapling with just sufficient spring in it to raise the pestle to the required height4 ,about #b ft4 from the bottom the hanging beam is pierced with an augur hole and a rounded piece of wood1 #a #a_/b in4 by #ah in41 is driven through to serve as a handle for the man who is to do the pounding4 ,his mate breaks the stone to about #b in4 gauge and feeds the box1 lifting the ring from time to time to sweep off the triturated gangue1 which he screens through a sieve into a pan and washes off1 either by means of a cradle or simply by panning4 ,in dollying it generally pays to burn the stone1 as so much labour in crushing is thus saved4 ,a couple of small kilns to hold about a ton each dug out of a clay bank will be found to save fuel where firewood is scarce1 and will more thoroughly burn the stone and dissipate the base metals1 but it must be remembered that gold from burnt stone is liable to become so encrusted with the base metal oxides as to be difficult to amalgamate4 ,,rough ,,windlass ,make two ,st4 ,andrew's crosses with four saplings1 the upper angle being shorter than the lower2 fix these upright1 one at each end of the shaft2 stay them together by cross pieces till you have constructed something like a horse1 such as is used for sawing wood1 the crutch being a little over #c feet high4 ,select a leg for a windlass barrel1 about #f in4 diameter and a foot longer than the distance between the supports1 as straight as is procurable2 cut in it two circular slots about an inch deep by #b in4 wide to fit into the forks2 at one end cut a straight slot #b in4 deep across the face4 ,now get a crooked bough1 as nearly the shape of a handle as nature has produced it1 and trim it into right angular shape1 fit one end into the barrel1 and you have a windlass that will pull up many a ton of stuff4 ,,puddler ,this is made by excavating a circular hole about #b ft4 #i in4 deep and1 say #ab ft4 in diameter4 ,an outer and inner wall are then constructed of slabs #b ft4 #f in4 in height to ground level1 the outer wall being thus #cj ft4 and the inner #ae ft4 in circumference4 ,the circular space between is floored with smooth hardwood slabs or boards1 and the whole made secure and water-tight4 ,in the middle of the inner enclosure a stout post is planted1 to stand a few inches above the wall1 and the surrounding space is filled up with clay rammed tight4 ,a strong iron pin is inserted in the centre of the post1 on which is fitted a revolving beam1 which hangs across the whole circumference of the machine and protrudes a couple of feet or so on each side4 ,to this beam are attached1 with short chains1 a couple of drags made like ,v-shaped harrows by driving a piece of red iron through a heavy frame1 shaped as a rectangular triangle4 ,to one end of the beam an old horse is attached1 who1 as he slowly walks round the circular track1 causes the harrows and drags to so puddle the washdirt and water in the great wooden enclosure that the clay is gradually disintegrated1 and flows off with the water which is from time to time admitted4 ,the clean gravel is then run through a cradle1 long ,tom1 or sluice1 and the gold saved4 ,this1 of course1 is the simplest form of gold mining4 ,in the great alluvial mines other and more intricate appliances are used but the principle of extraction is the same4 ,a ,,makeshift ,,pump ,to make a temporary small draw-lift pump1 which will work down to a hundred feet or more if required1 take a large size common suction ,douglas pump1 and1 after removing the top and handle1 fix the pump as close to the highest level of the water in the shaft as can be arranged4 ,now make a square water-tight wooden column of slightly greater capacity than the suction pipe1 fix this to the top of the pump1 and by means of wooden rods1 work the whole from the surface1 using either a longer levered handle or1 with a little ingenuity1 horse-power4 ,if you can get it the iron downpipe used to carry the water from the guttering of houses is more easily adapted for the pipe column2 then1 also1 iron pump rods can be used but ,i have raised water between #fj and #gj feet with a large size ,douglas pump provided only with a wooden column and rods4 ,,squeezing ,,amalgam ,for squeezing amalgam1 strong calico1 not too coarse1 previously soaked in clean water1 is quite as good as ordinary chamois leather4 ,some gold is fine enough to escape through either4 ,,mercury ,,extractor ,the mercury extractor or amalgam separator is a machine which is very simple in construction1 and is stated to be most efficient in extracting quicksilver from amalgam1 as it requires but from two to three minutes to extract the bulk of the mercury from one hundred pounds of amalgam1 leaving the amalgam drier than when strained in the ordinary way by squeezing through chamois leather or calico4 ,the principle is that of the ,de ,laval cream separator--i4e41 rapid centrifugal motion4 ,the appliance is easily put together1 and as easily taken apart4 ,the cylinder is made of steel1 and is run at a very high rate of speed4 ,the general construction of the appliance is as follows3 ,the casing or receiver is a steel cylinder1 which has a pivot at the bottom to receive the step for an upright hollow shaft1 to which a second cylinder of smaller diameter is attached4 ,the second cylinder is perforated1 and a fine wire cloth is inserted4 ,the mercury1 after passing through the cloth1 is discharged through the perforations4 ,when the machine is revolved at great speed1 the mercury is forced into the outside cylinder1 leaving the amalgam1 which has been first placed in a calico or canvas bag1 in a much drier state than it could be strained by hand4 ,while not prepared to endorse absolutely all that is claimed for this appliance1 ,i consider that it has mechanical probability on its side1 and that where large quantities of amalgam have to be treated it will be found useful and effective4 ,,sluice ,,plates ,i am indebted to ,mr4 ,f4 ,w4 ,drake for the following account of sluice plates1 which ,i have never tried1 but think the device worth attention3 ,an addition has been made to the gold-saving appliances by the placing of what are called in ,america1 'sluice plates' below the ordinary table4 ,the pulp now flows over an amalgamating surface1 #ad ft4 long by #d ft4 wide1 sloping #a #a_/b in4 to the foot1 and is then contracted into a copper-plated sluice #ae ft4 long by #ad in4 wide1 having a fall of #a in4 to the foot4 ,our mill manager 7,mr4 ,g4 ,c4 ,knapp7 advocated these sluice plates for a long time before ,i would consent to a trial4 ,i contended that as we got little or no amalgam from the lower end of our table plates there was no gold going away capable of being recovered by copper plates2 and even if it were1 narrow sluice plates were a step in the wrong direction4 ,if anything the amalgamating surface should be widened to give the particles of gold a better chance to settle4 ,his argument was that the conditions should be changed2 by narrowing the stream and giving it less fall1 gold1 which was incapable of amalgamation on the wide plates1 would be saved4 ,we finally put one in1 and it proved so successful that we now have one at the end of each table4 ,the per-centage recovered on the sluice plates1 of the total yield1 varies1 and has been as follows3--,october1 #i4a per cent2 ,november1 #f4i per cent2 ,december1 #f4d per cent2 ,january1 #d4c per cent2 ,february1 #i4c per cent4 ,,measuring ,,inaccessible ,,distances ,to ascertain the width of a difficult gorge1 a deep river1 or treacherous swamp without crossing and measuring1 sight a conspicuous object at the edge of the bank on the farther side2 then as nearly opposite and square as possible plant a stake about five feet high1 walk along the nearer margin to what you guess to be half the distance across 7exactitude in this respect is not material to the result71 there plant another stake1 and continuing in a straight line put in a third4 ,the stakes must be equal distances apart and as nearly as possible at a right angle to the first line4 ,now1 carrying in hand a fourth stake1 strike a line inland at right angles to the base and as soon as sighting over the fourth stake1 you can get the fourth and second stakes and the object on the opposite shore in line your problem is complete4 ,the distance between ,no4 #d and ,no4 #c stakes is the same as that between ,no4 #a and the opposite bank4 ,,to ,,set ,,out ,a ,,right ,,angle ,,with ,a ,,tape ,measure #dj ft4 on the line to which you wish to run at right angles1 and put pegs at ,a and ,b2 then1 with the end of the tape held carefully at ,a1 take #hj ft41 and have the #hj ft4 mark held at ,b4 ,take the #ej ft4 mark and pull from ,a and ,b until the tape lies straight and even1 you will then have the point ,c perpendicular to ,,ab4 ,continue straight lines by sighting over two sticks in the well-known way4 ,another method4--,stick a pin in each corner of a square board1 and look diagonally across them1 first in the direction of the line to which you wish to run at right angles1 and then for the new line sight across the other two pins4 ,a ,,simple ,,levelling ,,instrument ,fasten a common carpenter's square in a slit to the top of a stake by means of a screw1 and then tie a plumb-line at the angle so that it may hang along the short arm1 when the plumb-line hangs vertically and sights may be taken over it4 ,a carpenter's spirit-level set on an adjustable stand will do as well4 ,the other arm will then be a level4 ,another very simple1 but effective1 device for finding a level line is by means of a triangle of wood made of half-inch boards from #i to #ab ft4 long4 ,to make the legs level1 set the triangle up on fairly level ground1 suspend a plummet from the top and mark on the cross-piece where the line touches it4 ,then reverse the triangle1 end for end1 exactly1 and mark the new line the plumb-line makes4 ,now make a new mark exactly half way between the two1 and when the plumb-line coincides with this1 the two legs are standing on level ground4 ,for short water races this is a very handy method of laying out a level line4 ,,to ,,measure ,,the ,,height ,,of ,a ,,standing ,,tree ,take a stake about your own height1 and walking from the butt of the tree to what you judge to be the height of the timber portion you want1 drive your stake into the ground till the top is level with your eyes2 now lie straight out on your back1 placing your feet against the stake1 and sight a point on the tree4 ,,ab equals ,,bc4 ,if ,,bc is1 say #dj ft41 that will be the height of your stick of timber4 ,thus1 much labour may be saved in felling trees the timber portion of which may afterwards be found to be too short for your purpose4 ,,levelling ,,by ,,aneroid ,,barometer ,this should be used more for ascertaining relatively large differences in altitudes than for purposes where any great nicety is required4 ,for hills under #bjjj ft41 the following rule will give a very close approximation1 and is easily remembered1 because #ee degrees1 the assumed temperature1 agrees with #ee degrees1 the significant figures in the #ee1jjj factor1 while the fractional correction contains two fours4 ,observe the altitudes and also the temperatures on the ,fahrenheit thermometer at top and bottom respectively1 of the hill1 and take the mean between them4 ,let ,b represent the mean altitude and b the mean temperature4 ,then #eejjj ,x ,b - b_/,b b height of the hill in feet for the temperature of #ee degrees4 ,add #a_/ddj of this result for every degree the mean temperature exceeds #ee degrees2 or subtract as much for every degree below #ee degrees4 ,,to ,,determine ,,heights ,,of ,,objects ,by ,shadows ,set up vertically a stick of known length1 and measure the length of its shadow upon a horizontal or other plane2 measure also the length of the shadow thrown by the object whose height is required4 ,then it will be3--,as the length of the stick's shadow is to the length of the stick itself1 so is the length of the shadow of the object to the object's height4 ,by ,reflection ,place a vessel of water upon the ground and recede from it until you see the top of the object reflected from the surface of the water4 ,then it will be3--,as your horizontal distance from the point of reflection is to the height of your eye above the reflecting surface1 so is the horizontal distance of the foot of the object from the vessel to its altitude above the said surface4 ,instrumentally ,read the vertical angle1 and multiply its natural tangent by the distance between instrument and foot of object2 the result is the height4 ,when much accuracy is not required vertical angles can be measured by means of a quadrant of simple construction4 ,the arc ,,ab is a quadrant1 graduated in degrees from ,b to ,a2 ,c1 the point from which the plummet ,p is suspended1 being the centre of the quadrant4 ,when the sights ,,ac are directed towards any object1 ,s1 the degrees in the arc1 ,,bp1 are the measure of the angle of elevation1 ,,sad1 of the object4 ,,to ,,find ,,the ,,depth ,,of ,a ,,shaft ,rule3--,square the number of seconds a stone takes to reach the bottom and multiply by #af4 ,thus1 if a stone takes #e seconds to fall to the bottom of a shaft-- #e squared #be2 and #be ,x #af #djj feet1 the required depth of shaft4 ,,description ,,of ,,plan ,,for ,,re-,,using ,,water ,where water is scarce it may be necessary to use it repeatedly4 ,in a case of this kind in ,egypt1 the ,arab miners have adopted an ingenious method which may be adapted to almost any set of conditions4 ,at a is a sump or water-pit2 b is an inclined plane on which the mineral is washed and whence the water escapes into a tank c2 d is a conduit for taking the water back to a2 e is a conduit or lever pump for raising the water4 ,a certain amount of filtration could easily be managed during the passage from c to a4 ,,cooling ,,compound ,,for ,,heated ,,bearings ,mercurial ointment mixed with black cylinder oil and applied every quarter of an hour1 or as often as expedient4 ,the following is also recommended as a good cooling compound for heavy bearings3--,tallow #b lb41 plumbage #f oz41 sugar of lead #d oz4 ,melt the tallow with gentle heat and add the other ingredients1 stirring until cold4 ,,cleaning ,,greasy ,,plummer ,,blocks ,when1 through carelessness or unpreventable cause1 plummer blocks and other detachable portions of machinery become clogged with sticky deposits of grease and impurities1 a simple mode of cleansing the same is to take about #ajjj parts by weight of boiling water1 to which add about #aj or #ae parts of ordinary washing soda4 ,keep the water on the boil and place therein the portions of the machine that are to be cleaned2 this treatment has the effect of quickly loosening all grease1 oil1 and dirt1 after which the metal is thoroughly washed and dried4 ,the action of the lye is to form with the grease a soap soluble in water4 ,to prevent lubricating oil hardening upon the parts of the machinery when in use1 add a third part of kerosene4 ,,an ,,excellent ,,anti-,,friction ,,compound ,for use on cams and stamper shanks1 which will be harmless should it drop into the mortar or stamper boxes1 is graphite 7black-lead7 and soft soap4 ,when the guides are wooden1 the soft soap need not be added2 black-lead made into a paste with water will act admirably4 ,,to ,,clean ,,brass ,oxalic acid #a oz41 rotten stone #f oz41 powdered gum arabic #a_/b oz41 sweet oil #a oz4 ,rub on with a piece of rag4 ,a ,,solvent ,,for ,,rust ,it is often very difficult1 and sometimes impossible1 to remove rust from articles made of iron4 ,those which are very thickly coated are most easily cleaned by being immersed in a nearly saturated solution of chloride of tin4 ,the length of time they remain in this bath is determined by the thickness of the coating of rust4 ,generally from twelve to twenty-four hours is long enough4 ,,to ,,protect ,,iron ,,and ,,steel ,,from ,,rust ,the following method is but little known1 although it deserves preference over many others4 ,add #g oz4 of quicklime to #a #c_/d pints of cold water4 ,let the mixture stand until the supernatant fluid is entirely clear4 ,then pour this off1 and mix with it enough olive oil to form a thick cream1 or rather to the consistency of melted and re-congealed butter4 ,grease the articles of iron or steel with this compound1 and then wrap them up in paper1 or if this cannot be done1 apply the mixture somewhat more thickly4 ,,to ,,keep ,,machinery ,,from ,,rusting ,take #a oz4 of camphor1 dissolve it in #a lb4 of melted lard2 mix with it 7after removing the scum7 as much fine black-lead as will give it an iron colour2 clean the machinery1 and smear it with this mixture4 ,after twenty-four hours rub off and clean with soft1 linen cloth4 ,this mixture will keep machinery clean for months under ordinary circumstances4 ,,fire-,,lute ,an excellent fire-lute is made of eight parts sharp sand1 two parts good clay1 and one part horse-dung2 mix and temper like mortar4 ,,rope-,,splicing ,a short splice is made by unlaying the ends of two pieces of rope to a sufficient length1 then interlaying them1 draw them close and push the strands of one under the strands of the other several times4 ,this splice makes a thick lump on the rope and is only used for slings1 block-straps1 cables1 etc4