,illustration ,,scientific ,,american ,,supplement ,,no4 #fja ,,new ,,york1 ,,july #i1 #ahhg ,scientific ,american ,supplement4 ,vol4 ,,xxiv1 ,no4 #fja4 ,scientific ,american established #ahde ,scientific ,american ,supplement1 #e a year4 ,scientific ,american and ,supplement1 #g a year4 99 99 99 99 99 ,,table ,,of ,,contents4 ,i4 ,,astronomy4--,a ,star ,finder4--,a simple apparatus that can be constructed by any mechanic4--#a illustration4 ,photographic ,study of ,stellar ,spectra1 ,harvard ,college ,observatory4 --,first annual report of the ,henry ,draper memorial observations4 --,review of the work by ,prof4 ,,edward ,c4 ,,pickering4 ,,ii4 ,,biology4--,sponges4--,the growth and life history of sponges4--,report of a recent lecture at the ,london ,royal ,institution by ,dr4 ,r4 ,,von ,,ledenfeld4 ,,iii4 ,,electricity4--,phenomena of ,alternating ,currents4--,by ,prof4 ,,elihu ,,thomson4--#af illustrations4 ,,iv4 ,,engineering4--,an ,english ,car ,coupling4--,description of an ,english automatic coupling4--#b illustrations4 ,a ,new ,process of ,casting ,iron and other ,metals upon ,lace1 ,embroideries1 ,fern ,leaves1 and other ,combustible ,materials4 --,by ,a4,e4 ,,outerbridge1 ,,jr4--,a new and eminently practical process of producing ornamental castings4--#d illustrations4 ,bricks and ,brick ,work4--,by ,prof4 ,t4 ,,roger ,,smith1 ,f4,r4,i4,b4,a4 --,the history and technical review of this subject4--,a most remarkable contribution to the engineering of architecture4 ,link ,belting4--,by ,,charles ,a4 ,,schieren4--,an interesting and practical paper on leather belting made of links4 --#i illustrations4 ,recent ,progress in ,gas ,engineering4--,a lecture by ,mr4 ,a4 ,,macpherson1 of ,kirkcaldy1 reviewing the last improvements in this branch4 ,v4 ,,miscellaneous4--,herbet's ,tepid ,douche4--,apparatus in use for bathing soldiers in the ,french barracks4--#a illustration4 ,kent's ,torsion ,balance4--,a new type of balance1 involving torsional suspension instead of knife edges4--#e illustrations4 ,preservative ,liquid4--,note on preservation of organic substances4 ,the ,falls of ,gairsoppa4--,the great ,indian falls1 higher than ,niagara4--#b illustrations4 ,the ,new ,british ,coinage and ,jubilee ,medal4--,illustrations and descriptions of the new pieces4--#h illustrations4 ,the ,winner of the ,derby4--,portrait and description of ,merry ,hampton4 ,,vi4 ,,naval ,,engineering4--,the ,falke ,type ,torpedo ,boat4--,the fastest type of ,british torpedo boat1 constructed by ,messrs4 ,yarrow ,co4--#a illustration4 ,the ,german ,navy4--,the ,new ,gunboat ,eber4--,a description of a late accession to the ,german navy4--#a illustration4 ,,vii4 ,,ordnance ,,and ,,gunnery4--,magazine ,rifles4--,continuation of this important article1 including the ,chaffee-,reece1 ,kropatschek1 and other magazine guns4--#c illustrations4 ,new ,british ,torpedo ,experiments4--,experiments with torpedoes against a ship4--,the efficiency or torpedo nets4--,the effects of ,whitehead torpedoes4 99 99 99 99 99 ,,the ,,falke ,,type ,,torpedo ,,boat4 ,among the different classes of vessels designed for special services1 constructed by ,messrs4 ,yarrow ,co41 at ,poplar1 for the ,british government1 is one which is stated to be the fastest torpedo boat in her majesty's navy4 ,this boat has been put through its official trials2 with a load of #ae tons1 running continuously for two hours without stopping1 a speed of #bc knots1 which is equal to #bf statute miles1 an hour was obtained4 ,the boat is #ace ft4 long by #ad ft4 beam4 ,its design is known as the ,falke type1 being in many respects similar1 but very superior1 to a torpedo boat of that name which was built two years ago by the same firm for the ,austrian government4 ,the form of the hull is of such a character as to give exceptional steering capabilities2 at the time of trial it was found to be able to steer round in a circle of a diameter of #ajj yards1 averaging #fb seconds4 ,the forward part of the boat is completely covered over by a large turtle back1 which is the customary form of the boats built by ,messrs4 ,yarrow ,co4 ,it was first introduced in the ,batoum1 which they constructed eight years ago for the ,russian government4 ,this turtle back increases the seaworthiness of the craft by throwing the water that comes upon it freely away4 ,it forms1 also1 good and roomy accommodation for the crew1 and incloses a large portion of the torpedo apparatus4 ,the forward torpedo gear consists of one torpedo gun1 adapted for ejecting the ,whitehead torpedo by means of gunpowder1 now preferred on account of its simplicity4 ,the boiler1 one of ,messrs4 ,yarrow ,co4's special construction1 of a type which has undergone many years of constant trial1 is capable of developing #a1ffj horse power4 ,in the engine room there are six engines--one for driving the boat1 two for compressing the air for the torpedoes1 an engine for working the dynamo for producing the electric light1 an engine for forcing air into the stoke-hole1 and an engine working in conjunction with the distilling apparatus for supplying drinking water for the crew and the waste incidental to the boiler4 ,aft of the engine room come the officers' quarters4 ,the stern of the boat is fitted up as a pantry and for the stowage of ammunition and stores4 ,on the deck are mounted three machine guns1 and near the stern an additional conning tower for use in case of need1 around which revolve two torpedo guns for firing the torpedoes off either side4 ,these torpedo guns can be trained to any angle it may be desired to fire them at4 ,on both conning towers are machine guns4--,illustrated ,london ,news4 ,illustration3 ,,the ,,falke ,,type ,,torpedo ,,boat1 ,,and ,,section ,,showing ,,general ,,arrangement4 99 99 99 99 99 ,,the ,,german ,,navy--,,the ,,new ,,gunboat ,,eber4 ,the gunboat ,eber is an improved vessel of the ,wolf type1 but differs from other vessels of its class in that it has not a complete iron hull1 only the frame and deck beams being of iron1 while the planking is of wood and yellow metal4 ,no copper is used on the bottom4 ,the composite system of building is looked upon with favor for ships of this kind1 because iron vessels which are kept permanently at stations in the tropics soon become overgrown in spite of good care1 and thus suffer a great loss of speed4 ,in a wooden vessel the crew's quarters are better and more healthful than in iron vessels1 for they are not as much affected by the temperature outside of the ship4 ,the greatest length of the ,eber is about #bde ft42 its breadth1 #bf ft42 its depth1 #ad ft42 and it has a displacement of about #ejj tons4 ,the armament will consist of three long #e in4 guns in center pivot carriages1 and a small number of revolvers4 ,one of the former will be placed at the stern on the quarter deck1 and the two others on the forecastle4 ,some of the revolvers will be on the quarter deck and some on the forecastle1 care being taken to arrange the guns so as to obtain the widest possible range1 thus enabling the ship to protect itself perfectly4 ,illustration3 ,,the ,,new ,,german ,,gunboat ,,eber4 ,the ,eber is provided with a two-cylinder1 compound engine1 which can generate #fej horse power1 giving the vessel a speed of #aa knots4 ,the coal bunkers are so large that the ship can travel #c1jjj miles at a speed slightly less than that just mentioned without requiring a fresh supply of coal4 ,the rigging is the same as in iron vessels of the ,wolf class1 and the sails are sufficiently large to allow the vessel to proceed without steam4 ,the ship will carry about #ij men1 including officers1 crew1 engineers1 and firemen4 ,a sum of #ade1jjj was appropriated for the construction and equipment of the ,eber1 which was begun at ,kiel in the latter part of #ahhe1 and was launched ,february #ae1 #ahhg4--;,illustrirte ,zeitung4 99 99 99 99 99 ,,new ,,british ,,torpedo ,,experiments4 ,the torpedo experiments against the ,resistance1 which have been suspended since ,november last1 were resumed on ,june #i at ,portsmouth by the officers of the ,vernon4 ,the injuries received by the ironclad in the previous experiments having been repaired1 so as to make the vessel watertight1 the old ship was towed up the harbor1 and moored in ,fareham ,creek4 ,our readers are aware that the ,resistance is an obsolete ironclad which has finished her career as a battle ship1 and that nothing could have converted her into a modern armorclad4 ,although it was intended to render the experiments final and conclusive as a practical demonstration under service conditions of the destructive effects of the ,whitehead torpedo when directed against a modern vessel of war1 the results still leave behind them much uncertainty4 ,the ,resistance was built of iron1 whereas battle ships are now exclusively constructed of steel1 and it would be perhaps hazardous to state that the behavior of the two metals under a sudden and violent shock would be exactly the same4 ,the construction of the double bottom of the old ship is also different4 ,since the last experiments were carried out against her1 however1 measures have been taken to make her as far as possible the counterpart1 so far as under water arrangements and coal protection are concerned1 of a modern ship of war4 ,at the last attack1 the ,whitehead was directed against the after part of the hull on the port side in wake of the boilers4 ,during the present series of experiments the old ship was assailed on the same side1 but directly amidships1 in the neighborhood of the engine room4 ,as no steam was got up in the boilers1 the effect of the jar upon the steam pipes1 glands1 and feed connections remains a matter of speculation4 ,so far as the consequences of the burst upon the structure of the hull itself is concerned1 every care was taken to make the ordeal as complete and instructive as possible4 ,the wing passage1 which has a maximum diameter of #c ft4 diminishing to a point1 was left empty1 although at the former experiments the lower portions were filled with coal4 ,but behind this1 and at a distance of #h ft4 from the bulkhead1 a longitudinal or fore and aft steel bulkhead #c_/h in4 thick had been worked to a length of #fa ft41 and1 with the coal with which the intervening compartment was packed1 formed 7as in recent armorclads7 a solid rampart1 #bj ft4 high1 for the defense of the engine room4 ,the height of the double bottom between the outer and inner skin plating is #b ft4 ,the watertight compartments were divided into stations by means of vertical lightening plates pierced by three holes1 and in order to make them1 as far as was practicable1 resemble the bracket frames of a modern armorclad1 the center of the plates was cut away so as to leave a single oval hole instead of the three circular holes4 ,in view of the differences of opinion which exist on the part of experts on the subject of under water protection1 the officers of the ,vernon had determined to submit the problem to the test of experiment4 ,for this purpose steel armor #a in4 thick had been worked along the outside of the upper skin of the double bottom throughout one of the compartments1 in addition to the other protection mentioned4 ,the ,resistance had been brought down by iron ballast to a trim of #be feet #i in4 aft and #ai ft4 #g in4 forward1 giving a mean draught of #bb feet #h inches4 ,she was consequently rather further down by the stern than before1 but was in other respects the same4 ,when in commission1 the ,resistance had a mean draught of #bf feet #aj inches4 ,the present series of experiments was of even greater importance than the first series4 ,the attack was gradually developed by means of fixed and outrigger charges of increasing power1 and the coup de grace was not given by means of a service ,whitehead in actual contact until various lessons had been derived4 ,the opening experiment on ,june #i consisted of an attack directed against a new system of torpedo defenses which are to be carried by ships in action1 or when in expectation of an attack1 rather than an assault upon the ship herself4 ,the previous experiments had clearly demonstrated that a ,whitehead1 when projected against a vessel at close range1 and consequently with a maximum of motive force1 could not get through the ordinary wire netting before expending its explosive energy in the air1 and that the spars by which the nets are boomed out from the ship's side could be reduced to #be ft4 in length without danger to the hull4 ,the ordinary wooden booms employed on board ship1 however1 are heavy and unwieldy1 weighing1 as they do1 more than half a ton each4 ,in ordinary circumstances1 the spars cannot be lowered into place and the nets made taut in less than a couple of hours1 and the work of stowing them is equally slow and laborious4 ,mr4 ,bullivant1 who manufactures the torpedo netting and hawsers for the navy1 has devised a method of getting rid of the difficulties complained of by substituting steel booms for the wooden booms and an arrangement of pulleys and runners1 whereby the protection can be run out and in1 topped and brailed up out of the way1 with great facility4 ,the system was tried at ,portsmouth last year with considerable success upon the ,dido1 but as it was thought that some of the fittings were somewhat frail and might collapse beneath the shock of a live torpedo1 it was resolved to submit them to a practical test under service conditions upon the ,resistance4 ,the ship was consequently fitted with three of the steel booms on the port side4 ,they were #cb ft4 long and spaced #de ft4 apart1 and connected by a jackstay to which the nets were attached4 ,each steel boom weighed #e cwt41 or less than half the weight of the ordinary boom1 and whereas the latter is fixed to the ship's side by a hook which is liable to be disconnected or broken by the jerk of an exploding torpedo1 ,mr4 ,bullivant's boom works in a universal or socket joint1 which cannot get out of gear except by fracture1 and which permits the boom to be moved in any direction1 whether vertically or fore and aft1 close in against the sides4 ,below each boom is a flange1 which serves as a line along which a traveler moves1 the latter being actuated by means of a topping line running over a pulley at the head and another near the heel4 ,upon the booms being topped to a perpendicular position1 the nets are attached to the runners at the bottom of the booms close inboard 7instead of1 under the existing system1 to the tops of the booms from boats alongside or otherwise71 and when this is done1 the mere depression of the booms into position will cause the nets to run out of their own accord4 ,in like manner1 when the occasion for their use has passed1 the raising of the boom will cause the nets to come alongside1 when they can either be brailed up through the grummets or disconnected for future use4 ,the action of the gear is so simple and rapid that the torpedo protection can be always ready without arresting the way of the ship4 ,as a length of net #cj ft4 by #bj ft4 deep weighs about #c cwt41 it will also be seen that the reduction of strains by working the crinolines from the heel instead of the head of the booms is considerable4 ,the attack by the ,whitehead upon the booms and nettings was made shortly before #b p4m41 at the time of high tide4 ,the whole affair occupied a very few minutes4 ,as soon as the red pennant was struck on board to show that ,mr4 ,bullivant was satisfied with the arrangements1 and that the target was ready1 the torpedo vessel ,vesuvius got under way1 and after circling round the doomed hulk discharged a ,whitehead against the netting from her under-water bow torpedo tube at an approximate range of #ej yards4 ,as on former occasions1 the missile was one of the old #af inch pattern1 but it was understood that the charge of gun cotton had been reduced to #hg lb41 so that the net protection should not bear a greater strain than would be the case in actual hostilities4 ,the torpedo1 which was set to a depth of about #aj feet1 struck the net in the middle and threw up an immense spout of water1 but without getting to the ship1 which was apparently uninjured4 ,although it hit the net immediately below the center boom1 no fracture occurred1 and the points remained intact4 ,although at the short range the torpedo would spin through the water at from #cj to #dj horse power1 and would deliver a formidable blow upon the net1 the thrust was effectually resisted1 though as a matter of course the net was much torn by the explosion of the baffled projectile4 ,although at the second torpedo attack made on the ,resistance1 the following day1 the offensive power that was brought to bear was quite exceptional1 the victory remained with the ship4 ,the charge exploded was an exceptionally heavy one4 ,it consisted of #bbj lb4 of gun cotton4 ,it was consequently more destructive than any which is ever likely to be launched against an armorclad much better prepared to resist it than the obsolete and time-worn ,resistance4 ,an idea1 however1 had got abroad that the ,russians either have or intend to have a locomotive torpedo capable of carrying the same weight of explosive in its head1 and the object of the experiment was to ascertain what would be the effect of the detonation of such an enormous charge upon the submerged portions of a ship of war4 ,but1 while this was no doubt the primary purpose in view1 the experiment also served the secondary purpose of determining the result of the explosion upon the net defenses of a ship4 ,mr4 ,bullivant's booms and runners1 which were found to be scarcely anything the worse from the ordeal of the previous day1 were again used4 ,the damaged net was taken away and one of the old service grummet nets slung in its place1 the cylinders containing the gun cotton being attached to the jackstay immediately in front of the battered sides1 and #cj feet from the hulk1 and sunk to a distance of #bj feet below the water line1 which would bring it about opposite the bend of the bilge4 ,by #c p4m4 everything was ready for the explosion of the charge--everybody had cleared out of the ship while the surrounding small craft drew off to a distance of #cjj feet4 ,the charge was electrically fired from a pinnace4 ,the burst was terrific and the reverberation was heard and the shock distinctly felt in the dockyard4 ,but the remarkable thing was that the hulk did not appear to jump in the least1 though there was not more than six feet of water under her keel4 ,that she would not be seriously crippled by the discharge seems to have been accepted as a foregone conclusion by ,captain ,long and the other torpedoists1 as the day for the third experiment had been fixed in advance2 but that the steel booms with their double flange running ways1 stays1 travelers1 and hinges should have resisted the tremendous jar and upheaval was a genuine surprise for all concerned1 and goes far to prove that except a vessel be taken unawares1 it will be impossible for a torpedo to come into actual contact with it4 ,at the experiments last year the wooden booms were unhinged and splintered under a much less violent shock4 ,but the steel booms employed1 though somewhat bent1 remained unbroken and in position1 and the joints were quite uninjured4 ,all that is necessary for perfect defense is that the booms should be made a little heavier4 ,the torpedo experiments against the ,resistance were resumed on ,june #ac1 when the old ironclad suffered some rough treatment4 ,as the experiment was understood to be the last of the second series1 and was fully expected to have a sensational termination1 a considerable number of interested spectators were attracted to the scene in ,fareham ,creek4 ,the torpedoists resorted to severe measures1 but with a distinctly useful purpose in view1 having bound the ship hand and foot1 so to speak1 in such a way that her name became a solecism4 ,they exploded #ie lb4 of gun cotton #bj ft4 below the water1 and in contact with her double bottom4 ,this amount of explosive represents the full charge of the old pattern #af in4 ,whiteheads2 but as the hulk was1 for prudential reasons1 moored close to a mud bank1 and as the water was consequently much too shallow to allow of a locomotive torpedo being set to run at the required depth1 a fixed charge was lashed fore and aft against the bottom plating of the ship and electrically exploded from ,no4 #ie torpedo boat4 ,in previous experiments this year the ironclad was attacked on the port side1 which had been specially strengthened for the occasion1 and the result was a victory for the defense4 ,on ,june #ac the starboard side was selected for attack1 in order that a comparison might be instituted with the effects produced under different conditions by a similar experiment4 ,last year in the latter case the double bottom was filled with coal2 and after the charge1 which was lashed against the ship in the same way1 had been exploded1 it was found that the bilge keel had been shivered for a length of #bj ft41 while the lower plating had been much bulged above the bilge keel4 ,four strakes of the skin plating extending up to the armor shelf had also been forced inward and fractured where they crossed the longitudinal frames4 ,they had parted in the middle for a distance of #h ft41 while some of the butts had been opened so that gashes #b in4 or #c in4 wide appeared between them4 ,the coal had been pulverized and scattered in all directions1 and other internal damage inflicted4 ,nevertheless1 the watertight bulkheads remained intact1 and by confining the influx of water to a single compartment so much buoyancy was preserved that1 though the ship heeled over to starboard and was maimed1 she remained afloat1 and might have continued to fight her guns1 provided always that no injury had been sustained by her machinery1 a point which these experiments do not touch4 ,crippled1 however1 as she was1 it was thought at the time 7and the probability was strengthened by subsequent examination of the ship in dock7 that the coal1 instead of being a protection to the double bottom1 had in reality proved a source of weakness by receiving the energy of the explosion from the outer plating and communicating it to the inner plating1 and so distributing it throughout the submerged portions of the hulk4 ,the question was sufficiently important to demand an experimental solution2 hence the raison d'etre of the present demonstration4 ,the double bottom1 which is about #b ft4 deep1 was consequently kept empty1 and the torpedo placed in immediate contact with it in such a manner that1 being overhung by the contour of the hull1 the ship would feel the full force of the upward as well as the lateral energy of the charge4 ,on other accounts the importance of the experiment was obvious1 for1 although it had been ascertained that torpedo nets were capable of protecting a battle ship from the bursts of the heaviest locomotive and outrigger charges1 it might happen1 of course1 that the nets would be rent or displaced by shell fire or swept away by a grazing ram or even attacked by a double torpedo1 the second passing through the gashes made by the explosion of the first in any case4 ,it was1 therefore1 of urgent necessity that the effect of a torpedo bursting in immediate contact with a ship's bottom should be practically and clearly determined4 ,the charge on ,june #ac was fired just before #e p4m4 in the wake of the boilers1 and it was soon perceived that something of a fatal character had taken place from the appearance of coal dust sweeping up through the hold4 ,the report had not the dull boom to which the spectators had become accustomed4 ,instead of this1 the gun cotton exploded with a sharp1 angry1 whistling noise1 while the manner in which the mud was churned up showed that the force of the rebound was terrific4 ,the ship lifted bodily near the stern1 after which it was seen to leisurely heel over to starboard some eight or ten degrees1 and finally repose1 though not until the tide fell1 upon the mud4 ,the old hulk had been mortally wounded at last4 ,a complete knowledge of the disaster which has overtaken her 7says the correspondent of the ,london ,times1 to which we are indebted for the above particulars7 will not be obtained until a careful investigation has been made of the hull in dock4 ,but1 from a hasty exploration which was conducted on board1 it was evident that the shot had not only dislocated the inner plating of the double bottom1 but had penetrated the bunker compartment1 stored as it was with coal1 that the watertight doors and compartments had ceased to operate1 and that water was flowing into the hull through a hundred crevices4 ,to such an extent was this the case that1 though a strong working party was at hand ready for any emergency1 it was deemed useless to attempt to free the ship of water until her gashes had been temporarily closed from outside4 ,when this has been done1 she will be pumped out and brought into dock for careful examination4 ,from what has been said1 it will be seen that while the explosion of #ie lb4 of gun cotton in actual contact last ,november simply crippled the ,resistance1 the explosion of a like charge at the same spot1 and under approximately the same conditions1 has in this instance not simply disabled1 but really sunk the ship4 99 99 99 99 99 ,,an ,,english ,,car ,,coupling4 ,the new automatic railway coupling illustrated below is the invention of ,mr4 ,richard ,hill1 and has been practically developed by ,mr4 ,b4,h4 ,thwaite1 of ,liverpool4 ,it will be seen that the system is somewhat similar to the parallel motion when in action4 ,the catch and peculiarly shaped hooks slide over the cross and catch bars4 ,these latter turn horizontally on a central pivot attached to the jaw end of the drawbar4 ,the cross catch bars adjust themselves to the direction of the line of pull in the drawbar4 ,the cranking of the drawbar allows for the deflection of the buffer springs4 ,the arrangement of uncoupling1 or throwing hooks out of gear1 is extremely simple and effective4 ,the cranked part of the rod passing across the end of the wagon1 and with handles at each end workable from the #f ft4 way1 is attached to the catch hooks by means of a light chain4 ,on throwing the handle over1 and against the end of the wagon1 the crank moves over and below the center1 lifting up the catch into a position out of range of action1 and from this position it cannot fall except it is released by the shunter4 ,a shackle and links hang from the end of the drawbar for attachment to ordinary wagons4 ,after a long and costly series of experiments the form of coupling shown in illustration was adopted4 ,part of the experimental couplings used were made by the ,hadfield ,steel ,foundry ,company1 but the couplings used at a recent trial at ,gloucester were forged by the ,gloucester ,wagon ,company4 ,illustration3 ,,an ,,english ,,car ,,coupling4 ,the trial couplings were applied to old and worn-out coal wagons1 varying in relative heights and widths of buffers1 and the tests were3 #a4 ,coupling and uncoupling1 and passing coupled round curves of less than two chains radius4 #b4 ,coupling under rapid transit movement and violent shock4 #c4 ,coupling under slow movement1 the wagons being shunted together by two shunters4 #d4 ,wagons brought violently together while the coupling hooks were lifted out of action1 to test the rigidity of the hooks in this position4 #e4 ,tested in competition with the ordinary coupling stock4 ,the trial was a success4 ,the new automatic coupling satisfactorily underwent the various conditions1 and it was proved that3 #a4 ,it can be lifted out of action with one hand and quite easily4 #b4 ,it can be coupled and uncoupled six times as fast as with the pole hook in the daytime4 ,at night this advantage would be considerably increased4 ,the coupling is strong as well as elastic in its parts1 and adjusts itself to the various conditions of traction4--,engineering4 99 99 99 99 99 ,continued from ,,supplement1 ,no4 #eig1 page #ieci4 ,,magazine ,,rifles4 ,chaffee-,reece ,magazine ,rifle4--,we do not insert a drawing of this arm--one of the three selected by the ,american board--as it belongs to the same class and is similar in general construction to the ,hotchkiss4 ,there is1 however1 an important difference in the magazine1 which has no spiral spring1 but is furnished instead with an ingenious system of ratchet bars4 ,one of these carries forward the cartridge a distance equal to its own length at each reciprocal motion of the bolt1 while a second bar has no longitudinal motion1 but prevents the cartridges from moving to the rear in the magazine tube after they have been moved forward by the other bar4 ,the magazine is loaded through an aperture in the butt plate1 the opening of the spring cover of which causes the two ratchet bars to be depressed1 so that the magazine can be filled by passing the cartridges along a smooth middle bar4 ,the act of closing the spring cover again brings the two ratchet bars into play4 ,illustration3 ,,fig4 #i4--,,kropatschek ,,magazine ,,gun ,by means of a cut-off the ratchet bars can be prevented from acting1 and the piece used as a single loader4 ,kropatschek ,magazine ,rifle4--,this rifle1 which is the small arm of the ,french navy1 has a bolt-action rifle resembling the ,gras 7see ,fig4 #i74 ,the magazine is a brass tube underneath the barrel1 as in the ,winchester1 ,vetterli1 ,mauser1 and other rifles of class #a4 ,it contains six cartridges1 while a seventh can be placed in the trough or carrier1 ,t4 ,when the breech is opened by pulling back the bolt1 a projection on the latter strikes the carrier at ,n1 causing its front extremity to raise the cartridge into the position shown in the section4 ,this movement is accelerated by the spring1 ,a1 acting against a knife-edge projection on the trough1 ,t2 in the upper position of the trough1 the spring acts upon one face of the angle1 and upon the other face when in the lower position4 ,on closing the breech1 the bolt pushes the cartridge into the chamber1 and when the handle is locked down to the right1 a part of the bolt presses against a stud1 and thus depresses the trough to be ready to receive another cartridge from the magazine4 ,the magazine can be cut off and the rifle used as a single loader by pushing forward a thumb-piece on the right side of the shoe4 ,the effect of this is that1 on turning down the handle to lock the bolt1 the latter does not act on the stud to depress the carrier1 so that no fresh cartridges are fed up from the magazine4 ,illustration3 ,,fig4 #aj4--,,lee ,,magazine ,,gun ,there is a projection1 ,z1 on the fore part of the carrier1 which keeps the next cartridge from leaving the magazine while the trough is in the upper or loading position4 ,a supplementary cartridge stop1 ,r1 pivoted at ,p and having a spring1 ,l1 underneath it1 acts in conjunction with ,z in retaining the cartridges in the magazine1 and especially in preventing more than one at a time from passing out into the carrier when the latter is depressed2 it also retains the cartridges in the magazine tube while the latter is being filled4 ,lee ,magazine ,rifle4--,this arm 7see ,fig4 #aj71 which occupied the place of honor in the report of the ,american ,board on ,magazine ,guns1 embodied two new principles of considerable importance1 viz41 the central position of the magazine1 and having it detachable with ease1 so that two or more magazines can be carried by the soldier4 ,the breech action of the ,lee does not materially differ in design from other bolt rifles1 except that the bolt is in two pieces only--the body1 or bolt proper1 and the hammer or cocking-piece4 ,the firing pin1 or striker1 is screwed into the hammer2 the spiral main spring1 which surrounds the striker1 is contained in a hollow in the body4 ,the handle is placed at the rear end of the bolt1 and bent down toward the stock1 so as to allow the trigger to be reached without wholly quitting hold of the bolt4 ,the extractor is so connected with the bolt head as not to share the rotation of the latter when the handle is turned down into the locking position4 ,when the handle is turned up to unlock the bolt1 the hammer is cammed slightly to the rear1 by means of oblique bearings on the bolt and hammer1 so as to withdraw the point of the striker within the face of the bolt4 ,this oblique cam action also gives great power to the extractor at first starting the empty cartridge case out of the chamber4 ,the magazine1 ,m1 is simply a sheet iron or steel box of a size to hold five cartridges1 but there seems no reason why it should not be of larger dimensions4 ,it is detachable from the rifle1 and is inserted from underneath into a slot or mortise in the stock and in the shoe1 in front of the trigger guard4 ,a magazine catch1 ,c1 just above the trigger guard1 engages in a notch1 ,n1 in the rear of the magazine1 the projection1 ,l1 first entering a recess prepared for it in the shoe4 ,there is a magazine spring1 ,d1 at the bottom of the magazine box which pushes the cartridges up into the shoe4 ,the point of the top cartridge is pushed into the projection1 ,l1 and this keeps the lower cartridges in their places in the box while the latter is detached2 when the magazine is inserted in the rifle1 the withdrawal of the bolt causes the top cartridge to be slightly drawn back1 so that it is now free to be fed up into the shoe by the magazine spring1 ,d4 ,there is a later pattern of magazine1 which has its front face quite plain1 with no projection1 ,l1 as the magazine catch was found sufficient to hold the box in its place4 ,to prevent the cartridges being pressed out of the magazine before the latter is inserted in the rifle1 there is a strong spring placed vertically in one side of this box1 the curved upper end of which bears upon the top cartridge2 when the magazine is in its place in the shoe1 this side spring is so acted upon that it ceases to hold down the cartridges in the box4 ,to use the rifle as a single loader1 formerly the magazine had to be detached1 when a spring plate in the shoe1 which is pushed aside by the insertion of the magazine1 starts back into its place and nearly fills the magazine slot1 so as to prevent cartridges falling through to the ground when fed into the chamber by hand4 ,the later pattern1 however1 has two notches on the magazine for the catch1 ,c1 to engage in4 ,when the magazine is inserted in the slot only as far as the upper notch1 the rifle can be used only as a single loader1 but on pressing the box home to the second notch1 the magazine immediately comes into play4 ,the magazine can be released from the slot by an upward pressure on the lower projecting end of the magazine catch1 ,c1 which is covered by the trigger guard4 ,improved ,lee4--,this rifle is precisely similar in principle to the ,lee1 the chief difference being that the magazine is permanently fixed in its slot underneath the shoe1 and in front of the trigger guard4 ,the cartridges are inserted from above4 ,there is a stop by means of which the cartridges can be prevented rising up into the shoe1 and which forms a sort of false bottom to the slot in the latter1 so that the arm can be used as a single loader4 ,lee-,burton4--,the bolt action is the same as the ,lee1 but the box magazine is attached to the right side of the shoe1 instead of being underneath1 as in that rifle4 ,when the magazine is raised to its higher position1 the cartridges pass successively into the shoe by the action of gravity alone1 and are thus pressed home into the chamber by the closing of the bolt4 ,illustration3 ,,fig4 #aa4 ,a number of the ,lee-,burton and improved ,lee rifles are now being manufactured for issue to the troops1 in order to undergo experimental trials on an extended scale4 ,several other magazine rifles have the box central magazine1 but placed in different positions as regards the shoe and the axis of the bore4 ,in the original pattern of the ,jarman 7,sweden and ,norway71 the magazine is affixed to the upper part of the shoe1 inclined at a considerable angle to the right hand 7see vertical cross section1 ,fig4 #aa74 ,here the operation of gravity obviates the necessity of a magazine spring1 but the magazine was found to be very much in the way and liable to be injured4 ,it has therefore been replaced by a magazine underneath the barrel1 as in the ,kropatschek and other rifles4--,engineering4 7,to be continued47 99 99 99 99 99 ,,preservative ,,liquid4 ,for a few weeks' preservation of organic objects in their original form1 dimensions1 and color1 ,prof4 ,grawitz recommends a mixture composed of #b ounces of chloride of sodium1 #b drachms of saltpeter1 and #a pint of water1 to which is to be added #c per cent4 of boric acid4--,annales des ,travaux ,publics4 99 99 99 99 99 ,,kent',s ,,torsion ,,balance4 ,the ,united ,states ,torsion ,balance ,company1 of ,new ,york1 has recently brought before the public a new form of balance which presents so many ingenious and excellent features that we illustrate it below1 on the present page4 ,the instrument in its simplest form is shown in ,fig4 #a4 ,it consists of a beam1 ,a1 which is firmly attached to a wire or band1 ,b1 at right angles to it1 and which wire is tightly stretched by any convenient means4 ,then1 since the wire and beam are both horizontal in their normal position1 and since the center of gravity of the beam is immediately above or below the middle line of the wire1 the torsional resistance of the latter tends to keep the beam horizontal and to limit its sensitiveness4 ,when the beam is deflected out of its horizontal position and the wire thereby twisted1 the resistance to twisting increases with the arc of rotation4 ,to counteract this resistance and to render the beam sensitive to a very slight excess of load at either end1 a poise1 ,d1 is attached to the beam by a standard1 ,c1 which poise carries the center of gravity of the structure above the axis of rotation4 ,this high center of gravity tends to make the beam top heavy1 or in unstable equilibrium4 ,by properly proportioning the poise and its distance above the wire to the resistance of the wire1 the top-heaviness may be made to exactly neutralize the torsional resistance1 and when this is done the beam is infinitely sensitive4 ,illustration3 ,,kent',s ,,torsion ,,balance4 ,fig #a4 ,the moment of the weight or its tendency to fall increases directly as the sine of the arc of rotation1 while the torsional resistance increases as the arc1 and for small angles the sine and the arc are practically equal4 ,when arranged as in ,fig4 #a1 the scale is balanced only when the center of gravity of the structure is vertically above the middle line of the wire1 and the support of the scale must be leveled in the direction of the beam1 so as to cause the center of gravity to take this normal position4 ,after the scale is thus leveled1 if from any cause whatever1 such as shifting the scale on a table1 or shifting the table itself1 the scale support is thrown out of level1 the center of gravity of the poise and beam is shifted from the vertical line above the support1 and its moment immediately becomes greater than the torsional resistance1 and the beam tips out of balance1 and cannot be used as a correct scale until the support is again leveled4 ,illustration3 ,,kent',s ,,torsion ,,balance4 ,fig #b4 ,in spite of all the foregoing facts1 it was reserved for the ,encyclopedia ,britannica1 in its ninth edition1 to use the following as the result of its condensed wisdom3 ,in the torsion balance proper1 the wire is stretched out horizontally1 and supports a beam so fixed that the wire passes through the center of gravity4 ,hence the elasticity of the wire plays the same part as the weight of the beam does in the common balance4 ,an instrument of this sort was invented by ,ritchie1 for the measurement of very small weights1 and for this purpose it may offer certain advantages2 but clearly if it were ever to be used for measuring larger weights1 the beam would have to be supported by knife edges and bearing1 and in regard to such applications therefore 7as in serious gravimetric work71 it has no raison d'etre4 ,illustration3 ,,kent',s ,,torsion ,,balance4 ,fig #c4 ,this would seem to settle the whole case1 for if the encyclopedia says it has no reason to be1 then1 like the edict of the ,mikado1 it is as good as dead1 and if that is the case1 ,why not say so8 ,on the contrary1 the torsion balance seems very much alive4 ,but as it is not very generally known1 perhaps the early history of this form of balance1 briefly sketched1 may prove of interest4 ,one of the first forms of the torsion balance which met the disapproval of the ,encyclopedia ,britannica was attended with the difficulty that the pivoted wires were attached directly to the bifurcated ends of the beam1 and could not be tensioned without bending these ends unless the beam was made so heavy as to interfere with its employment in delicate weighing4 ,illustration3 ,,kent',s ,,torsion ,,balance4 ,fig #d4 ,the next step was the substitution of light forms stiffened by the wires being tensioned over them4 ,this was the invention of ,professor ,roeder1 recently deceased4 ,the next step was the common counter scale1 and then that form of letter scale in which one of the bands acts as a fulcrum and the other as a pivot4 ,after ,professor ,roeder's death1 ,dr4 ,alfred ,springer1 of ,cincinnati1 continued perfecting this invention1 and with marked success--scales not intended for anything but the weighing of the ordinary articles of a grocery store working so accurately that up to #ej lb4 two grains would turn the balance4 ,as will be noted1 this balance dispenses entirely with knife edges1 and this statement carries with it the gist of its entire merit4 ,there is no friction1 and the elegance of the work and the nice adjustments of the parts struck the writer at once4 ,illustration3 ,,kent',s ,,torsion ,,balance4 ,fig #e4 ,the prescription scale and the proportional scale 7see ,fig4 #d7 are particularly interesting4 ,the former is sensitive to #a_/fd of a grain1 and the latter1 invented by ,mr4 ,kent1 is a most ingenious method for weighing1 by which1 in a small compass 7#aj in4 by #d in4 by #c in471 we have a balance capable of weighing #c lb4 avoirdupois by thirty-seconds of an ounce4 ,for ordinary balances on the torsion system1 in which extreme sensitiveness is not needed1 the trouble caused by change of level of the scale is insignificant2 but it becomes a matter of importance in more sensitive scales1 such as fine analytical balances in places where it is impossible to keep the table or support of the scale level1 for instance on shipboard4 ,to counteract this effect of the change of level1 ,dr4 ,alfred ,springer devised the system which is shown in its most elementary form in ,fig4 #b4 ,an additional beam1 ,e1 with wire1 ,f1 and poise1 ,h1 on support1 ,c1 were added to the balance1 and connected to it by a jointed connecting piece1 ,j4 ,the moment of the structure1 ,e ,c ,h1 about its center of rotation was made equal to the moment of ,a ,c ,d about the center4 ,the wires1 ,b and ,f1 are attached at their ends to supports which are both rigidly connected to the same base or foundation4 ,if this base1 the normal position of which is horizontal1 is tipped slightly1 the weights1 ,c and ,h1 will both tend to fall in the same direction4 ,but suppose the right hand end of the base is raised1 causing both of the weights to tip to the left of the vertical1 ,d1 tending to fall over1 the left tends to raise the right hand end of the beam1 and the connecting piece1 ,j ,h1 also tending to fall to the left1 tends to lower the left hand end of ,e and the piece1 ,j4 ,the moments of the structure1 ,e ,c ,h1 and ,a ,b ,d being equal1 and one tending to raise ,j and the other to lower it1 the effect will be zero1 and ,j will remain in its normal position4 ,it is not at all necessary1 however1 to have the weights and dimensions of the structure1 ,e ,c ,h1 equal to those of ,a ,b ,d4 ,all that is necessary is that the components of the weight of each part of the structure which act vertically on ,j shall be equal and opposite4 ,for1 if the left end of the beam1 ,e1 is made shorter than the right end of the beam1 ,a1 a given angle of rotation of the beam1 ,a1 will cause a greater-angle of rotation of ,e1 consequently will tip the weight1 ,h1 further from the vertical than the weight1 ,d1 is tipped1 and in that case the weight1 ,d1 must be made smaller than ,h1 to produce an equal and opposite effect upon ,j4 ,in practice it is convenient to make the beam1 ,e1 only one-fifth to one-twentieth as long as ,a1 and to correspondingly reduce the weight1 ,h1 relatively to ,d4 ,in this case1 on account of the angle of rotation of the beam1 ,e1 being greater than the angle of rotation of ,a1 the beam1 ,e1 becomes a multiplier of the indications of the primary beam1 ,a4 ,mr4 ,kent has devised a modification of ,dr4 ,springer's system1 which is shown in ,fig4 #c4 ,it is applied in those varieties of the torsion balance in which there are two parallel beams1 connected by either four or six wires4 ,the wire1 ,f1 carrying the secondary beam1 ,e1 and poise1 ,h1 instead of being carried on an independent support1 rigidly attached to the base1 as above described1 is attached directly to a moving part of the balance itself1 and preferably to the two beams4 ,in ,fig4 #c1 ,t ,t ,t are trusses over which are tightly stretched the wires1 ,b ,b ,b4 ,a ,a' are two beams rigidly clamped to the wires2 t is another truss with stretched wire1 ,f ,f4 ,the upper wire1 ,f'1 is attached by means of a flexible spring and standard1 ,s1 to the upper beam1 and the lower wire is attached either directly or through a standard to the lower beam4 ,the secondary poise1 ,h1 is rigidly attached to the truss1 t4 ,the secondary beam1 ,e1 is also rigidly attached to the truss1 and acts as a multiplying beam4 ,the secondary structure thus completely fills two functions3 ,first1 that of multiplying the angle of rotation and thereby increasing the apparent sensitiveness of the scale1 and1 second1 that of overcoming the effect of change of level4 ,the secondary beam may be dispensed with if a multiplier is not needed1 and the secondary truss1 t1 with its standard and counterpoise1 ,h1 used alone to counteract the effect of change of level4 ,fig4 #e shows a modification of this extremely ingenious arrangement4--,engineering4 99 99 99 99 99 ,,link ,,belting4 ,footnote3 ,from a paper read before the ,technischen ,verein of ,new ,york1 ,may #bh1 #ahhg4 ,by ,,chas4 ,a4 ,,schieren4 ,the old saying that there is nothing new under the sun may well be applied to leather link belting4 ,it is generally believed that these belts are of recent invention1 but that is an error4 ,they are over thirty years old4 ,mr4 ,c4,m4 ,roullier1 of ,paris1 experimented that long ago with small leather links one and one-half inches long by three-quarters of an inch wide4 ,these links had two small holes at equal distances apart1 and were joined with iron bolts1 which were riveted at the ends1 thus making a perfectly flat surface1 and in that way forming a belt entirely of leather links4 ,mr4 ,roullier's idea was to economize2 he therefore utilized the material left over from the manufacture of flat belting4 ,he perfected his belt and came to this country in #ahfb1 when he patented the article here and tried to introduce it4 ,at first it produced quite a sensation1 and many tests were made1 but it was soon found that ,roullier's belts were not suited to running our swift motion machinery1 and they were therefore abandoned as impracticable4 ,mr4 ,roullier then introduced his invention into ,england1 where he met with some success1 as his belt was better suited to ,english slow motion machinery4 ,these belts are now largely used in ,england1 many good improvements have been made in them1 and almost every belt maker in ,great ,britain manufactures them4 ,mr4 ,jabez ,oldfield1 of ,glasgow1 has the reputation of making the best and most reliable link belt in ,great ,britain4 ,he has also the reputation of being the originator of these belts4 ,this is1 however1 an error1 the credit of the invention belonging1 as we have said1 to ,mr4 ,roullier4 ,mr4 ,oldfield1 nevertheless1 has invented many useful machines for cutting and assorting the links4 ,he has also introduced improved methods for putting the links together4 ,for more than twenty years after ,mr4 ,roullier's visit1 nothing was done with leather link belting in this country4 ,in #ahhb1 however1 ,mr4 ,n4,w4 ,hall1 of ,newark1 ,n4,j41 patented a link belt1 composed of leather and steel links4 ,his method was to place a steel link after every third or fourth leather one1 in order to strengthen the belt4 ,in practical use this belt was found to be very defective1 because the leather links soon stretched1 and thus all the work had to be done by the steel links4 ,the whole strain coming thus upon the steel links1 they in course of time cut through the bolts and thus broke the belt to pieces4 ,so this invention proved worthless4 ,in #ahhd a ,chicago belt company obtained a patent on another style of link belt4 ,in this belt all the little holes in the links were lined with metal1 similar to the holes in laced shoes4 ,this produced an effect similar to that produced by ,hall's patent4 ,the metal lining of the holes cut the bolts into pieces by friction and thus ruined the belt4 ,therefore this patent proved a failure also4 ,after all these failures it fell to our lot to improve these belts so that they may now be worked successfully on our ,american fast running machinery4 ,during the past two years we have made and sold over five hundred leather link belts1 which are all in actual use and doing excellent service1 as is proved by many testimonials which we have received4 ,our success with these belts has been so surprising that we think we have found1 at last1 the long looked for missing link1 not in ,darwinism1 however1 but in the belting line4 ,we prophesy a great future for these belts in this country4 ,how have we attained such success8 ,first3 ,we found that ,roullier made a mistake in using leather offal1 as1 in the links of an iron chain1 if one link is weak or defective1 the whole chain is worthless1 so in link belts1 if one or two links are weak or made of poor material1 the whole belt is affected by them4 ,it is therefore of vital importance that only the best and most solid leather be used in making the links2 second1 the leather must be made very pliable1 but at the same time its toughness and tenacity must not be injured1 or it will stretch and break4 ,illustration3 ,,fig #a4 ,these things are of great importance1 and are the principal reasons for the failures of all former efforts4 ,the leather which ,roullier used was stiff1 hard1 and husky4 ,he believed that the harder the link the greater its tensile strength1 but upon actual test this was found to be a fatal error4 ,our leather links are saturated with a mixture of tallow1 neatsfoot oil1 etc4 ,this makes them very pliable and increases their toughness1 so that they will stand a strain three times as great as a piece of hard rolled sole leather4 ,in manufacturing this belt1 the joining together is important4 ,the links must be accurately assorted as to thickness1 and the outer links countersunk1 to admit the bolt4 ,then the most valuable improvement of all is our ,american joint 7see ,fig4 #a74 ,by close inspection you will observe that it is absolutely necessary to use half length bolts for the width of wide leather link belts4 ,examine ,figs4 #b and #c4 ,in the latter you will notice one length of bolt placed on a round faced pulley4 ,that belt must either bend or break1 and in any case it will not give satisfaction2 but1 on the other hand1 examine ,fig4 #b2 here two half length bolts are used1 and ingeniously joined in the center4 ,it gives just pliability enough to lay the belt flat upon the pulley4 ,we experimented for some time before perfecting this important improvement4 ,we also took out four patents for different methods of joining1 but abandoned them all and adopted the ,american joint system 7,fig4 #a7 as the most efficient1 simple1 and reliable4 ,it gives the belt an unbroken flat surface and is far superior to anything so far introduced for that purpose4 ,we have not stopped at flat link belting1 but have turned our attention to manufacturing round solid leather link belting1 and believe that we have almost attained perfection in that line4 ,as the illustrations clearly show1 there is quite a demand for inch and upward solid round belting1 and the difficulty always has been to join such a belt together4 ,all steel hooks1 etc41 do not seem to satisfy4 ,this1 our new invention1 is so simple that it hardly needs explanation4 ,a belt of this kind can be taken apart in a short time1 and shortened or lengthened at pleasure4 ,now1 ,mr4 ,president and gentlemen1 ,i shall be glad to answer any questions in reference to these link belts1 or give any further explanation you may desire4 ,question4--,can these link belts be used on dynamos for electric lights8 ,answer4--,yes4 ,in ,england they are used almost exclusively on dynamos4 ,however1 they run only #gjj revolutions per minute there1 whereas our slowest dynamo runs #a1ajj4 ,illustration3 ,fig4 #b4 ,quest4--,would you advise link belts for high rate of speed8 ,ans4--,no2 they give better results on slow running machinery4 ,quest4--,have these belts any special advantage over flat leather belting8 ,ans4--,yes1 decidedly4 ,when belts are run half crossed1 or what is termed quarter turn1 it is very hard to make flat belts lie perfectly even on the pulleys4 ,these link belts1 however1 cover the entire face of the pulley 7see illustration71 and therefore are superior for that purpose4 ,illustration3 ,fig4 #c4 ,quest4--,why do they give better results when run slow8 ,ans4--,partly because of their great weight over ordinary belting1 also their grip power is stronger when run slow4 ,no belt is superior to them for slow1 hard working machinery4 ,quest4--,are they more expensive than ordinary flat belting8 ,ans4--,not when compared to the work they can accomplish4 ,illustration ,quest4--,can they be run in wet places1 such as mines1 etc48 ,ans4--,yes2 by waterproofing the leather1 no cement being used as in flat belts4 ,the links can be made positively waterproof4 ,we have furnished paper mills1 tanneries and bleacheries1 and other exposed places with waterproof link belts1 and all have been entirely satisfactory so far4 ,quest4--,can they be run on ordinary flat pulleys8 ,ans4--,yes2 our ,american joint link belt can be run on any straight or rounded pulley1 whether made of iron1 paper1 or wood1 and being all endless they run much smoother than other belting4 ,illustration3 ,,english ,,hinge ,,joint3 ,quest4--,how are they made endless8 ,ans4--,by a very simple process 7see illustration71 and takes almost less time than lacing a flat belt4 ,all that is necessary is to take both ends and interlock the links1 then pass the bolt through and rivet it1 and when you wish to shorten the belt proceed likewise3 ,file off the end of the bolt and take out1 or add rows of links at pleasure and rejoin it again4 ,illustration3 ,fig4 #d is a complete round link belt4 ,quest4--,what is the relative strength of a link belt compared to flat belting8 ,ans4--,nothing definite has yet been ascertained4 ,we are preparing a table showing results1 and so far we can report that they can stand about twice the strain of double flat belts4 ,a four inch link belt one inch thick is able to do the work of an eight inch flat double belt4 ,illustration3 ,fig4 #e is a side view4 ,quest4--,explain the advantage of your ,american joint over the ,english hinge4 ,ans4--,the ,american joint gives a perfect unbroken surface of entire width of belt1 whereas the ,english hinge joint makes two half widths1 and whenever a sudden change of power occurs and the belt runs half way off the pulley1 it will catch at the edge and tear everything to pieces4 ,illustration3 ,fig4 #f is an end view4 ,quest4--,have you a table or schedule of their weight per square foot8 ,ans4--,yes4 ,the following is as near as we can estimate the weight of leather link belting per square foot3 #a inch thick1 about #e lb4 per sq4 ft4 #g_/h #d #c_/d #d #e_/h #c ,upon motion a vote of thanks was passed1 and the paper read ordered to be printed4 ,illustration3 ,fig4 #g is a single link4 99 99 99 99 99 ,a ,,new ,,process ,,of ,,casting ,,iron ,,and ,,other ,,metals ,,upon ,,lace1 ,,embroideries1 ,,fern ,,leaves1 ,,and ,,other ,,combustible ,,materials4 ,footnote3 ,abstract of a paper read before the ,franklin ,institute1 ,april1 #ahhg4--;,j4,f4,i4 ,by ,a4,e4 ,,outerbridge1 ,,jr4 ,the art of making charcoal--if1 indeed1 so crude a process is worthy of being dignified by the name of an art--dates back to a remote antiquity1 and has been practiced with but little change for hundreds of years4 ,it is true that some improvements have been recently made1 but these relate to the recovery of certain volatile by-products which were formerly lost4 ,every one is familiar with the appearance and characteristics of ordinary charcoal1 yet ,i hope to show you this evening that we still have something new to learn about its qualities and the unexpected practical uses to which it may be applied4 ,we commonly regard charcoal as a brittle1 readily combustible substance1 but we have before us specimens in which these qualities are conspicuously absent4 ,here is a piece of carbonized cotton sheeting1 which may be rolled or folded over without breaking1 and1 as you see1 when placed in the flame of a ,bunsen burner1 the fibers may be heated white hot in the air1 and when removed from the flame1 the material shows no tendency to consume4 ,here1 again1 we have a piece of very fine lace1 which has been similarly carbonized1 and displays the same qualities of ductility and incombustibility4 ,these carbonized fabrics may be subjected to much more severe tests with impunity2 and when ,i tell you that they have been exposed to a bath of molten iron without injury1 you will readily admit that they possess some qualities not ordinarily associated with charcoal4 ,when removed from the mould in which they were placed after the iron casting had cooled1 not a single fiber was consumed1 but upon the face of the casting there was found a sharp and accurate reproduction of the design1 thus forming a die4 ,this die may be used for a variety of purposes1 such as embossing leather1 stamping paper1 sheet metal1 etc41 or for producing ornamental surfaces upon such castings4 ,some of the carbonized fabrics displayed upon the table are almost as delicate as cobwebs1 and one would naturally suppose that when a great body of molten metal is poured into a mould in which they are placed1 they would be torn to fragments and float to the surface even though they were unconsumed1 yet such is not the case4 ,i have found in practice that the most delicate fabrics may be subjected to this treatment without danger of destruction1 and that no special care is needed either in preparing the mould or in pouring the metal4 ,by the aid of the megascope1 the enlarged images of some of these castings1 showing the delicate tracery of the patterns1 will now be projected upon the screen1 and you can all see how perfectly the design is reproduced4 ,in these experiments1 the mould was made in green sand in the ordinary manner1 and the fabric laid smoothly upon one face1 being cut slightly larger than the mould1 in order that it might project over the edge1 so that when the moulding flask was closed1 the fabric was held in its proper position4 ,as the molten metal flowed into the mould1 it forced the fabric firmly against the sand wall1 and when the casting was removed1 the carbonized fabric was stripped off from its face without injury4 ,in this way several castings have been made from one carbonized material4 ,these castings are as sharp as electrotypes1 whether made of soft fluid iron or of hard1 quick-setting metal4 ,this peculiarity is owing to the affinity between molten iron or steel and carbon4 ,the molten metal tends to absorb the carbon as it flows over it1 thus causing the fabric to hug the metal closely4 ,it is somewhat analogous to the effect of pouring mercury over zinc4 ,you know that when mercury is poured upon a board1 it runs in a globular form1 it does not wet the board1 so to speak2 but when poured upon a plate of clean zinc1 it flows like water and wets every portion of the zinc1 or1 as we say1 it amalgamates with the zinc4 ,so when molten iron is poured into an ordinary sand mould1 which has been faced with this refractorily carbonized fabric1 it wets every portion of it1 tending to absorb the carbon1 and doubtless would do so if it remained fluid long enough1 but as the metal cools almost immediately1 there is no appreciable destruction of the fibers4 ,the casting which ,i shall now exhibit represents a very interesting and novel experiment4 ,in this case1 the piece of lace1 having open meshes a little larger than a pin's head1 instead of being laid upon one face of the mould1 was suspended in it in such a way as to divide it into two equal parts4 ,two gates or runners were provided1 leading from the sinking head to the bottom of the mould1 one on each side of the lace partition4 ,the molten iron was poured into the sinking head1 and flowing equally through both runners1 filled the mould to a common level4 ,the lace1 which was held in position by having its edges embedded in the walls of the mould1 remained intact4 ,when the casting was cold1 it was thrown upon the floor of the foundry and separated into two parts1 while the lace fell out uninjured1 and the pattern was found to be reproduced upon each face of the casting4 ,the question naturally arises1 ,why did not the iron run through the holes and join together8 ,the answer may be found in the fact that the thin film of oxide of iron1 or skin1 as it is popularly called1 which always forms on the surface of molten iron1 was caught in these fine meshes1 and thus prevented the molten metal from joining through the holes4 ,i have repeated the experiment a number of times1 and find that the meshes must be quite small 7not over one fiftieth of an inch71 otherwise the metal will reunite4 ,i think that this observation explains the cause of many obscure flaws found in castings1 sometimes causing them to break when subjected to quite moderate strains4 ,we frequently find little cold shot1 or metallic globules1 embedded in cast iron or steel1 impairing the strength of the metal1 and it has long been asked1 ,what is the cause of this defect8 ,the pellicles have been carefully analyzed1 under the supposition that they might be alloys of iron and nickel1 or some other refractory metal1 but the analysis has failed to substantiate this theory4 ,is it not probable that in the process of casting1 little drops of molten metal are sometimes splashed out of the stream1 which immediately solidify and become coated with a skin of oxide1 then falling back into the stream of rapidly cooling metal1 they do not remelt1 neither do they weld or amalgamate with the mass1 owing to this protective coating1 thus forming dangerous flaws in the casting8 ,the process of carbonizing the delicate fabrics1 leaves1 grasses1 etc41 is as follows3 ,the objects are placed in a cast iron box1 the bottom of which is covered with a layer of powdered charcoal or other form of carbon1 then another layer of carbon dust is sprinkled over them1 and the box is covered with a close fitting lid4 ,the box is next heated gradually in an oven1 to drive off moisture1 and the temperature slowly raised until the escape of blue smoke from under the lid ceases4 ,the heat is then increased until the box becomes white hot4 ,it is kept in this glowing condition for at least two hours4 ,it is then removed from the fire1 allowed to cool1 and the contents are tested in a gas flame4 ,if they have been thoroughly carbonized1 they will not glow when removed from the flame1 and the fibers may even be heated white hot before consuming4 ,of course1 the method employed to carbonize the materials is suspectible of variation1 but the scientific principles involved are unchangeable1 viz43 7#a7 ,partial exclusion of air and substitution therefor of a carbon atmosphere4 7#b7 ,slow heating to drive off moisture and volatile elements4 7#c7 ,intense and prolonged heating of the partly charred objects to eliminate remaining foreign elements1 and to change the carbon from the combustible form of ordinary charcoal to a highly refractory condition4 ,illustration ,,note4--,fig4 #a is photographed from a white iron casting made upon carbonized coarse lace2 the lower portion of the plate shows the lace embedded in the iron4 ,fig4 #b is a casting in gray iron upon lace laid on an iron plate4 ,fig4 #c is a casting in hard iron upon lace laid on dand4 ,fig4 #d is a casting in gray iron upon a piece of thin summer dress goods with machine embroidery4 99 99 99 99 99 ,,recent ,,progress ,,in ,,gas ,,engineering4 ,at the recent meeting of ,scottish gas managers ,mr4 ,a4 ,macpherson1 of ,kirkcaldy1 the chairman1 said3 ,,the ,,regenerative ,,system ,,of ,,retort ,,firings4 ,for me to attempt1 with the time at my disposal1 to do full justice to many important points which have cropped up since our last meeting1 and which will1 no doubt1 have been engaging your individual attention1 would be impossible4 ,but ,i think there can be no doubt that1 although at our last meeting we had a very full and interesting discussion on the different systems of regenerative retort settings1 still we might very profitably spend a little time to-day in hearing the experience of those who have had some of the systems introduced into their works since then1 or who may have gained further experience with the system they were then working1 or have introduced improvements or modifications thereon4 ,for the purpose of inducing a discussion on this subject1 ,i will give you the result of the working of the bench of retorts which ,i erected three years ago on the ,siemens system4 ,as ,i stated last year1 my experience up to that time had not been altogether a happy one1 but one of sunshine and cloud alternately4 ,i am glad to be able to say1 however1 that since then ,i have had nothing but the utmost satisfaction in the working of the regenerative settings4 ,the chief difficulties ,i have before experienced were of a mixed nature--choked ascension pipes1 entailing considerable loss of gas2 the choking of the orifices from which the secondary heated air issued to join the producer gas2 and the eating away1 in a scooped-out sort of fashion1 of the brick lining of the producers at the points where the primary air entered4 ,these1 ,i am pleased to be able to say1 ,i am now completely clear of2 and this has had the effect of converting what was before a considerable source of annoyance and anxiety into as perfect a working bench of retorts as any one could desire4 ,the results ,i have obtained have caused me much surprise1 being far in excess of anything ,i ever anticipated2 and the saving effected will materially assist in compensating for the greatly reduced value of residuals4 ,i may state that ,i have used #cj per cent4 of fuel on an average1 saved from #be to #cj per cent4 on stokers' wages1 and increased my production of gas per ton of coal2 while the regularity of the heats was a pleasure to look upon4 ,as showing what ,i have been able to accomplish1 ,i will give you a few details4 ,i was able regularly to produce #aj1jjj cubic feet of gas per mouthpiece in #bd hours--the size of my retorts being #ah by #ac inches by #i feet long1 inside measure2 and on a sudden dullness coming on1 with an increase of first class cannel ,i produced from #cc retorts #ceg1jjj cubic feet1 or at the rate of #aa1ejj feet per mouthpiece in #bd hours4 ,with #cb retorts ,i made as much gas as would have required #db retorts to produce on the old system4 ,but ,i know that even this can be excelled2 and ,i am aware that there are works where1 by the introduction of retorts measuring #ba by #ae inches1 instead of #ah by #ac inches--and which1 ,i may say1 can be put quite easily into the same arch--a production of #ab1jjj cubic feet per mouthpiece can be obtained4 ,this will1 of course1 still further reduce the cost of production4 ,with such an experience1 gentlemen1 ,i think it is almost needless for me to add that ,i am a strong advocate of the regenerative system4 ,i have often heard it asked1 ,but can the system be profitably adapted to small works8 ,in answer to this1 ,i will say ,i have proved that it can4 ,during last summer the manager of a small gas works in my neighborhood called on me regarding the working of this system1 and expressed a desire1 if it was at all possible to adapt it to his present settings without much expense1 to try it4 ,i must say ,i admired his progressive spirit and pluck2 and1 after a somewhat lengthy conversation with him1 during which ,i gathered the full details of his working and his requirements1 ,i determined to encourage him in his desire to prove if it could be successfully applied to a works of the size mentioned4 ,the present setting consisted of three semicircle retorts in one arch2 and one of his stipulations to me was3 ,you must so contrive the setting that if it should prove a failure ,i can reconvert it into the old system in a few hours4 ,i at once saw that the stipulation was reasonable1 or he might be caught in a fix in midwinter4 ,but1 with true ,scotch caution and forethought1 he was1 while anxious to experiment1 determined not to be caught napping4 ,after some consideration1 ,i prepared a sketch for him of how ,i thought it could be done1 and at the same time comply with his stipulation2 and having received full explanations1 he set about it1 and has had it working now for something like six months4 ,his experience has been somewhat similar to that of most of those who have gone in for the new system4 ,it did not answer very well at first4 ,but after a little manipulation and experience in the proper working and management1 it is now acting in first rate style1 and is saving fuel1 with better and more regular heats2 and this although it is not constructed in such a way as to yield the best possible results1 owing to the before mentioned stipulation having to be considered and allowed for in construction4 ,in answer to an inquiry ,i made the other day1 the gentleman referred to informed me that he has now had this setting in operation for six months4 ,he has three retorts1 #ad by #af inches1 and #h feet long1 in an oven carbonizing #b cwt4 of coal every four hours2 the heats are higher and more regular2 and the retorts easier kept clear of carbon4 ,the coke drawn from the top retort is sufficient for fuel4 ,my oven would hold four retorts2 and the same fuel would heat this number just as well as the three4 ,i used only the coke from ,cowdenheath parrot coal for this setting2 but had to mix it with ,burghlee coke for the old system of setting4 ,no doubt most of you will have noticed the satisfactory results obtained by ,mr4 ,hack1 of the ,saltley ,gas ,works1 ,birmingham1 and by ,mr4 ,mc,minn1 of ,kensal ,green1 with the furnaces employed by them for gaseous firing without recuperation1 whereby they are enabled to save fuel and carbonize more coal per mouthpiece than with the old system4 ,still they admit that the saving by this setting is only in fuel1 with increased production1 but without any economy of labor--one of the points in favor of regenerative setting being a saving of at least #be per cent4 in the latter respect4 ,even where regenerative settings cannot be had1 ,i think the system of using gaseous fuel is well worthy the attention of managers2 the expense of altering the existing settings to this method being very small4 ,,improvements ,,in ,,gas ,,purification4 ,i must now1 however1 pass on to some other topics4 ,after the proper production of the gas1 we have still the processes of purification to consider1 and how this operation can best be effected at the smallest cost1 combined with efficiency and the least possible annoyance to residents in the immediate vicinity of gas works4 ,i think all gas engineers are agreed that in ammoniacal liquor we have a useful and powerful purifying agent1 although each one may have his own particular idea of how this can be most efficiently applied--some advocating scrubbers1 others washers4 ,but these are things which each one must determine for himself4 ,but in whatever way it is applied1 we know that it can be profitably used for this purpose2 and ,i am not without hope that it may soon be found possible to remove nearly all the impurities by this means4 ,at present1 however1 this is not so4 ,and consequently we have a variety of other methods employed for the complete removal of the impurities4 ,but1 by whatever means it is effected1 it is unquestionably the duty of the gas engineer to send out to the public an article from which the whole of the impurities have been removed4 ,in ,scotland1 no doubt1 our chief purifying material is lime1 although ,i know that several of our friends have for some time been using oxide of iron1 and perhaps they will favor us with their experience and a statement of the relative cost of lime and oxide4 ,i am not aware that either the ,hawkins method or the ,cooper coal liming process has yet received a trial from any ,scotch gas engineer4 ,,burners ,,and ,,regenerative ,,lamps4 ,but even after we have been able to produce and send out gas of the greatest purity1 our troubles are frequently only beginning1 as1 very often1 consumers do not use1 but simply waste and destroy the gas by bad burners and fittings4 ,nothing1 however1 will convince them that they are in any way to blame for the light being poor4 ,i am certainly of opinion that gas companies would do the public a service in supplying them with suitable burners for the quality of gas that is being sent out for consumption4 ,i have myself for some years adopted this policy1 and almost invariably find that complaints cease and consumers are pleased with the results4 ,we have now also so large a number of really good regenerative lamps which give excellent results1 and can be made in a great variety of very neat and ornamental designs1 that we ought to endeavor to the utmost of our power to introduce them to the public1 and1 if possible1 induce them to use them not only in halls and similar places1 but in their dwelling houses1 as with these lamps a most thorough and efficient system of ventilation can be carried out1 by which the heat that is so much complained of in gas-lighted apartments is reduced to a minimum1 and the atmosphere of such apartments is rendered healthy and agreeable4 ,with such improved lamps at our command1 ,i think we have nothing to fear from the competition of the electric light1 which during the past year has not made any very startling advance--generally attributed by electricians to the restrictive legislation under which they have been placed4 ,let us hope this is now about to be removed4 ,i am sure we all rejoice that such is the case1 as all we want is a fair field and no favor4 ,we can with confidence await the result4 ,,the ,,welsbach ,,gas ,,light4 ,in the mean time1 however1 while electricity for lighting purposes has1 to say the least1 not made any startling advances1 we have1 besides the regenerative lamps before mentioned1 the new ,welsbach light1 which is exhibited before you to-day1 by the kindness of ,dr4 ,wallace2 and if the results said to be obtained by it are at all what they are represented to be1 we certainly have a new departure in gas lighting of no mean order4 ,dr4 ,wallace--a gentleman who is well known to us as one well qualified to test its merits--has found that the ,welsbach burner produces a light equal to more than #i candles per cubic foot of gas of #be candle power1 thus nearly doubling the amount of light compared with gas consumed in the ordinary way4 ,the construction and manufacture of the burner ,i have seen described in these terms3 ,chemists have been diligently working for many years on the problem of how to convert into light the highly condensed heat of the ,bunsen burner2 and a ,vienna chemist now claims to have solved it4 ,the first condition of the problem was to find a medium on which the heat could be perfectly concentrated and raised to illuminating power4 ,many experiments have been made with platinum in a ,bunsen flame1 and a brilliant enough light has been produced1 but at a cost altogether outside commercial use4 ,the ,vienna chemist1 ,dr4 ,welsbach1 has discovered a composition which is as good a non-conductor--that is to say concentrator--of heat as platinum1 is much more durable1 and a great deal cheaper4 ,the base of it is a peculiar clay1 found in ,ceylon1 which combines the indestructibility of asbestos with the non-conducting property of platinum2 and having found the incandescent medium1 he has next adapted it to the ,bunsen burner4 ,in this arrangement there is the simplicity of genius4 ,he gets a fine cotton fabric woven into the shape of a cylinder1 with a tapering point4 ,in its first stage it is about #b inches in diameter2 and after being coated with the composition1 it is subjected to a strong heat4 ,this has two effects--first1 the cotton fiber is completely burned out1 while the composition retains the shape of the woven surface on which it was moulded4 ,then the cylinder contracts and solidifies until it becomes about the size of the forefinger of a glove4 ,dr4 ,welsbach calls this his mantle2 and by a simple arrangement he fits it on a ,bunsen burner1 and places an ordinary lamp chimney over it4 ,when the flame is applied1 the mantle becomes incandescent1 and gives out a brilliant yellow light1 which1 it may be said without exaggeration1 will compare favorably with any electric light yet put on the market4 ,for decorative effect a pretty frosted globe is used2 and by varying the globe a pure white or a pure yellow may be obtained4 ,it is also added that there is no act of ,parliament required for it1 nor even a provisional order of the ,board of ,trade4 ,no streets have to be broken up in order to lay down pipes2 and no wires have to be hung across the roofs of protesting householders4 ,the whole apparatus can be got ready to fit on an ordinary gas bracket2 and two or three spare frames with mantles can be kept in the house in case of accident4 ,whoever sees the ,welsbach incandescent light in operation will readily admit that it is the coming light4 ,it has beauty1 brilliancy1 purity1 and economy all on its side4 ,let us hope 7added the chairman7 this description is not overdrawn2 but of this you will later on have an opportunity of judging for yourselves4 ,no doubt the general or even partial adoption of this light would have a tendency to reduce the consumption of gas1 as a smaller quantity would be required to produce the same amount of illumination4 ,nevertheless1 gas engineers will hail it with approval if it in any way tends to popularize the use of gas1 and helps to increase the comfort and improve the sanitation of our houses1 churches1 halls1 etc4 ,moreover1 gas is continually being adopted for fresh purposes2 and we can confidently look forward to an almost unlimited field in the rapid and ever increasing use of gas as a fuel and for cooking purposes1 as well as for motive power4 ,the new and really excellent gas engines now being brought into the market will1 no doubt1 create a healthy rivalry1 and tend to cheapen these useful machines1 and so bring them within the reach of many persons who have hitherto been prevented from employing them by their considerable first cost4 ,,paraffin ,,as ,a ,,rival ,,of ,,coal ,,gas4 ,but while the day has gone by when any one of us fears the electric light as a possible rival1 we are not insensible to the fact that paraffin oil1 from its present low-price1 is a rival which we cannot afford to despise4 ,and more especially is this the case in many of the smaller towns and villages1 where the charge for gas is of necessity higher than in the larger towns4 ,doubtless1 with oil there is not the same cleanliness as with gas2 while there is also more trouble1 attention1 and considerable danger attending its use4 ,still1 in these hard times1 most people are inclined to adopt the cheapest article1 even at the cost of these drawbacks1 so as to make their money go as far as possible4 ,but not only as an illuminant is it being brought into direct competition with gas1 but also as a fuel and for cooking purposes1 as well as for motive power4 ,and ,i am inclined to think that the sooner we set about trying to solve the problem of how to meet this new competitor1 the better4 ,,oil ,,in ,,gas ,,making4 ,a new departure has also recently taken place in the adoption of oil for gas making purposes4 ,this1 of course1 is more fraught with danger to the coal master than to gas companies1 inasmuch as1 should this prove to be a more economical raw material from which to produce illuminating gas than coal1 our present coal gas works could be easily remodeled and turned into oil gas works4 ,this process has recently been introduced into a village in ,fifeshire4 ,and ,i have made it a point to visit and inspect the works1 which have been converted into an oil gas works1 so that ,i might be able to lay a few particulars before you4 ,the process1 however1 has not been in operation long enough to enable me to give you much information on the subject1 especially in the way of details of cost1 working expenses1 or permanency of the gas under varying and low temperatures4 ,the patentees claim that they can produce #ajj cubic feet of #fj candle gas from a gallon of oil1 or at a cost of #cs4 #aa;d4 per #a1jjj cubic feet for oil1 fuel1 and labor2 no more expense being incurred1 as the gas does not require purification4 ,at ,colinsburgh 7the village alluded to71 ,i was informed that the man sent by the patentees could produce #ajj cubic feet of gas per gallon of oil2 but they had no means of testing the illuminating power4 ,the gas company's own servant1 however1 only produced #hj cubic feet per gallon1 which they attributed to his want of experience in knowing the proper heat at which to work the retorts4 ,whether or not this was so ,i cannot tell2 but of this ,i am certain1 that the statement made that the gas does not require purification will not bear investigation4 ,when ,i tested it for sulphureted hydrogen and for ammonia1 both were indicated in such an unmistakable manner as none of us would care to see in our coal gas as sent out to the consumer4 ,,prices ,,of ,,residual ,,products4 ,what is of far more real consequence to us than the possible change from coal gas to oil gas1 however1 as long as we remain manufacturers of the former1 is the value of our residual products1 which has suffered so great and sudden a decline in value1 for which various remedies have been proposed1 though none of them1 ,i regret to say1 have as yet restored anything like the former value4 ,a statement of the highest prices realized for coal tar products1 and a comparison with those obtained on the #cjth of ,march last year and at the same time this year1 may not be uninteresting3 ---------------------------------------- ---------------------------- ,highest ,price on ,price on ,price ,march #cj1 ,march #cj1 #ahhf #ahhg ---------------------------------------- ---- per gal4 per gal4 per gal4 ---------------------------------------- - s4 d4 s4 d4 s4 d4 -------------------------------------- ,crude naphtha #j #d #j #j #j #d #j #j #h ,benzol 7#ij per cent47 #j #ae #j #j #a #d #j #b #f ,solvent naphtha #j #b #f #j #a #j #j #a #b ,burning naphtha #j #a #g #j #j #aj #j #j #aj ,creosote oil #j #j #c #j #j #j #j #j #a per ton4 per ton4 per ton4 -------------------------------------- s4 d4 s4 d4 s4 d4 -------------------------------------- ,pitch #a #ad #j #j #ae #j #j #ab #f ,sulphate of ammonia #ba #e #j #ac #aj #j #aa #aj #j ---------------------------------------- ---------------------------- ,this shows a great fall in value from highest to lowest1 which seems to have been touched last year1 except in the case of pitch and sulphate of ammonia1 both of which have marked a considerable decline1 even since last year1 but it is pleasing to note that the others have shown at least some slight improvement--crude naphtha and benzol having during the year risen nearly one hundred per cent4 in value4 ,let us hope that this is the precursor of a general rise in value from which we shall all profit4 ,for the purpose of bringing about this much desired end1 ,i understand that some of the gentlemen present to-day have been burning their tar in the retort furnaces1 and as it will be interesting to know what success they have attained1 ,i hope some of them will favor us with their experience on this subject4 ,in conclusion1 let me express the hope that the time is not far distant when the general trade of the country will attain to its wonted prosperity1 by which every branch of industry will benefit--ours among the number2 and that the hard times we have experienced1 now for a considerable number of years1 may not again return4 ,discussion next took place regarding the ,welsbach incandescence gas light1 which was opened by ,mr4 ,mc,grilchrist1 who remarked on the very fragile and tender nature of the mantle1 and expressed a hope that in this direction improvement might be looked for4 ,it was certainly a beautiful light1 and as to its consumption1 he stated that the lamp then shown to the meeting was only burning two cubic feet of gas per hour4 ,a voice3 ,two and two-tenths4 ,he felt satisfied that it would enable the manufacturers of gas to compete with paraffin oil1 so that with ,glasgow gas they could have such a light as they saw at the rate of #d;d4 for about fifty hours4 ,mr4 ,w4 ,key 7,tradeston ,gas ,works7 made a statement giving the results of inquiries he had made at ,st4 ,enoch ,station ,hotel1 where the light has for some time been on exhibition4 ,from the answers given to his inquiries he spoke rather disparagingly of the lamp1 but chiefly on account of the expense involved in renewing the mantles and the glass chimneys4 ,he admitted1 however1 that the lamps which he had seen were placed very unfavorably1 being exposed to the action of somewhat violent draughts1 and he subsequently remarked that the lamp was of such a nature as to effect the complete combustion of the carbon contained in the gas4 ,the burner must1 therefore1 be regarded as a great boon--as the burner1 in short4 ,mr4 ,d4,m4 ,nelson 7,glasgow7 gave his experience gained in connection with the light1 remarking that one of the great drawbacks to it was the very great rarity of the mineral from which the zirconium was obtained4 ,so scarce was it that it would become dearer than platinum and more valuable than gold if the lamp came into general use4 ,the light which the lamp gave out1 though it possessed intensity1 was deficient in diffusibility as compared with that given out from ordinary flat flame gas burners1 and this was another objection to it4 ,he argued at some length against the financial aspects of the scheme which was being promoted to buy up the ,welsbach patents1 and to introduce the lamp into this country4 ,his advice to his friends was not to have anything to do with the ,welsbach company1 and1 as investors1 to be very careful in accepting all the statements made about the light1 which he predicted would not be a financial success4 ,mr4 ,mc,crae was strongly opposed to any discussion being raised in regard to the question being considered in its financial aspects4 ,they1 as gas engineers1 did not require to trouble themselves with the doings of investors4 ,he regarded the ,welsbach burner as an improved appliance for consuming gas4 ,it was an invention which was quite new to him1 and as he was not in possession of any facts which would enable him to condemn it1 he thought they ought1 at least1 to give it a fair trial4 ,referring to the fragile nature of the mantle1 he remarked that there were minds at work aiming at giving a purer and more brilliant light from gas1 and so far he was of opinion that the light before them was a success4 ,his opinion as to the diffusibility of the light emitted from the burner differed from that of ,mr4 ,nelson1 as he considered the light possessed that quality in a high degree4 ,he had no doubt that the minds already at work on the incandescent light would seek out means for improving the burner4 99 99 99 99 99 ,to varnish chromos1 take equal quantities of linseed oil and oil of turpentine2 thicken by exposure to the sun and air until it becomes resinous and half evaporated2 then add a portion of melted beeswax4 ,varnishing pictures should always be performed in fair weather1 and out of any current of cold or damp air4 99 99 99 99 99 ,,the ,,new ,,british ,,coinage ,,and ,,jubilee ,,medal4 ,an important addition will be made to the coins now in circulation by the issue of the double florin1 the design of which is shown in one of our engravings4 ,the reverse is composed of crowned shields1 bearing the arms of the ,united ,kingdom arranged in the form of a cross between scepters1 a device which was first adopted for coins of ,charles ,,ii4 ,it was designed by ,thomas ,simon1 the greatest of all ,english engravers1 and it remains to be seen whether this handsome coin will be generally popular4 ,the reverse of the florin will for the future bear the same design4 ,during the past year her majesty was pleased to signify her pleasure that a portrait medallion1 by ,mr4 ,j4,e4 ,boehm1 ,r4,a41 modeled from life1 should be substituted for the effigy which the coins have hitherto borne4 ,in the new effigy1 her majesty appears crowned and veiled1 with the ribbon and star of the garter and the ,victoria and ,albert order4 ,the legend ,victoria ,dei ,gratia ,britanniarum ,regina1 ,fidei ,defensor is variously arranged on the different coins1 according to the exigencies of the design4 ,the opportunity has at the same time been taken1 with her majesty's approval1 for making certain alterations in the designs for the reverses of some of the coins by abandoning those which did not appear to possess sufficient artistic merit to warrant their retention4 ,the reverse of the sovereign will still bear the design of ,st4 ,george and the ,dragon1 by ,pistrucci1 first adopted for the sovereigns of ,george ,,iv41 and the reverses of the half-sovereign and threepence remain unchanged1 except that the crown has been assimilated to that used for the new effigy4 ,the ,st4 ,george and the ,dragon design will be resumed for the five-pound piece1 the double sovereign1 and the crown1 this design having been adopted for these pieces when originally struck4 ,the half-crown will bear the same reverse as that coin bore when first issued1 a design of considerable merit1 by ,merlin4 ,during the last half century public taste appears to have been satisfied1 both in this country and abroad1 with some such insignificant design as a wreath surrounding words or figures indicating the value of the coin2 and the shilling and sixpence have1 during the present reign1 been examples of this treatment4 ,they will in future1 like the half-crown1 bear the royal arms1 crowned1 and surrounded by the garter4 ,the queen was further pleased to command that the fiftieth anniversary of her majesty's accession should be commemorated by the issue of a medal4 ,the effigy for this medal1 which is also from a medallion by ,mr4 ,boehm1 has a somewhat more ornate veil than that on the coin2 and on the bust1 in addition to the ,victoria and ,albert order1 is shown the badge of the imperial order of the crown of ,india4 ,the reverse is a beautiful work by ,sir ,frederic ,leighton1 ,president of the ,royal ,academy1 of which the following is a description3 ,in the center a figure representing the ,british empire sits enthroned1 resting one hand on the sword of justice1 and holding in the other the symbol of victorious rule4 ,a lion is seen on each side of the throne4 ,at the feet of the seated figure lies ,mercury1 the ,god of ,commerce1 the mainstay of our imperial strength1 holding up in one hand a cup heaped with gold4 ,opposite to him sits the ,genius of ,electricity and ,steam4 ,below1 again1 five shields1 banded together1 bear the names of the five parts of the globe1 ,europe1 ,asia1 ,africa1 ,america1 and ,australasia1 over which the empire extends4 ,on each side of the figure of ,empire stand the personified elements of its greatness--on the right 7of the spectator71 ,industry and ,agriculture2 on the left1 ,science1 ,letters1 and ,art4 ,above1 the occasion of the celebration commemorated is expressed by two winged figures representing the year #ahhg 7the advancing figure7 and the year #ahcg 7with averted head71 holding each a wreath4 ,where these wreaths interlock1 the letters ,v4,r4,i4 appear1 and1 over all1 the words ',in ,commemoration4' ,the issue of both the new coins and the medal began on ,june #ba1 the day appointed for the celebration of her majesty's jubilee4--,illustrated ,london ,news4 ,illustration3 ,,the ,,new ,,british ,,coinage ,,and ,,jubilee ,,medal4 #a4 ,half ,crown4 #b and #c4 ,double ,florin1 reverse and obverse4 #d4 ,double ,sovereign4 #e4 ,shilling4 #f4 ,sixpence4 #g and #h4 ,jubilee ,medal4 99 99 99 99 99 ,,bricks ,,and ,,brickwork4 ,footnote3 ,a recent lecture delivered at ,carpenters' ,hall1 ,london ,wall1 ,e4,c4--,building ,news4 ,by ,professor ,t4 ,,roger ,,smith1 ,f4,r4,i4,b4,a4 ,timber1 stone1 earth1 are the three materials most used by the builder in all parts of the world4 ,where timber is very plentiful1 as in ,norway or ,switzerland1 it is freely used1 even though other materials are obtainable1 and seems to be preferred1 notwithstanding the risk of fire which attends its use4 ,where timber is scarce1 and stone can be had1 houses are built of stone4 ,where there is no timber and no stone1 they are built of earth--sometimes in its natural state1 sometimes made into bricks and sun-dried1 but more often made into bricks and burned4 ,london is one of the places that occupies a spot which has long ceased to yield timber1 and yields no stone1 so we fall back on earth--burnt into the form of bricks4 ,brick was employed in remote antiquity4 ,the ,egyptians1 who were great and skillful builders1 used it sometimes2 and as we know from the book of ,exodus1 they employed the forced labor of the captives or tributaries whom they had in their power in the hard task of brick making2 and some of their brick-built granaries and stores have been recently discovered near the site of the battle of ,tel-el-,kebir4 ,the ,assyrians and ,babylonians made almost exclusive use of brickwork in erecting the vast piles of buildings the shapeless ruins of which mark the site of ancient ,nineveh and of the cities of the valley of the ,euphrates4 ,their bricks1 it is believed1 were entirely sun-dried1 not burnt to fuse or vitrify them as ours are1 and they have consequently crumbled into mere mounds4 ,the ,assyrians also used fine clay tablets1 baked in the fire--in fact1 a kind of terra cotta--for the purpose of records1 covering these tablets with beautifully executed inscriptions1 made with a pointed instrument while the clay was soft1 and rendered permanent by burning4 ,we don't know much about ,greek brickwork2 but it is probable that very little brick1 if any1 was made or used in any part of ,greece1 as stone1 marble1 and timber abound there2 but the ,romans made bricks everywhere1 and used them constantly4 ,they were fond of mixing two or more materials together1 as for example building walls in concrete and inserting brickwork at intervals in horizontal layers to act as courses of bond4 ,they also erected buildings of which the walls were wholly of brick4 ,they turned arches of wide span in brickwork2 and they frequently laid in their walls at regular distances apart courses of brick on edge and courses of sloping bricks1 to which antiquaries have given the name of herring-bone work4 ,the ,roman bricks are interesting as records1 for it was customary to employ the soldiers on brick making1 and to stamp the bricks with names and dates2 and thus the ,roman bricks found in this country give us some information as to the military commanders and legions occupying different parts of ,england at different periods4 ,flue bricks1 for the passage of smoke under floors and in other situations1 are sometimes found4 ,the ,roman brick was often flat and large--in fact1 more like our common paving tiles1 known as foot tiles1 only of larger size than like the bricks that we use4 ,they vary1 however1 in size1 shape1 and thickness4 ,not a few of them are triangular in shape1 and these are mostly employed as a sort of facing to concrete work1 the point of the triangle being embedded in the concrete and the broad base appearing outside4 ,after the ,roman time1 brick making seems to have almost ceased in ,england for many centuries4 ,it is true we find remains of a certain number of massive brick buildings erected not long after the ,norman conquest2 but on examination it turns out that these were put up at places where there had been a ,roman town1 and were built of ,roman bricks obtained by pulling down previous buildings4 ,the oldest parts of ,st4 ,albans ,abbey and portions of the old ,norman buildings at ,colchester are examples of this sort4 ,apparently1 timber was used in this country almost exclusively for humble buildings down to the #afth century4 ,this is not surprising1 considering how well wooded ,england was2 but stone served during the same period for important buildings almost to the exclusion of brick4 ,this is more remarkable1 as we find stone churches and the ruins of stone castles in not a few spots remote from stone quarries1 and to which the stone must have been laboriously conveyed at a time when roads were very bad and wheel carts were scarce4 ,about the time of the ,tudors1 say the reign of ,queen ,elizabeth1 the making of bricks was resumed in ,england1 and many dwelling houses and some few churches were built of good brickwork in that and succeeding reigns4 ,we find in such buildings as ,hampton ,court ,palace1 ,st4 ,james' ,palace1 and ,chelsea ,hospital examples of the use of brickwork in important buildings near ,london at later dates4 ,the fire of ,london1 in #afff1 gave a sudden check to the use of timber in house building in the metropolis4 ,previous to that date the majority of houses had been of a sort the most ornamental examples of which were copied in ,old ,london at the ,colonial ,exhibition4 ,the rebuilding after the fire was largely in brick2 and in the suburbs1 in the latter part of the #agth and the #ahth centuries1 many dignified square brick mansions1 with bold1 overhanging eaves and high roofs and carved ornaments1 entered through a pair of florid wrought iron high gates1 were built1 some few of which still linger in ,hampstead and other suburbs4 ,the war time at the beginning of this century was a trying time for builders1 with its high prices and heavy taxes1 and some of the good-looking brick buildings of that day turn out to have been very badly built when they are pulled about for alterations4 ,with the rapid1 wonderful increase in population and wealth in this metropolis during the last #ej years a vast consumption of bricks has taken place1 and a year or two back it was reported by the commissioners of police that the extensions of ,london equaled in a year #gj miles of new house property1 practically all of brick4 ,brick were heavily taxed in the war time which ,i have referred to1 and the tax was levied before burning4 ,there was a maximum size for the raw brick1 which it was supposed served to keep bricks uniform1 and the expectation was entertained that when the duty came off1 many fancy sizes of bricks would be used4 ,this has not1 however1 turned out to be the case4 ,the duty has been taken off for years2 but the differences in the size of bricks in ,england are little more than what is due to the different rate of shrinkage of brick earth under burning4 ,it must not1 however1 be supposed that they have always1 and in all countries1 been of about the same dimensions4 ,the size and proportions of bricks have varied extremely in different countries and in the same country at different periods4 ,some bricks of unusual shapes have also been employed from time to time4 ,other countries besides ,england possess districts which from various circumstances have been more or less densely built on1 but do not yield much stone or timber2 and1 accordingly1 brickwork is to be met with in many localities4 ,holland and ,belgium1 for example1 are countries of this sort2 and the old connection between ,holland and ,england led to the introduction among us1 in the reign of ,william ,,iii41 of the ,dutch style of building1 which has been in our own day revived under the rather incorrect title of ,queen ,anne architecture4 ,another great brick district exists on the plains of ,lombardy and the northern part of ,italy generally1 and beautiful brickwork1 often with enrichments in marble1 is to be found in such cities as ,milan1 ,pavia1 ,cremona1 and ,bologna4 ,many cities and towns in ,northern ,germany are also brick built1 and furnish good examples of the successful treatment of the material4 ,in some of these ,german buildings1 indeed1 very difficult pieces of construction1 such as we are in the habit of thinking can only be executed in stone1 are successfully attempted in brick4 ,for example1 they execute large tracery windows in this material4 ,great brick gables1 often with the stepped outline known as crows' feet1 are an excellent architectural feature of these ,german brick-built towns4 ,in parts of ,france1 also1 ornamental brickwork was from time to time made use of1 but not extensively4 ,it is not necessary to go very minutely into the manufacture of bricks2 but perhaps ,i ought to say a word or two on the subject4 ,good brick earth is not simple clay1 but a compound substance2 and what is essential is that it should burn hard or1 in other words1 partly vitrify under the action of heat4 ,the brick earth is usually dug up in the autumn1 left for the frosts of winter to break it up1 and worked up in the early spring4 ,the moulding is to a very large extent done by hand1 sometimes in a wet mould1 sometimes in a dry sanded mould1 and the bricks are first air-dried1 often under some slight shelter1 as the rain or frost damages them when fresh made2 and then1 when this process has made them solid enough to handle1 they are burned1 and sorted into qualities4 ,the ordinary or stock brick of ,london and the neighborhood presents a peculiarity the origin of which is not known1 and which is not met with1 so far as ,i know1 in other parts4 ,very fine coal or cinders is mixed with the brick earth1 and when the bricks are fired these minute particles of fuel scattered through the material all of them burn1 and serve to bake the heart of the brick4 ,stock bricks are burnt in a clamp made of the raw bricks themselves with layers of fuel1 and erected on earth slightly scooped out near the middle1 so that as the bricks shrink they drop together1 and do not fall over sideways4 ,most other varieties of bricks are kiln burnt4 ,a very large number of inventions for making bricks by machinery have been patented4 ,if you have occasion to look through the specifications of these patents1 you will find four or five main ideas appearing and reappearing1 and only here and there an invention which is to some extent different from the others4 ,a great majority of these inventions include machinery for preparing the clay or brick earth1 so that it may be dug up and filled into a receptacle and worked up1 screened from pebbles1 and made fit for use in a short time1 so as not to have to wait a whole winter4 ,this is done in some sort of pug mill4 ,a pug mill is a machine consisting of a large cylinder with a central shaft passing through it from top to bottom4 ,knives or blades are arranged spirally on the shaft1 and other blades project into the interior of the cylinder from the walls of it4 ,the material1 after being screened1 is fed into this at the top1 and properly moistened4 ,the shaft is caused to rotate1 and the blades divide and subdivide the material1 forcing it always downward1 so that it at last escapes at the bottom of the pug mill in a continuous stream of moist1 well worked up clay1 issuing with some force4 ,in one type of machine this clay stream is forced through a square orifice1 from which it comes out of the section of a brick1 and by a knife or wire or some other means it is cut into lengths4 ,in another type of machine there is a large revolving drum working on a horizontal axis1 with open moulds all round its edge4 ,the clay enters these moulds1 and there is an arrangement of plungers by which it is first compressed within the mould and then forced out on to an endless band or some other contrivance that receives it4 ,a third type of machine has the moulds in the flat top of a revolving table1 which1 as it turns1 carries each mould in succession first to a part where it is filled from the pug mill1 next to where its contents are compressed1 and lastly to where they are pushed out for removal4 ,however made1 the brick1 when moulded1 dried1 and burnt1 and ready for market1 belongs to some one sort1 and is distinguished from other sorts by its size1 color1 quality1 and peculiarities4 ,the sorts of brick that are to be met with in the ,london market are very varied4 ,to enumerate them all would make a tedious list2 to describe them all would be equally tedious4 ,i will endeavor1 however1 to give some idea of the most conspicuous of them4 ,we will begin with that family of bricks of which the ,london stock brick is the type4 ,it has been said these are clamp burnt1 and almost all the internal brickwork--and not a little of the external--of the metropolis is of stock brickwork4 ,a good ,london stock brick is an excellent brick for general purposes1 but cannot be called beautiful4 ,considering the vast quantity of brickwork done in the metropolis1 it is a matter for congratulation that such sound materials as good stock bricks1 stone lime1 and ,thames sand are so easily procurable1 and can be had at a price that puts them within the reach of all respectable builders4 ,when a clamp has been burnt its contents are found to have been unequally fired1 and are part of them underburnt1 part well burnt1 part overburnt4 ,they are sorted accordingly into shuffs1 grizzles1 stocks of two or three qualities1 shippers1 and burrs4 ,several sorts of malm stocks1 which are superior in color and texture1 are made1 and are used for facing bricks and for cutting2 and what are called paviors1 which are dark and strong bricks1 are also made4 ,the ,london stock is erroneously1 but usually1 described as gray4 ,it is really of a pie crust yellow of various tones4 ,sometimes it is the same color when cut1 but the hardest stocks are of a dark1 dirty purple or brown1 or sometimes nearly black inside4 ,a stock brick is rarely quite square or quite true2 its surface is often disfigured by black specks and small pits1 and a stack of them often looks uninviting2 yet a skillful bricklayer1 by throwing out the worst1 by placing those of bad colors or much out of shape in the heart of the wall1 and by bringing to the front the best end or side of those bricks which form part of the face1 can always make the bricks in his work look far better than in the stack4 ,another important group is the group of ,suffolk and ,norfolk bricks1 red and white4 ,these are very largely employed as facing bricks and for arches and cut mouldings4 ,moulded bricks are also to a large extent made of the same material4 ,these bricks are brought to ,london in large quantities4 ,they have a sanded face1 are mostly square1 true1 and of uniform color1 but they are usually porous1 soft1 and absorbent4 ,still1 they are in great demand as facing bricks1 and the moulded bricks enable the architect to produce many architectural effects at a moderate outlay4 ,these fields furnish many sorts of bricks1 which are called rubbers1 and which are employed 7as malm stocks also are7 for arches of the more elaborate sort1 where each brick is cut to its shape and rubbed true1 and for mouldings1 and even sometimes for carving4 ,mouldings that are formed by cutting the bricks can be got more perfectly true than when moulded bricks are used2 but the expense is greater1 and when it is done the material is less durable1 for the softer sorts of brick are naturally used for cutting1 and the moulded face is less sound than the original burnt face of any brick4 ,red bricks are to some extent made in fields within easy reach of ,london2 but the best come from some distance4 ,red ,suffolk bricks have been alluded to4 ,there is a considerable importation of red ,fareham bricks1 brought all the way from the vicinity of ,portsmouth2 these are good both in quality and color4 ,good red bricks are also now made at ,ascot1 and are being used to a considerable extent in the metropolis4 ,a strawberry-colored brick from ,luton has been extensively used at ,hampstead4 ,it is hard1 and of a color which contrasts well with stone1 but not very pleasing used alone4 ,glazed bricks of all colors are obtainable4 ,they are usually very hard and square1 and the use of them where an impervious glazed face is required1 as1 for example1 in a good stable1 is better than the employment of glazed tiles1 in the employment of which there is always a possibility of part of the lining becoming loose or falling off4 ,there is a difficulty in obtaining a large quantity 7of some colors1 at least7 exactly uniform in tint4 ,bricks with a very hard face1 but not glazed1 are obtainable4 ,what is called a washing brick is now made in various colors1 adapted for the lining of interiors1 and there are hard bricks of a very pale straw color1 known as ,beart's patent bricks1 made1 ,i believe1 of gault clay1 which were some years ago bought up by the ,great ,northern ,railway in large numbers4 ,these bricks have the peculiarity of being pierced with holes about in4 in diameter1 passing quite through the brick1 and they are extremely hard1 partly because these holes permit the hot air and smoke in the kiln to approach very near to the interior of the brick4 ,i am of opinion that the glazed or dull qualities of hard bricks might with great advantage be often introduced into ,london streets4 ,what we want is something that will wash4 ,the rough surface of stocks or ,suffolk facing bricks catches the black in the ,london atmosphere and gradually gets dark and dull4 ,a perfectly hard face is washed clean by every shower4 ,a good many years ago ,i built a warehouse with stock bricks1 and formed the arches1 strings1 etc41 of bricks with a very hard face1 and1 as ,i expected1 the effect of time has been to make these features stand out far better than when they were fresh2 in fact1 the only question is whether they have not now become too conspicuous4 ,to return to the bricks in the ,london market3 we have firebricks made of fireclay1 and almost vitrified and capable of standing intense heat4 ,these are used for lining furnaces1 ovens1 flues1 etc4 ,then we have almost1 if not quite1 as refractory a material in ,staffordshire blue bricks1 used--in various forms--for paving channels1 jambs of archways1 etc4 ,there are also small bricks called clinkers1 chiefly used for stable paving4 ,dutch clinkers1 formerly imported largely from ,holland1 were small1 rough bricks1 laid on edge1 and affording a good foothold for the horse4 ,adamantine clinkers1 made of gault clay1 are much used2 they must have chamfered edges1 otherwise they make too smooth a floor for a stable4 ,many other varieties are obtainable in ,london1 and are more or less used1 but these are the most prominent4 ,in many parts of ,england special varieties of brick are to be found1 and every here and there one falls upon a good brickmaker who is able to produce good moulded or embossed or ornamental bricks1 such as those which have been supplied to me years ago by ,mr4 ,gunton1 and more recently by ,mr4 ,brown1 both of ,norwich1 or by ,mr4 ,cooper1 of ,maidenhead4 ,it is of importance to those whose business it is to look after or engage in building operations1 that they should early learn what to look out for in each material4 ,of course1 a man only becomes a judge of bricks1 or timber1 or stone by experience2 but he is far better able to take the benefit of experience when it comes to him if he knows from the first to what points to direct attention4 ,wherefore ,i make no apology for trying to put before you the points of a good brick1 and in doing so ,i shall partly quote from a memorandum published now a good many years ago by the ,manchester ,society of ,architects4 ,a good brick is uniform in size2 standard1 #i by #d by #b in42 weight about #g lb4 each #aaj lb4 per foot cube2 is rectangular1 true faced1 but only one end and one side need be smooth2 has no print sinking on either face1 but a hollow on one or both beds4 ,when saturated with water1 a brick should not absorb more than #bj per cent1 of its own weight of water1 should absorb it reluctantly1 and part with it freely at ordinary temperatures4 ,it should be uniformly burnt1 should be sound1 free from cracks1 flaws1 stones1 lumps of any kind1 but especially lumps of lime1 should be of a good color for its sort 7whether red1 yellow1 or white71 should have a metallic clang when two bricks are struck together2 when broken should be sound right through1 should be tough and pasty in texture1 not granular1 and should require repeated blows to break it1 rather than one hard blow 7such bricks will withstand cartage and handling best74 ,so much for bricks4 ,to make brickwork1 however1 another ingredient is required--namely1 mortar or cement4 ,all mortars and1 in fact1 all the cementing materials used 7except bituminous ones7 in bricklaying have lime as their base1 and depend upon the setting quality of quicklime1 which has to be mixed with sand or some suitable substitute for it1 to make mortars4 ,limes and cements are far too wide a subject to be dealt with as part of an evening's lecture on another topic1 and no doubt they will hereafter form the subject of a lecture or lectures4 ,to-night ,i propose only to remind you that there are such substances as these1 and that they possess certain qualities and are obtainable and available for the bricklayer's purposes1 without attempting an investigation into the chemistry of cements1 or their manufacture1 etc4 ,ordinarily1 brickwork may be divided into brickwork in mortar and in cement2 but there are many qualities of mortar and several sorts of cement4 ,mortar made with what are called fat or rich limes--that is to say1 nearly pure lime1 such as is got by calcining marble or pure chalk--sets slowly1 with difficulty1 and is rarely tenacious4 ,burnt clay or brick reduced to powder improves the setting of such lime1 especially if the two materials be calcined together2 so will an admixture of cement4 ,mortar made with what is known as slightly hydraulic lime1 that is to say1 lime containing a small proportion of clay1 such as the gray stone lime of ,dorking1 ,merstham1 and that neighborhood1 sets well1 and is tenacious and strong4 ,mortar made with hydraulic lime1 that is to say1 lime with a considerable admixture of clay1 such as the lias lime1 sets under water or in contact with wet earth4 ,it is best to use this lime ground to powder1 and not to mix so much sand with it as is used with stone lime4 ,a sort of mortar called selenitic mortar1 the invention of the late ,general ,scott1 has been made use of in many of the buildings of the ,school ,board for ,london1 and was first employed on a large scale in the erection of the ,albert ,hall4 ,the peculiarity consists in the addition of a small dose of plaster of ,paris 7sulphate of lime7 very carefully introduced and intimately mixed4 ,the result is that the mortar so made sets rapidly1 and is very hard4 ,it is claimed that a larger proportion of sand can be used with selenitic lime than with ordinary1 thus counterbalancing the extra expense occasioned by royalty under the patent and special care in mixing4 ,when a limestone contains #bj to #dj per cent1 of clay1 it becomes what is called a cement1 and its behavior is different from that of limestones with less clay4 ,ordinary limestones are1 as you know1 calcined in a kiln4 ,the material which comes from the kiln is called quicklime1 and1 on being dosed with water1 it slakes1 and crumbles to powder1 and in the state of slaked lime is mixed up with mortar4 ,cement stones are also calcined2 but the resulting material will not fall to pieces or slake under water4 ,it must be ground very fine1 and when moistened sets rapidly1 and as well under water as in air1 and becomes very hard and is very tenacious4 ,brickwork in mortar will always settle and compress to some extent4 ,not so brickwork in cement1 which occasionally expands1 but is never to be compressed4 ,this quality and the rapid setting1 tenacity1 and strength of brickwork in cement make it a most valuable material to use in those buildings or parts of a building where great steadiness and strength are wanted1 and in sewage and dock work1 where there is water to contend with4 ,a good many cements made from natural stones used to be employed1 such as ,medina1 ,harwich1 ,atkinson's1 or ,roman cement4 ,the last named is the only one which is now much employed1 except locally4 ,it has the quality of setting with exceptional rapidity1 and is on that account sometimes the best material to employ2 but for almost every purpose the artificial compound known as ,portland cement is preferable4 ,portland cement is made largely near ,rochester4 ,its materials are simple and cheap4 ,they may1 without much departure from the truth1 be said to be ,thames mud and chalk2 but the process of manufacture requires care and thoroughness4 ,the article supplied1 when of the best quality1 has great strength1 and is quick setting1 and is far better than what was manufactured from stones in which the ingredients existed in a state of nature4 ,in ,england we slake our lime and make use of it while it is fresh2 but it may interest you to know that the custom in ,italy and parts of ,france is different4 ,there it is customary to slake the lime long before it is wanted1 and to deposit it in a pit and cover it up with earth4 ,in this condition it is left for months--,i believe in ,italy for a year--and when taken out it is stiff1 but still a pasty substance4 ,it is beaten1 and more water added1 and it is then made into mortar with sand4 ,it is claimed for mortar made in this way that is exceptionally strong4 ,now that we have considered bricks and partly considered mortar1 it remains to pay some attention to brickwork4 ,the simplest and most familiar work for a bricklayer to do is to build a wall4 ,in doing this his object should be to make it as stout as possible for the thickness1 and this stoutness can only be obtained by interlacing the bricks4 ,if they were simply laid on the top of each other1 the wall would be no more than a row of disconnected piles of bricks liable to tumble down4 ,when the whole is so adjusted that throughout the entire wall the joints in one course shall rest on solid bricks and shall be covered by solid bricks again--in short1 when the whole shall break joint--then this wall is said to be properly bonded1 and has as much stability given to it as it can possibly possess4 ,there are two systems of bonding in use in ,london1 know as ,english bond and ,flemish bond4 ,english bond is the method which we find followed in ancient brickwork in this country4 ,in this system a course of bricks is laid across the wall1 showing their heads at the surface1 hence called headers1 and next above comes a course of bricks stretching lengthways at the wall1 called stretchers1 and so on alternately4 ,with the ,dutch fashions came in ,flemish bond1 in which1 in each course1 a header and a stretcher alternate4 ,in either case1 at the corners1 a quarter-brick called a closer has to be used in each alternate course to complete the breaking joint4 ,there is not much to choose between these methods where the walls are only one brick thick4 ,but where they are thicker the ,english has a decided advantage1 for in walls built in ,flemish bond of one and a half brick thickness or more there must be a few broken bricks1 or bats1 and there is a strong temptation to make use of many4 ,if this takes place1 the wall is unsound4 ,many of the failures of brickwork in ,london houses arise from the external walls1 where they are #a bricks thick1 being virtually in two skins2 the inner #i in4 does the whole of the work of supporting floors and roof1 and when it begins to fail1 the outer face bulges off like a large blister4 ,i have known cases where this had occurred1 and where there was no header brick for yards1 so that one could pass a #e ft4 rod into the space between the two skins and turn it about4 ,this is rather less easy to accomplish with ,english bond1 and there are other advantages in the use of that bond which make it decidedly preferable1 and it is now coming back into very general use4 ,there are some odd varieties of bond1 such as garden bond and chimney bond4 ,but of these ,i only wish to draw your attention to what is called cross bond4 ,the name is not quite a happy one4 ,diagonal bond is hardly better4 ,the thing itself is to be often met with on the ,continent1 and it is almost unknown here4 ,but it would be worth introducing1 as the effect of it is very good4 ,french cross bond1 otherwise diagonal bond 7liaison en croix71 is ,english bond1 but with the peculiarity that in every fourth course one header is made use of in the stretcher course at the quoin4 ,the result is that the stretchers break joint with each other1 and all the joints range themselves in diagonal lines1 and if in any part of the work headers of a different brick are introduced1 the appearance of a cross is at once brought out2 and even without this the diagonal arrangement of joints is very perceptible and pleasing4 ,besides wall building1 the bricklayer has many other works to perform4 ,he has to form fireplaces1 flues1 chimneys1 and the flat trimmer arches which support the hearth1 and has to set the stove1 kitchen range1 copper1 etc41 in a proper manner4 ,he has to form various ornamental features and much else1 some of which we shall have an opportunity of noticing rather later4 ,the strangest business1 however1 which is intrusted to the bricklayer is building downward--by the method known as underpinning--so that if a foundation has failed1 a sounder one at a greater depth may be reached2 or if a basement is required under an existing building which has none1 the space may be excavated and the new walls built so as to maintain the old4 ,this work has to be done with great caution1 and bit by bit1 and is usually left to experienced hands4 ,the mode in which the mortar joints of a brick wall are finished where they show on the external or internal face is a matter worth a moment's attention4 ,it is important that the joints of the work shall be so finished as to keep out wet and to be as durable as possible1 and it is desirable that they should improve1 or at any rate not disfigure1 the appearance of the work4 ,the method which architects strongly advocate is that the joints shall be struck as the work proceeds--that is1 that very shortly after a brick is laid1 and while the mortar is yet soft1 the bricklayer shall draw his trowel1 or a tool made for the purpose1 across it1 to give it a smooth and a sloping surface4 ,this is best when the joint is what is called a weather joint--i4e41 one in which the joint slopes outward4 ,sloping it inward is not good1 as it lets in wet2 finishing it with a hollow on the face is often practiced1 and is not bad4 ,bricklayers1 however1 most of them prefer that the mortar joints should be raked out and pointed--that is to say1 an inch or an inch and a half of the mortar next the outer face be scratched out and replaced with fresh mortar1 and finished to a line4 ,in cases where the brickwork is exposed to frost1 this proceeding cannot be avoided1 because the frost damages the external mortar of the joints4 ,but the bricklayers prefer it at all seasons of the year1 partly because brickwork is more quickly done if joints are not struck at the time2 partly because they can1 if they like1 wash the whole surface of the work with ocher1 or other color1 to improve the tint2 and partly because1 whether the washing is done or not1 it smartens up the appearance of the work4 ,the misfortune is that this pointing1 instead of being the edge of the same mortar that goes right through1 is only the edge of a narrow strip1 and does not hold on to the old undisturbed mortar1 and so is far less sound1 and far more liable to decay4 ,there is a system of improving the appearance of old1 decayed work by raking out and filling up the joint1 and then making a narrow mortar joint in the middle of this filling in1 and projecting from the face4 ,this is called tuck pointing4 ,it is very specious1 but it is not sound work4 ,brick arches are constantly being turned1 and of many sorts4 ,an arch consists of a series of wedge shaped blocks1 known as voussoirs1 arranged in a curve1 and so locking one another together that unless the abutments from which the arch springs give way1 it will not only carry itself1 but sustain a heavy load4 ,it is a constant practice to cut bricks to this shape and build them into an arch1 and these are sometimes cut and rubbed2 sometimes1 when the work is rougher1 they are axed4 ,but in order to save the labor of cutting1 arches are sometimes turned with the bricks left square1 and the joints wedge shaped4 ,in this case the rings should be only half a brick each1 so that the wedge need not be so very much wider at back than at face1 and they are set in cement1 as that material adheres so closely and sets so hard4 ,arches of two or more half-brick rings in cement are good construction1 and are also used for culvert work4 ,a less satisfactory sort of arch is what is called the flat arch4 ,here1 instead of being cambered as it ought to be1 the soffit is straight2 but the brickwork being deep1 there is room enough for a true arch that does the work1 and for useless material to hang from it4 ,these arches are generally rubbed or axed1 and are very common at the openings of ordinary windows4 ,but no one who has studied construction can look at them without a kind of wish for at least a slight rise1 were it only two inches4 ,sometimes when these straight arches are to be plastered over they are constructed in a very clumsy manner1 which is anything but sound1 and from time to time they give way4 ,the weight of brickwork1 of course1 varies with the weight of the individual bricks4 ,but stock brickwork in mortar weighs just about one hundred weight per cubic foot1 or #bj cubic feet to the ton4 ,in cement it is heavier1 about #abj lb4 to the cubic foot4 ,the strength of brickwork depends of course on the strength of the weakest material--i4e41 the mortar--though when it is in cement the strength of brickwork to withstand a weight probably approaches that of the individual bricks4 ,some experiments quoted in ,rivington's ,notes give the following as the crushing weight per foot--that is to say1 weight at which crushing began--of piers having a height of less than twelve times their diameter3 ,tons per foot4 ,best stocks1 set in ,portland cement and sand #a to #a1 and three months old4 #dj ,ordinary good stocks1 three months old4 #cj ,hard stocks1 ,roman cement and sand #a to #a1 three months old4 #bh ,hard stocks1 lias lime1 and sand #a to #b1 and six months old4 #bd ,hard stocks1 gray chalk lime1 and sand1 six months old4 #ab ,the rule given in popular handbook1 that brickwork in mortar should not have to carry more than three tons per superficial foot1 and in cement more than five tons1 is probably sound1 as in no building ought the load to approach the crushing point1 and1 indeed1 there are many sorts of foundations on which such a load as five tons per foot would be too great to be advisable4 ,it is a rather interesting inquiry1 whenever we are dealing with a building material1 if we ask what can we best do with it1 and for what is it ill fitted4 ,the purposes for which brick can be best used depend1 of course1 upon its qualities4 ,speaking generally1 such purposes are very numerous and very various1 especially the utilitarian purposes1 though rich and varied ornamental work can also be executed in brickwork4 ,perhaps the most remarkable quality of brickwork is that it can be thrown into almost any shape4 ,it is in this respect almost like a plastic material1 and this peculiarity it owes chiefly to the very small size of each brick as compared with the large masses of the brickwork of most buildings4 ,stone is far less easily dealt with than brick in this respect4 ,think for a moment of the great variety of walls1 footings1 piers1 pilasters1 openings1 recesses1 flues1 chimney breasts1 chimney shafts1 vaults1 arches1 domes1 fireproof floors1 corbels1 strings1 cappings1 panels1 cornices1 plinths1 and other features met with in constant use1 and all formed by the bricklayer with little trouble out of the one material--brickwork6 ,a little consideration will convince you that if the same material furnishes all these1 it must be very plastic4 ,as a limitation we ought to note that this almost plastic material cannot be suddenly and violently dealt with--that is to say1 with the exception of some sorts of arches1 you cannot form any abrupt or startling feature in brickwork1 and you are especially limited as to projections4 ,if you wish to throw out any bold projection1 you may support it on a long and sloping corbel of brickwork4 ,but if there is not room for that1 you must call in some other material1 and form the actual support in stone1 or terra cotta1 or iron1 and when you have gained your projection1 you may then go on in brickwork if you like4 ,brick cornices should be steep1 but cannot be bold1 and so with other ornamental and structural features4 ,a noteworthy property of brickwork1 and one of immense value1 is that it is thoroughly fireproof2 in fact1 almost the only perfectly fireproof material4 ,there is an interesting account of the great fire of ,london by one of the eye witnesses1 and among the striking phenomena of that awful time he notes that the few brick buildings which existed were the only ones able to withstand the raging fire when it reached them4 ,in our own day a striking proof of the same thing was given in the great fire in ,tooley street1 when ,braidwood lost his life4 ,i witnessed that conflagration for a time from ,london ,bridge1 and its fury was something not to be described4 ,there were vaults under some of the warehouses stored with inflammable materials1 the contents of which caught fire and burnt for a fortnight1 defying all attempts to put them out4 ,yet these very vaults1 though they were blazing furnaces for all that time1 were not materially injured4 ,when the warehouses came to be reinstated1 it was only found necessary to repair and repoint them a little1 and they were retained in use4 ,the fact is that the bricks have been calcined already1 so has the lime in the mortar1 and the sand is not affected by heat1 so there is nothing in brickwork to burn4 ,against each of these good qualities1 however1 we may set a corresponding defect4 ,if brickwork is easily thrown into any shape1 it is also easily thrown out of shape4 ,it has little coherence or stability1 less than masonry and very considerably less than timber4 ,if any unequal settlement in the foundation of a brick building occurs1 those long zigzag cracks with which we in ,london are only too familiar set themselves up at once2 and if any undue load1 or any variation in load1 exists1 the brickwork begins to bulge4 ,any serious shock may cause a building of ordinary brickwork to collapse altogether1 and from time to time a formidable accident occurs owing to this cause4 ,the fact is1 the bricks are each so small compared to the mass of the work1 and the tenacity or hold upon them of even fairly good lime mortar is so comparatively slight1 that there is really but little grip of one put upon another4 ,persons who have to design and construct brick buildings should never forget that they have to be handled with caution1 and are really very ticklish and unstable4 ,one or two of the methods of overcoming this to some extent may be mentioned4 ,the first is the introduction of what is called bond4 ,at the end of the last century it was usual to build in1 at every few feet in height1 bond timbers1 which were embedded in the heart of the walls4 ,if these had always remained indestructible1 they would no doubt have served their purpose to some extent4 ,unfortunately1 timber both rots and burns1 and this bond timber has brought down many a wall owing to its being destroyed by fire1 and has in other cases decayed away1 and caused cracks1 settlements1 and failures4 ,the more modern method of introducing a strong horizontal tie is to build into the wall a group of bands of thin iron1 such as some sorts of barrels are hooped with--hence called hoop iron4 ,the courses of bricks where this occurs must be laid in cement1 because iron in contact with cement does not perish as it does in contact with mortar4 ,if in every story of a building four or five courses are thus laid and fortified1 a great deal of strength is given to the structure4 ,another method1 which has rather fallen into disuse1 is grouting4 ,this is pouring liquid mortar1 about the consistency of gruel1 upon the work at about every fourth course4 ,the result is to fill up all interstices and cavities1 and to delay the drying of the mortar1 and brickwork so treated sets extremely hard4 ,i have seen a wall that had been so treated cut into1 and it was quite as easy to cut the bricks 7sound ones though they were7 as the mortar joints4 ,grouting is objected to because it interferes with the good look of the work1 as it is very difficult to prevent streaks of it from running down the face1 and it is apt to delay the work4 ,but it is a valuable means of obtaining strong brickwork4 ,another and a more popular method is to build the work in cement1 now usually ,portland cement4 ,this1 of course1 makes very strong1 sound work1 and does not involve any delay or dirt like grouting1 or the introduction of any fresh material like hoop iron4 ,but it1 of course1 adds to the expense of the work considerably1 as cement is much more costly than lime4 ,i ought to add that the advocates of ,scott's selenitic mortar claim that it not only sets quickly and hard1 but that it is extremely tenacious1 and consequently makes a much more robust wall than ordinary mortar4 ,i dare say this is true2 but ,i have not happened to see such a wall cut into1 and this is the best test of solidity4 ,the second deficiency in brickwork which ,i am bound to notice is that1 though it is very fireproof1 it is far from being waterproof4 ,in an exposed situation rain will drive completely through a tolerably stout brick wall4 ,if water be allowed to drop or fall against it1 the wall will become saturated like a sponge4 ,if the foot of a wall becomes wet1 or if the earth resting against the lower parts of it be moist1 water will1 if not checked1 rise to a great height in it1 and if the upper part of the wall be wet1 the water will sink downward4 ,with most sorts of brick the outer face absorbs moisture whenever the weather is moist2 and in time the action of the rain1 and the subsequent action of frost upon the moisture so taken up1 destroys the mortar in the joints1 which are to be seen perfectly open1 as if they had been raked out1 in old brickwork1 and in some cases 7happily not in many7 the action of weather destroys the bricks themselves1 the face decaying away1 and the brick becoming soft4 ,against this serious defect in our staple building material a series of precautions have been devised4 ,damp rising from the foot of the wall1 or from earth lying round its base1 is combated by a damp course--a bed of some impervious material going through the wall4 ,damp earth may be kept off by surrounding the walls with an open area or a closed one--usually termed a dry area4 ,damp against the face of the walls may be partly combated by a careful selection of a non-absorbent brick with a hard face and by struck joints4 ,but it is most effectually kept at bay by the expedient of building the wall hollow2 that is to say1 making the external wall of the house to consist of two perfectly distinct walls1 standing about #b in4 apart1 and held together by ties of earthenware or iron4 ,the result is that the moisture blowing through the outer skin does not pass the cavity1 but trickles down on the inner face of the outer wall1 while the inner wall remains dry4 ,the ties are constructed of shapes to prevent their conducting water themselves from without to the inner wall4 ,in addition to this1 a series of slates forming an intermediate protection is sometimes introduced1 and forms an additional and most valuable screen against weather4 ,sometimes1 the two skins of the wall are closer together--say in4--and the space is filled with a bituminous material4 ,a substance of a bituminous nature1 called hygeian rock1 has been of late years introduced1 and is being extensively used for this purpose2 it is melted and poured into the open space hot1 and quickly hardens4 ,the use of such a material is open to the objection that no air can pass through it4 ,the rooms of our houses are receiving air constantly through the walls1 and much of the constant current up our chimneys is supplied1 to our great advantage1 in this very imperceptible manner4 ,the house breathes1 so to speak1 through the pores of its brickwork4 ,when this is rendered impossible1 it seems clear that fiercer draughts will enter through the chinks and crevices1 and that there will be a greater demand upon flues not in use1 occasioning down draught in the chimneys4 ,another mode of keeping out weather is to cement the face of the brickwork4 ,but this hides up the work1 and so tends to promote bad work1 besides being often very unsightly4 ,among other peculiarities of brickwork are the facilities for introducing different colors and different textures of surface which it presents1 the ease with which openings and arches can be formed in it1 the possibility of executing ornament and even carving1 and the ease with which brickwork will combine with other building materials4 ,it cannot be well made use of for columns1 though it may readily enough be turned into piers or pilasters4 ,it cannot1 generally speaking1 with advantage be made use of for any large domes1 though the inner dome of ,st4 ,paul's and the intermediate cone are of brick1 and stand well4 ,but it is an excellent material for vaulting arcades and all purposes involving the turning of arches4 ,brickwork must be said to be durable1 but it requires care4 ,if not of the best1 brickwork within the reach of the constant vibration caused by the traffic on a railway seems to be in danger of being shaken to pieces1 judging from one or two instances that have come under my own observation4 ,the mortar1 and even in some cases the bricks themselves1 will rapidly deteriorate if moisture be allowed to get into the heart of a brick wall1 and in exposed situations this is very apt to happen4 ,care should always be taken to keep the pointing of external brickwork in good order1 and to maintain all copings and other projections intended to bar the access of water coming down from above1 and to stop the overflowing of gutters and stack pipes1 which soon soaks the wall through and through4 ,of course1 if there is a failure of foundations1 brickwork1 as was pointed out earlier1 becomes affected at once4 ,but if these be good1 and the materials used be sound ones1 and if the other precautions just recommended be taken1 it will last strong and sturdy for an immense length of time4 ,in some cases1 as for example in the ,roman ruins1 it has stood for #a1ejj years under every possible exposure and neglect1 and still shows something of a sturdy existence after all1 though sadly mutilated4 ,if we now return to the question1 ,what can be well done in brickwork8 no better answer can be given than to point to what has been and is being done1 especially in ,london and within our own reach and observation4 ,great engineering works1 such as railway viaducts1 the lining of railway tunnels1 the piers and even the arches of bridges1 sewage works1 dock and wharf walls1 furnace chimneys1 and other works of this sort are chiefly done in brickwork4 ,and notwithstanding that iron is far more used by the engineer for some purposes and concrete for others now than formerly1 still there is a great field for brickwork4 ,the late ,mr4 ,brunel1 who was fond of pushing size to extremes1 tried how wide a span he could arch over with brickwork4 ,and ,i believe the bridge which carries the ,g4,w4,r4 over the ,thames at ,maidenhead has the widest arch he or any other engineer has successfully erected in brick4 ,this arch has1 it is stated1 a span of #abh ft4 ,it is segmental1 the radius being #afi ft41 and the rise from springing to crown #bd ft41 and the depth of the arch #e ft4 #c in4 ,nowadays1 of course1 no one would dream of anything but an iron girder bridge in such a position4 ,mr4 ,brunel's father1 when he constructed the ,thames ,tunnel1 lined it with brickwork foot by foot as he went on1 and that lining sustained the heavy weight of the bed of the river and the river itself4 ,if you leave ,london by either of the southern lines1 all of which are at a high level1 you go for miles on viaducts consisting of brick arches carried on brick walls4 ,if you leave by the northern lines1 you plunge into tunnel after tunnel lined with brickwork1 and kept secure by such lining4 ,mile after mile of ,london streets1 and those in the suburbs1 present to the eye little but brick buildings2 dwelling houses1 shops1 warehouses1 succeed one another1 all in brickwork1 and even when the eye seems to catch a change1 it is more apparent than real4 ,the white mansions of ,tyburnia1 ,belgravia1 ,south ,kensington1 and the neat villas of the suburbs are only brickwork1 with a thin coat of stucco1 which serves the purpose of concealing the real structure--often only too much in need of concealment--with a material supposed to be a little more sightly1 and certainly capable of keeping the weather out rather more effectually than common brickwork would4 ,more than this1 such fine structures1 apparently built entirely of stone1 as are being put up for commercial purposes in the streets of the city1 and for public purposes throughout ,london1 are all of them nothing more than brick fabrics with a facing of masonry4 ,examine one of them in progress1 and you will find the foundations and vaults of brickwork1 and not only the interior walls1 but the main part of the front wall1 executed in brickwork1 and the stone only skin deep4 ,there are1 however1 two or three ways of making use of brickwork without covering it up1 and of gaining good architectural effects thereby1 and to these ,i beg now to direct your attention4 ,the architect who desires to make an effective brick building1 which shall honestly proclaim to all the world that it is of brick1 may do this1 and1 if he will1 may do it successfully1 by employing brickwork and no other material1 but making the best use of the opportunities which it affords1 or he may erect his building of brickwork and stone combined1 or of brickwork and terra cotta4 ,mr4 ,robson1 till lately the architect to the ,school ,board for ,london1 has the merit of having put down in every part of the metropolis a series of well contrived and well designed buildings1 the exterior of which almost without exception consists of brickwork only4 ,if you examine one of his school-houses1 you will see that the walls are of ordinary stock brickwork1 but usually brightened up by a little red brick at each angle1 and surmounted by well contrasted gables and with lofty1 well designed chimneys1 rising from the tiled roof4 ,the window openings and doorways are marked by brickwork1 usually also red1 and sometimes moulded1 and though ,i personally must differ from the taste which selected some of the forms employed 7they are those in use in this country in the #agth and the last centuries71 ,i cordially recognize that with very simple and inexpensive means exceedingly good1 appropriate1 and effective buildings have been designed4 ,among examples of architecture wholly1 or almost wholly1 executed in red brick1 ,i cannot pass over a building built many years ago1 little known on account of its obscure situation1 but a gem in its way4 ,i allude to the schools designed by ,mr4 ,wilde1 and built in ,castle street1 ,endell street4 ,of buildings where a small amount of stone is introduced into brickwork we have a good many fine specimens in ,london4 ,one of the best--probably the best--is the library in ,lincoln's ,inn ,fields4 ,this is a large and picturesque pile1 built under ,mr4 ,hardwick1 as architect1 in red brick1 with patterns in the blank parts of the walls done in black brick4 ,it has splendid moulded brick chimneys1 and the mullions of the windows1 the copings1 the entrances1 and some other architectural features done in stone4 ,the building is a good reproduction of the style of building in ,tudor times1 when1 as has been already mentioned1 brickwork was taken into favor4 ,another building of the same class1 but not so good1 is the older part of the ,consumption ,hospital1 at ,brompton4 ,brickwork1 with a little stone1 has been very successfully employed as the material for churches1 and in many such cases the interior is of unplastered brickwork4 ,such churches often attain1 when designed by skillful hands1 great dignity and breadth of effect4 ,st4 ,albans1 ,holborn2 the great church designed by ,mr4 ,butterfield1 in ,margaret street2 ,mr4 ,street's church near ,vincent square1 ,westminster2 and several churches of ,mr4 ,brooks'1 such as he was kind enough to enable me to illustrate tonight1 may be mentioned as examples of the sort4 ,mr4 ,waterhouse has built an elaborate ,congregational church at ,hampstead1 which shows the use with which such effects of color may be obtained in interiors1 and has kindly lent some drawings4 ,mr4 ,pearson's church at ,kilburn may also be referred to as a fine example of brick vaulting4 ,brick and terra cotta seem to have a natural affinity for one another4 ,terra cotta is no more than a refined brick1 made of the same sort of material1 only in every respect more carefully1 and kiln baked4 ,its similarity to brick is such that there is no sense of incongruity if moulded or carved brickwork and terra cotta are both employed in the same building1 and this can hardly be said to be the case if the attempt is made to combine ornamental brickwork and stone ornaments4 ,at ,south ,kensington1 a whole group of examples of brickwork with terra cotta meet us4 ,the ,natural ,history ,museum1 the finest of them all1 is hardly fit for our present purpose1 as it is as completely encased in terra cotta as the fronts of the buildings in this avenue are in stone4 ,but here are the ,albert ,hall1 a fine specimen of mass and effect2 the ,city and ,guilds ,institute2 the ,college of ,music1 and some private houses and blocks of flats1 all in red brick with terra cotta1 and all showing the happy manner in which the two materials can be blended4 ,in most of them there is a contrast of color2 but ,mr4 ,waterhouse1 in the ,technical ,institute1 has employed red terra cotta with red bricks1 as he also has done in his fine ,st4 ,paul's ,school at ,hammersmith1 and ,mr4 ,norman ,shaw has1 in his fine pile of buildings in ,st4 ,james' street4 ,this combination--namely1 brick and terra cotta--,i look upon as the best for withstanding the ,london climate1 and for making full use of the capabilities of brickwork that can be employed1 and ,i have no doubt that in the future it will be frequently resorted to4 ,some of those examples also show the introduction of cast ornaments1 and others the employment of carving as means of enriching the surface of brick walls with excellent effect4 ,here we must leave the subject2 but in closing1 ,i cannot forbear pointing to the art of the bricklayer as a fine example of what may be accomplished by steady perseverance4 ,every brick in the miles of viaducts or tunnels1 houses1 or public buildings1 to which we have made allusion1 was laid separately1 and it is only steady perseverance1 brick after brick1 on the part of the bricklayer1 which could have raised these great masses of work4 ,let me add that no one brick out of the many laid is of no importance4 ,some time ago a great fire occurred in a public asylum1 and about #b1jjj of damage was done1 and the lives of many of the inmates endangered4 ,when the origin of this fire came to be traced out1 it was found that it was due to one brick being left out in a flue4 ,a penny would be a high estimate of the cost of that brick and of the expense of laying it1 yet through the neglect of that pennyworth1 #b1jjj damage was done1 and risk of human life was run4 ,i think there is a moral in this story which each of us can make out if he will4 99 99 99 99 99 ,a fireproof whitewash can be readily made by adding one part silicate of soda 7or potash7 to every five parts of whitewash4 ,the addition of a solution of alum to whitewash is recommended as a means to prevent the rubbing off of the wash4 ,a coating of a good glue size made by dissolving half a pound of glue in a gallon of water is employed when the wall is to be papered4 99 99 99 99 99 ,,phenomena ,,of ,,alternating ,,currents4 ,footnote3 ,from a paper read before the recent meeting of the ,american ,institute of ,electrical ,engineers1 ,new ,york1 and reported in the ,electrical ,world4 ,by ,prof4 ,,elihu ,,thomson4 ,the actions produced and producible by the agency of alternating currents of considerable energy are assuming greater importance in the electric arts4 ,i mean1 of course1 by the term alternating currents1 currents of electricity reversed at frequent intervals1 so that a positive flow is succeeded by a negative flow1 and that again by a positive flow1 such reversals occurring many times in a second1 so that the curve of current of electromotive force will1 if plotted1 be a wave line1 the amplitude of which is the arithmetical sum of the positive and negative maxima of current or electromotive force1 as the case may be1 while a horizontal middle line joins the zero points of current or electromotive force4 ,illustration3 ,,fig4 #a ,it is well known that such a current passing in a coil or conductor laid parallel with or in inductive relation to a second coil or conductor1 will induce in the second conductor1 if on open circuit1 alternating electromotive forces1 and that if its terminals be closed or joined1 alternating currents of the same rhythm1 period1 or pitch1 will circulate in the second conductor4 ,this is the action occurring in any induction coil whose primary wire is traversed by alternating currents1 and whose secondary wire is closed either upon itself directly or through a resistance4 ,what ,i desire to draw attention to in the present paper are the mechanical actions of attraction and repulsion which will be exhibited between the two conductors1 and the novel results which may be obtained by modifications in the relative dispositions of the two conductors4 ,illustration3 ,,fig4 #b4 ,in #ahhd1 while preparing for the ,international ,electrical ,exhibition at ,philadelphia1 we had occasion to construct a large electro-magnet1 the cores of which were about six inches in diameter and about twenty inches long4 ,they were made of bundles of iron rod of about #e_/af inch diameter4 ,when complete1 the magnet was energized by the current of a dynamo giving continuous currents1 and it exhibited the usual powerful magnetic effects4 ,it was found also that a disk of sheet copper1 of about #a_/af inch thickness and #aj inches in diameter1 if dropped flat against a pole of the magnet1 would settle down softly upon it1 being retarded by the development of currents in the disk due to its movement in a strong magnetic field1 and which currents were of opposite direction to those in the coils of the magnet4 ,in fact1 it was impossible to strike the magnet pole a sharp blow with the disk1 even when the attempt was made by holding one edge of the disk in the hand and bringing it down forcibly toward the magnet4 ,in attempting to raise the disk quickly off the pole1 a similar but opposite action of resistance to movement took place1 showing the development of currents in the same direction to those in the coils of the magnet1 and which currents1 of course1 would cause attraction as a result4 ,illustration3 ,fig4 #c ,the experiment was1 however1 varied1 as in ,fig4 #a4 ,the disk1 ,d1 was held over the magnet pole1 as shown1 and the current in the magnet coils cut off by shunting them4 ,there was felt an attraction of the disk or a dip toward the pole4 ,the current was then put on by opening the shunting switch1 and a repulsive action or lift of the disk was felt4 ,the actions just described are what would be expected in such a case1 for when attraction took place1 currents had been induced in the disk1 ,d1 in the same direction as those in the magnet coils beneath it1 and when repulsion took place the induced current in the disk was of opposite character or direction to that in the coils4 ,illustration3 ,fig4 #d ,now let us imagine the current in the magnet coils to be not only cut off1 but reversed back and forth4 ,for the reasons just given1 we will find that the disk1 ,d1 is attracted and repelled alternately2 for1 whenever the currents induced in it are of the same direction with those in the inducing or magnet coil1 attraction will ensue1 and when they are opposite in direction1 repulsion will be produced4 ,moreover1 the repulsion will be produced when the current in the magnet coil is rising to a maximum in either direction1 and attraction will be the result when the current of either direction is falling to zero1 since in the former case opposite currents are induced in the disk1 ,d1 in accordance with well known laws1 and in the latter case currents of the same direction will exist in the disk1 ,d1 and the magnet coil4 ,the disk might1 of course1 be replaced by a ring of copper or other good conductor1 or by a closed coil of bare or insulated wire1 or by a series of disks1 rings or coils superposed1 and the results would be the same4 ,thus far1 indeed1 we have nothing of a particularly novel character1 and1 doubtless1 other experimenters have made very similar experiments and noted similar results to those described4 ,illustration3 ,,fig4 #e ,the account just given of the effects produced by alternating currents1 while true1 is not the whole truth1 and just here we may supplement it by the following statements3 ,an alternating current circuit or coil repels and attracts a closed circuit or coil placed in direct or magnetic inductive relation therewith2 but the repulsive effect is in excess of the attractive effect4 ,when the closed circuit or coil is so placed1 and is of such low resistance metal that a comparatively large current can circulate as an induced current1 so as to be subject to a large self-induction1 the repulsive far exceeds the attractive effort4 ,for want of a better name1 ,i shall call this excess of repulsive effect the electro-inductive repulsion of the coils or circuits4 ,illustration3 ,,fig4 #f4 ,this preponderating repulsive effect may be utilized or may show its presence by producing movement or pressure in a given direction1 by producing angular deflection as of a pivoted body1 or by producing continuous rotation with a properly organized structure4 ,some of the simple devices realizing the conditions ,i will now describe4 ,illustration3 ,,fig4 #g4 ,in ,fig4 #b1 ,c is a coil traversed by alternating currents4 ,b is a copper case or tube surrounding it1 but not exactly over its center4 ,the copper tube1 ,b1 is fairly massive and is the seat of heavy induced currents4 ,there is a preponderance of repulsive action1 tending to force the two conductors apart in an axial line4 ,the part1 ,b1 may be replaced by concentric tubes slid one in the other1 or by a pile of flat rings1 or by a closed coil of coarse or fine wire insulated1 or not4 ,if the coil1 ,c1 or primary coil1 is provided with an iron core such as a bundle of fine iron wires1 the effects are greatly increased in intensity1 and the repulsion with a strong primary current may become quite vigorous1 many pounds of thrust being producible by apparatus of quite moderate size4 ,the forms and relations of the two parts1 ,c and ,b1 may be greatly modified1 with the general result of a preponderance of repulsive action when the alternating currents circulate4 ,fig4 #c shows the part1 ,b1 of an internally tapered or coned form1 and ,c of an externally coned form1 wound on an iron wire bundle1 ,i4 ,the action in ,fig4 #b may be said to be analogous to that of a plain solenoid with its core1 except that repulsion1 and not attraction1 is produced1 while that of ,fig4 #c is more like the action of tapered or conically wound solenoids and taper cores4 ,of course1 it is unnecessary that both be tapered4 ,the effect of such shaping is simply to modify the range of action and the amount of repulsive effort existing at different parts of the range4 ,illustration3 ,,fig4 #h4 ,in ,fig4 #d the arrangement is modified so that the coil1 ,c1 is outside1 and the closed band or circuit1 ,b1 inside and around the core1 ,i4 ,electro-inductive repulsion is produced as before4 ,it will be evident that the repulsive actions will not be mechanically manifested by axial movement or effort when the electrical middles of the coils or circuits are coincident4 ,in cylindrical coils in which the current is uniformly distributed through all the parts of the conductor section1 what ,i here term the electrical middle1 or the center of gravity of the ampere turns of the coils1 will be the plane at right angles to its axis at its middle1 that of ,b and ,c1 in ,fig4 #d1 being indicated by a dotted line4 ,to repeat1 then1 when the centers or center planes of the conductors1 ,fig4 #d1 coincide1 no indication of electro-inductive repulsion is given1 because it is mutually balanced in all directions2 but when the coils are displaced1 a repulsion is manifested1 which reaches a maximum at a position depending on the peculiarities of proportion and distribution of current at any time in the two circuits or conductors4 ,illustration3 ,,fig4 #i4 ,it is not my purpose now to discuss the ways of determining the distribution of currents and mechanical effects1 as that would extend the present paper much beyond its intended limit4 ,the forms and relative arrangement of the two conductors may be greatly varied4 ,in ,fig4 #e the parts are of equal diameter1 one1 ,b1 being a closed ring1 and the other1 ,c1 being an annular coil placed parallel thereto2 and an iron core or wire bundle placed in the common axis of the two coils increases the repulsive action4 ,b may be simply a disk or plate of any form1 without greatly affecting the nature of the action produced4 ,it may also be composed of a pile of copper washers or a coil of wire1 as before indicated4 ,illustration3 ,,fig4 #aj4 ,an arrangement of parts somewhat analogous to that of a horseshoe electro magnet and armature is shown in ,fig4 #f4 ,the alternating current coils1 ,c ,c'1 are wound upon an iron wire bundle bent into ,u form1 and opposite its poles is placed a pair of thick copper disks1 ,b ,b'1 which are attracted and repelled1 but with an excess of repulsion depending on their form1 thickness1 etc4 ,illustration3 ,,fig4 #aa4 ,if the iron core takes the form of that shown by ,i ,i1 ,fig4 #g1 such as a cut ring with the coil1 ,c1 wound thereon1 the insertion of a heavy copper plate1 ,b1 into the slot or divided portion of the ring will be opposed by a repulsive effort when alternating currents pass in ,c4 ,this was the first form of device in which ,i noticed the phenomenon of repulsive preponderance in question4 ,the tendency is to thrust the plate1 ,b1 out of the slot in the ring excepting only when its center is coincident with the magnetic axis joining the poles of the ring between which ,b is placed4 ,if the axes of the conductors1 ,fig4 #e1 are not coincident1 but displaced1 as in ,fig4 #h1 then1 besides a simple repulsion apart1 there is a lateral component or tendency1 as indicated by the arrows4 ,akin to this is the experiment illustrated in ,fig4 #i4 ,here the closed conductor1 ,b1 is placed with its plane at right angles to that of ,c1 wound on a wire bundle4 ,the part1 ,b1 tends to move toward the center of the coil1 ,c1 so that its axis will be in the middle plane of ,c1 transverse to the core1 as indicated by the dotted line4 ,this leads us at once to another class of actions1 i4e41 deflective actions4 ,illustration3 ,,fig4 #ab4 ,when one of the conductors1 as ,b1 ,fig4 #aj1 composed of a disk1 or1 better1 of a pile of thin copper disks1 or of a closed coil of wire1 is mounted on an axis1 ,x1 transverse to the axis of coil1 ,c1 through which coil the alternating current passes1 a deflection of ,b to the position indicated by dotted lines will take place1 unless the plane of ,b is at the start exactly coincident with that of ,c4 ,if slightly inclined at the start1 deflection will be caused as stated4 ,it matters not whether the coil1 ,c1 incloses the part1 ,b1 or be inclosed by it1 or whether the coil1 ,c1 be pivoted and ,b fixed1 or both be pivoted4 ,in ,fig4 #aa the coil1 ,c1 surrounds an iron wire core1 and ,b is pivoted above it1 as shown4 ,it is deflected1 as before1 to the position indicated in dotted lines4 ,illustration3 ,,fig4 #ac ,it is important to remark here that in cases where deflection is to be obtained1 as in ,figs4 #aj and #aa1 ,b had best be made of a pile of thin washers or a closed coil of insulated wire instead of a solid ring4 ,this avoids the lessening of effect which would come from the induction of currents in the ring1 ,b1 in other directions than parallel to its circumference4 ,illustration3 ,,fig4 #ad4 ,we will now turn our attention to the explanation of the actions exhibited1 and afterward refer to their possible applications4 ,it may be stated as certainly true that were the induced currents in the closed conductor unaffected by any self-induction1 the only phenomena exhibited would be alternate equal attractions and repulsions1 because currents would be induced in opposite directions to that of the primary current when the latter current was changing from zero to maximum positive or negative current1 so producing repulsion2 and would be induced in the same direction when changing from maximum positive or negative value to zero1 so producing attraction4 ,this condition can be illustrated by a diagram1 ,fig4 #ab4 ,here the lines of zero current are the horizontal straight lines4 ,the wavy lines represent the variations of current strength in each conductor1 the current in one direction being indicated by that portion of the curve above the zero line1 and in the other direction by that portion below it4 ,the vertical dotted lines simply mark off corresponding portions of phase or succession of times4 ,illustration3 ,,fig4 #ae ,here it will be seen that in the positive primary current descending from m1 its maximum1 to the zero line1 the secondary current has risen from its zero to m1 its maximum4 ,attraction will therefore ensue1 for the currents are in the same direction in the two conductors4 ,when the primary current increases from zero to its negative maximum1 n1 the positive current in the secondary closed circuit will be decreasing from m1 its positive maximum1 to zero2 but1 as the currents are in opposite directions1 repulsion will occur4 ,these actions of attraction and repulsion will be reproduced continually1 there being a repulsion1 then an attraction1 then a repulsion1 and again an attraction1 during one complete wave of the primary current4 ,the letters1 r1 a1 at the foot of the diagram1 ,fig4 #ab1 indicate this succession4 ,in reality1 however1 the effects of self-induction in causing a lag1 shift1 or retardation of phase in the secondary current will considerably modify the results1 and especially so when the secondary conductor is constructed so as to give to such self-induction a large value4 ,in other words1 the maxima of the primary or inducing current will no longer be found coincident with the zero points of the secondary currents4 ,the effect will be the same as if the line representing the wave of the secondary current in ,fig4 #ab had been shifted forward to a greater or less extent4 ,this is indicated in diagram1 ,fig4 #ac4 ,it gives doubtless an exaggerated view of the action1 though from the effects of repulsion which ,i have produced1 ,i should say it is by no means an unrealizable condition4 ,illustration3 ,fig4 #af4 ,it will be noticed that the period during which the currents are opposite1 and during which repulsion can take place1 is lengthened at the expense of the period during which the currents are in the same direction for attractive action4 ,these differing periods are marked r1 a1 etc41 or the period during which repulsion exists is from the zero of the primary or inducing current to the succeeding zero of the secondary or induced current2 and the period during which attraction exists is from the zero of the induced current to the zero of inducing current4 ,but far more important still in giving prominence to the repulsive effect than this difference of effective period is the fact that during the period of repulsion both the inducing and induced currents have their greatest values1 while during the period of attraction the currents are of small amounts comparatively4 ,this condition may be otherwise expressed by saying that the period during which repulsion occurs includes all the maxima of current1 while the period of attraction includes no maxima4 ,there is then a repulsion due to the summative effects of strong opposite currents for a lengthened period1 against an attraction due to the summative effects of weak currents of the same direction during a shortened period1 the resultant effect being a greatly preponderating repulsion4 ,it is now not difficult to understand all the actions before described as obtained with the varied relations of coils1 magnetic fields1 and closed circuits4 ,it will be easily understood1 also1 that an alternating magnetic field is in all respects the same as an alternating current coil in producing repulsion on the closed conductor1 because the repulsions between the two conductors are the result of magnetic repulsions arising from opposing fields produced by the coils when the currents are of opposite directions in them4 ,thus far ,i have applied the repulsive action described in the construction of alternating current indicators1 alternating current arc lamps1 regulating devices for alternating currents1 and to rotary motors for such currents4 ,for current indicators1 a pivoted or suspended copper band or ring composed of thin washers piled together and insulated from one another1 and made to carry a pointer or index has been placed in the axis of a coil conveying alternating currents whose amount or potential is to be indicated4 ,gravity or a spring is used to bring the index to the zero of a divided scale1 at which time the plane of the copper ring or band makes an angle of1 say1 #ae degrees to #bj degrees with the plane of the coil4 ,this angle is increased by deflection more or less great1 according to the current traversing the coil4 ,the instrument can be calibrated for set conditions of use4 ,time would not permit of a full description of these arrangements as made up to the present4 ,in arc lamps the magnet for forming the arc can be composed of a closed conductor1 a coil for the passage of current1 and an iron wire core4 ,the repulsive action upon the closed conductor lifts and regulates the carbons in much the same manner that electro magnets do when continuous currents are used4 ,the electro-inductive repulsive action has also been applied to regulating devices for alternating currents1 with the details of which ,i cannot now deal4 ,for the construction of an alternating current motor which can be started from a state of rest the principle has also been applied1 and it may here be remarked that a number of designs of such motors is practicable4 ,one of the simplest is as follows3 ,the coils1 ,c1 ,fig4 #ad1 are traversed by an alternating current and are placed over a coil1 ,b1 mounted upon a horizontal axis1 transverse to the axis of the coil1 ,c4 ,the terminals of the coil1 ,b1 which is wound with insulated wire1 are carried to a commutator1 the brushes being connected by a wire1 as indicated4 ,the commutator is so constructed as to keep the coil1 ,b1 on short circuit from the position of coincidence with the plane of ,c to the position where the plane of ,b is at right angles to that of ,c2 and to keep the coil1 ,b1 open-circuited from the right-angled position1 or thereabouts1 to the position of parallel or coincident planes4 ,the deflective repulsion exhibited by ,b will1 when its circuit is completed by the commutator and brushes1 as described1 act to place its plane at right angles to that of ,c2 but being then open-circuited1 its momentum carries it to the position just past parallelism1 at which moment it is again short-circuited1 and so on4 ,it is capable of very rapid rotation1 but its energy is small4 ,i have1 however1 extended the principle to the construction of more complete apparatus4 ,one form has its revolving portion or armature composed of a number of sheet iron disks wound as usual with three coils crossing near the shaft4 ,the commutator is arranged to short-circuit each of these coils in succession1 and twice in a revolution1 and for a period of #ij-;degrees of rotation each4 ,the field coils surround the armature1 and there is a laminated iron field structure completing the magnetic circuit4 ,i may say here that surrounding the armature of a dynamo by the field coils1 though very recently put forth as a new departure1 was described in various ,thomson-,houston patents1 and to a certain extent all ,thomson-,houston machines embody this feature4 ,figs4 #ae and #af will give an idea of the construction of the motor referred to4 ,,cc' are the field coils or inducing coils1 which alone are put into the alternating current circuit4 ,,ii is a mass of laminated iron1 in the interior of which the armature revolves1 with its three coils1 ,b1 ,b1 ,b1 wound on a core of sheet iron disks4 ,the commutator short-circuits the armature coils in succession in the proper positions to utilize the repulsive effect set up by the currents which are induced in them by the alternations in the field coils4 ,the motor has no dead point1 and will start from a state of rest and give out considerable power1 but with what economy is not yet known4 ,a curious property of the machine is that at a certain speed1 depending on the rapidity of the alternations in the coil1 ,c1 a continuous current passes from one commutator brush to the other1 and it will energize electro magnets and perform other actions of direct currents4 ,here we have1 then1 a means of inducing direct currents from alternating currents4 ,to control the speed and keep it at that required for the purpose1 we have only to properly gear the motor to another of the ordinary type for alternating currents1 namely1 an alternating-current dynamo used as a motor4 ,the charging of storage batteries would not be difficult with such a machine1 even from an alternating-current line1 though the losses might be considerable4 99 99 99 99 99 ,,photographic ,,study ,,of ,,stellar ,,spectra1 ,,harvard ,,college ,,observatory4 ,,henry ,,draper ,,memorial4 ,first ,annual ,report4 ,dr4 ,henry ,draper1 in #ahgb1 was the first to photograph the lines of a stellar spectrum4 ,his investigation1 pursued for many years with great skill and ingenuity1 was most unfortunately interrupted in #ahhb by his death4 ,the recent advances in dry-plate photography have vastly increased our powers of dealing with this subject4 ,early in #ahhf1 accordingly1 ,mrs4 ,draper made a liberal provision for carrying on this investigation at the ,harvard ,college ,observatory1 as a memorial to her husband4 ,the results attained are described below1 and show that an opportunity is open for a very important and extensive investigation in this branch of astronomical physics4 ,mrs4 ,draper has accordingly decided greatly to extend the original plan of work1 and to have it conducted on a scale suited to its importance4 ,the attempt will be made to include all portions of the subject1 so that the final results shall form a complete discussion of the constitution and conditions of the stars1 as revealed by their spectra1 so far as present scientific methods permit4 ,it is hoped that a greater advance will thus be made than if the subject was divided among several institutions1 or than if a broader range of astronomical study was attempted4 ,it is expected that a station to be established in the southern hemisphere will permit the work to be extended so that a similar method of study may be applied to stars in all parts of the sky4 ,the investigations already undertaken1 and described below more in detail1 include a catalogue of the spectra of all stars north of--#bd of the sixth magnitude and brighter1 a more extensive catalogue of spectra of stars brighter than the eighth magnitude1 and a detailed study of the spectra of the bright stars4 ,this last will include a classification of the spectra1 a determination of the wave lengths of the lines1 a comparison with terrestrial spectra1 and an application of the results to the measurement of the approach and recession of the stars4 ,a special photographic investigation will also be undertaken of the spectra of the banded stars1 and of the ends of the spectra of the bright stars4 ,the instruments employed are an eight inch ,voigtlander photographic lens1 reground by ,alvan ,clark ,sons1 and ,dr4 ,draper's #aa inch photographic lens1 for which ,mrs4 ,draper has provided a new mounting and observatory4 ,the #ae inch refractor belonging to the ,harvard ,college ,observatory has also been employed in various experiments with a slit spectroscope1 and is again being used as described below4 ,mrs4 ,draper has decided to send to ,cambridge a #bh inch reflector and its mountings1 and a #ae inch mirror1 which is one of the most perfect reflectors constructed by ,dr4 ,draper1 and with which his photograph of the moon was taken4 ,the first two instruments mentioned above have been kept at work during the first part of every clear night for several months4 ,it is now intended that at least three telescopes shall be used during the whole night1 until the work is interrupted by daylight4 ,the spectra have been produced by placing in front of the telescope a large prism1 thus returning to the method originally employed by ,fraunhofer in the first study of stellar spectra4 ,four #ae prisms have been constructed1 the three largest having clear apertures of nearly eleven inches1 and the fourth being somewhat smaller4 ,the entire weight of these prisms exceeds a hundred pounds1 and they fill a brass cubical box a foot on each side4 ,the spectrum of a star formed by this apparatus is extremely narrow when the telescope is driven by clockwork in the usual way4 ,a motion is accordingly given to the telescope slightly differing from that of the earth by means of a secondary clock controlling it electrically4 ,the spectrum is thus spread into a band1 having a width proportional to the time of exposure and to the rate of the controlling clock4 ,this band is generally not uniformly dense4 ,it exhibits lines perpendicular to the refracting edge of the prism1 such as are produced in the field of an ordinary spectroscope by particles of dust upon the slit4 ,in the present case1 these lines may be due to variations in the transparency of the air during the time of exposure1 or to instrumental causes1 such as irregular running of the driving clock1 or slight changes in the motion of the telescope1 resulting from the manner in which its polar axis is supported4 ,these instrumental defects may be too small to be detected in ordinary micrometric or photographic observations1 and still sufficient to affect the photographs just described4 ,a method of enlargement has been tried which gives very satisfactory results1 and removes the lines above mentioned as defects in the negatives4 ,a cylindrical lens is placed close to the enlarging lens1 with its axis parallel to the length of the spectrum4 ,in the apparatus actually employed1 the length of the spectrum1 and with it the dispersion1 is increased five times1 while the breadth is made in all cases about four inches4 ,the advantage of this arrangement is that it greatly reduces the difficulty arising from the feeble light of the star4 ,until very lately1 the spectra in the original negatives were made very narrow1 since otherwise the intensity of the starlight would have been insufficient to produce the proper decomposition of the silver particles4 ,the enlargement being made by daylight1 the vast amount of energy then available is controlled by the original negative1 the action of which may be compared to that of a telegraphic relay4 ,the copies therefore represent many hundred times the original energy received from the stars4 ,if care is not taken1 the dust and irregularities of the film will give trouble1 each foreign particle appearing as a fine spectral line4 ,our methods of enlargement have been considered1 and some of them tried1 with the object of removing the irregularities of the original spectra without introducing new defects4 ,for instance1 the sensitive plate may be moved during the enlargement in the direction of the spectral lines2 a slit parallel to the lines may be used as the source of light1 and the original negative separated by a small interval from the plate used for the copy2 or two cylindrical lenses may be used1 with their axes perpendicular to each other4 ,in some of these ways the lines due to dust might either be avoided or so much reduced in length as not to resemble the true lines of the spectrum4 ,the #ae inch refractor is now being used with a modification of the apparatus employed by ,dr4 ,draper in his first experiments--a slit spectroscope from which the slit has been removed4 ,a concave lens has been substituted for the collimator and slit1 and besides other advantages1 a great saving in length is secured by this change4 ,it is proposed to apply this method to the #bh inch reflector1 thus utilizing its great power of gathering light4 ,a description of an accompanying plate here follows1 which is omitted1 as the plate cannot be easily reproduced for ordinary press printing4 ,the results to be derived from the large number of photographs already obtained can only be stated after a long series of measurements and a careful reduction and discussion of them4 ,an inspection of the plates1 however1 shows some points of interest4 ,a photograph of a ,cygni1 taken ,november1 #bf1 #ahhf1 shows that the ,h line is double1 its two components having a difference in wave length of about one ten-millionth of a millimeter4 ,a photograph of o ,ceti shows that the lines ,g and h are bright1 as are also four of the ultra-violet lines characteristic of spectra of the first type4 ,the ,h and ,k lines in this spectrum are dark1 showing that they probably do not belong to that series of lines4 ,the star near chi' ,orionis1 discovered by ,gore1 in ,december1 #ahhe1 gives a similar spectrum1 which affords additional evidence that it is a variable of the same class as o ,ceti4 ,spectra of ,sirius show a large number of faint lines besides the well-known broad lines4 ,the dispersion employed in any normal map of the spectrum may be expressed by its scale1 that is1 by the ratio of the wave length as represented to the actual wave length4 ,it will be more convenient to divide these ratios by one million1 to avoid the large numbers otherwise involved4 ,if one millionth of a millimeter is taken as the unit of wave length1 the length of this unit on the map in millimeters will give the same measure of the dispersion as that just described4 ,when the map is not normal1 the dispersion of course varies in different parts4 ,it increases rapidly toward the violet end when the spectrum is formed by a prism4 ,accordingly1 in this case the dispersion given will be that of the point whose wave length is #djj4 ,this point lies near the middle of the photographic spectrum when a prism is used1 and is not far from the ,h line4 ,the dispersion may accordingly be found with sufficient accuracy by measuring the interval between the ,h and ,k lines1 and dividing the result in millimeters by #c4d1 since the difference in their wave lengths equals this quantity4 ,the following examples serve to illustrate the dispersion expressed in this way3 ,angstrom1 ,cornu1 #aj2 ,draper1 photographer of normal solar spectrum1 #c4a and #e4b2 ,rowland1 #bc1 #cc1 and #df2 ,draper1 stellar spectra1 #j4af2 ,huggins1 #j4a4 ,the most rapid plates are needed in this work1 other considerations being generally of less importance4 ,accordingly1 the ,allen and ,rowell extra quick plates have been used until recently4 ,it was found1 however1 that they were surpassed by the ,seed plates ,no4 #ba1 which were accordingly substituted for them early in ,december4 ,recognizing the importance of supplying this demand for the most sensitive plates possible1 the ,seed ,company have recently succeeded in making still more sensitive plates1 which we are now using4 ,the limit does not seem to be reached even yet4 ,plates could easily be handled if the sensitiveness were increased tenfold4 ,a vast increase in the results may be anticipated with each improvement of the plates in this respect4 ,apparatus for testing plates1 which is believed to be much more accurate than that ordinarily employed1 is in course of preparation4 ,it is expected that a very precise determination will be made of the rapidity of the plates employed4 ,makers of very rapid plates are invited to send specimens for trial4 ,the photographic work has been done by ,mr4 ,w4,p4 ,gerrish1 who has also rendered important assistance in other parts of the investigation4 ,he has shown great skill in various experiments which have been tried1 and in the use of various novel and delicate instruments4 ,many of the experimental difficulties could not have been overcome but for the untiring skill and perseverance of ,mr4 ,george ,b4 ,clark1 of the firm of ,alvan ,clark ,sons1 by whom all the large instruments have been constructed4 ,the progress of the various investigations which are to form a part of this work is given below3 #a4 ,catalogue of ,spectra of ,bright ,stars4--,this is a continuation of the work undertaken with the aid of an appropriation from the ,bache fund1 and described in the ,memoirs of the ,american ,academy1 vol4 xi41 p4 #baj4 ,the #h inch telescope is used1 each photograph covering a region of #aj square4 ,the exposures for equatorial stars last for five minutes1 and the rate of the clock is such that the spectra have a width of about #j4a cm4 ,the length of the spectra is about #a4b cm4 for the brighter1 and #j4f cm4 for the fainter stars4 ,the dispersion of the scale proposed above is #j4a4 ,the spectra of all stars of the sixth magnitude and brighter will generally be found upon these plates1 except in the case of red stars4 ,many fainter blue stars also appear4 ,three or four exposures are made upon a single plate4 ,the entire sky north of -#bd would be covered twice1 according to this plan1 with #ahj plates and #fij exposures4 ,it is found preferable in some cases to make only two exposures2 and when the plate appears to be a poor one1 the work is repeated4 ,the number of plates is therefore increased4 ,last summer the plates appeared to be giving poor results4 ,dust on the prisms seemed to be the explanation of this difficulty4 ,many regions were reobserved on this account4 ,the first cycle1 covering the entire sky from zero to twenty-four hours of right ascension1 has been completed4 ,the work will be finished during the coming year by a second cycle of observations1 which has already been begun4 ,the first cycle contains #beg plates1 all of which have been measured1 and a large part of the reduction completed4 #h1cac spectra have been measured on them1 nearly all of which have been identified1 and the places of a greater portion of the stars brought forward to the year #aijj1 and entered in catalogue form4 ,in the second cycle1 #fd plates have been taken1 and about as many more will be required4 #ea plates have been measured and identified1 including #b1igd spectra4 ,a study of the photographic brightness and distribution of the light in the spectra will also be made4 ,the results will be published in the form of a catalogue resembling the ,photometric ,catalogue given in volume xiv4 of the ,annals of ,harvard ,college ,observatory4 ,it will contain the approximate place of each star for #aijj1 its designation1 the character of the spectrum as derived from each of the plates in which it was photographed1 the references to these plates1 and the photographic brightness of the star4 #b4 ,catalogue of ,spectra of ,faint ,stars4--,this work resembles the preceding1 but is much more extensive4 ,the same instrument is used1 but each region has an exposure of an hour1 the rate of the clock being such that the width of the spectrum will be as before #j4a cm4 ,many stars of the ninth magnitude will thus be included1 and nearly all brighter than the eighth4 ,in one case1 over three hundred spectra are shown on a single plate4 ,this work has been carried on only in the intervals when the telescope was not needed for other purposes4 #ii plates have1 however1 been obtained1 and on these #d1ddb spectra have been measured4 ,it is proposed to complete the equatorial zones first1 gradually extending the work northward4 ,in all1 #ae1gbi spectra of bright and faint stars have been measured4 #c4 ,detailed ,study of the ,spectra of the ,brighter ,stars4--,this work has been carried on with the #aa inch photographic telescope used by ,dr4 ,draper in his later researches4 ,a wooden observatory was constructed about #bj feet square4 ,this was surmounted by a dome having a clear diameter of #ah feet on the inside4 ,the dome had a wooden frame1 sheathed and covered with canvas4 ,it rested on eight cast iron wheels1 and was easily moved by hand1 the power being directly applied4 ,work was begun upon it in ,june1 and the first observations were made with the telescope in ,october4 ,two prisms were formed by splitting a thick plate of glass diagonally4 ,these gave such good results that two others were made in the same way1 and the entire battery of four prisms is ordinarily used4 ,the safety and convenience of handling the prisms is greatly increased by placing them in square brass boxes1 each of which slides into place like a drawer4 ,any combination of the prisms may thus be employed4 ,as is usual in such an investigation1 a great variety of difficulties have been encountered1 and the most important of them have now been overcome4 #d4 ,faint ,stellar ,spectra4--,the #bh inch reflector will be used for the study of the spectra of the faint stars1 and also for the fainter portions near the ends of the spectra of the brighter stars4 ,the form of spectroscope mentioned above1 in which the collimator and slit are replaced by a concave lens1 will be tried4 ,the objects to be examined are1 first1 the stars known to be variable1 with the expectation that some evidence may be afforded of the cause of the variation4 ,the stars whose spectrum is known to be banded1 to contain bright lines1 or to be peculiar in other respects1 will also be examined systematically4 ,experiments will also be tried with orthochromatic plates and the use of a colored absorbing medium1 in order to photograph the red portions of the spectra of the bright stars4 ,quartz will also be tried to extend the images toward the ultra-violet4 #e4 ,absorption ,spectra4--,the ordinary form of comparison spectrum cannot be employed on account of the absence of a slit4 ,the most promising method of determining the wave lengths of the stellar spectra is to interpose some absorbent medium4 ,experiments are in progress with hyponitric fumes and other substances4 ,a tank containing one of these materials is interposed and the spectra photographed through it4 ,the stellar spectra will then be traversed by lines resulting from the absorption of the media thus interposed1 and1 after their wave lengths are once determined1 they serve as a precise standard to which the stellar lines may be referred4 ,the absorption lines of the terrestrial atmosphere would form the best standard for this purpose if those which are sufficiently fine can be photographed4 #f4 ,wave ,lengths4--,the determination of the wave lengths of the lines in the stellar spectra will form an important part of the work which has not yet been begun4 ,the approximate wave lengths can readily be found from a comparison with the solar spectrum1 a sufficient number of solar lines being present in most stellar spectra4 ,if1 then1 satisfactory results are obtained in the preceding investigation1 the motion of the stars can probably be determined with a high degree of precision4 ,the identification of the lines with those of terrestrial substances will of course form a part of the work1 but the details will be considered subsequently4 ,from the above statement it will be seen that photographic apparatus has been furnished on a scale unequaled elsewhere4 ,but what is more important1 ,mrs4 ,draper has not only provided the means for keeping these instruments actively employed1 several of them during the whole of every clear night1 but also of reducing the results by a considerable force of computers1 and of publishing them in a suitable form4 ,a field of work of great extent and promise is open1 and there seems to be an opportunity to erect to the name of ,dr4 ,henry ,draper a memorial such as heretofore no astronomer has received4 ,one cannot but hope that such an example may be imitated in other departments of astronomy1 and that hereafter other names may be commemorated1 not by a needless duplication of unsupported observatories1 but by the more lasting monuments of useful work accomplished4 ,,edward ,c4 ,,pickering1 ,director of ,harvard ,college ,observatory4 ,cambridge1 ,mass41 ,u4,s4,a41 ,march #a1 #ahhg4 99 99 99 99 99 ,,the ,,winner ,,of ,,the ,,derby4 ,the dark bay colt ,merry ,hampton had never run in public before winning the ,derby on the #beth of ,may last4 ,this colt1 by ,hampton out of ,doll ,tear-sheet1 was one of ,mr4 ,crowther ,harrison's draught of yearlings sent up to the ,doncaster sales in #ahhe1 and fell to the bid of ,mr4 ,t4 ,spence1 acting for ,mr4 ,abingdon1 for #c1ajj guineas4 ,the ,oaks1 on ,may #bg1 was won by a daughter of the same sire4 ,merry ,hampton is to compete for the ,grand ,prize of ,paris and for the ,st4 ,leger4 ,he has also liabilities in the ,thirty-ninth ,triennial and ,grand ,duke ,michael stakes at ,newmarket1 ,first ,october2 ,newmarket ,derby at the ,second ,october2 ,ascot ,derby and ,twenty-fifth ,new ,biennial2 ,drawing-room stakes at ,goodwood2 ,great ,international ,breeders' ,foal stakes at ,kempton ,park1 ,august2 ,north ,derby at ,newcastle1 ,summer2 ,st4 ,george stakes at ,liverpool1 ,july2 ,bickerstaffe stakes and ,st4 ,leger at ,liverpool1 ,august2 ,midland ,derby stakes at ,leicester1 ,july2 and ,ebor ,st4 ,leger at ,york1 ,august2 in addition to the following races in #ahhh3 ,champion stakes at ,newmarket1 ,second ,october2 ,rous ,memorial and ,hardwicke stakes at ,ascot1 and ,eclipse stakes at ,sandown ,park1 ,second ,summer4 ,merry ,hampton's name also appears in the ,kempton ,park ,royal stakes of #aj1jjj sovereigns at the ,spring ,meeting of #ahhi4--;,ill4 ,london ,news4 ,illustration3 ,,merry ,,hampton4 ,,the ,,winner ,,of ,,the ,,derby1 #ahhg4 99 99 99 99 99 ,,the ,,falls ,,of ,,gairsoppa4 ,at the extreme south of the presidency of ,bombay1 separating the district of ,kanara from the territory of ,mysore1 are the too little known ,falls of ,gairsoppa4 ,far higher than ,niagara1 four distinct divisions of the river ,shiravatti 7traditionally created by a cleft made by the arrow of the great god ,rama7 fall over a precipice of gneiss rock into an abyss eight hundred feet below4 ,each of these cataracts differs in type of flow4 ,the ,rajah1 eight hundred and thirty feet1 and at a breadth of fifty-six1 shoots silent and sheer over an uplifted lip of rock in the bed of the stream1 casting a dark shadow behind him when faced by the sun2 the ,roarer makes noise enough in its headlong rush to vibrate the strong1 stone-built travelers' bungalow on the heights above2 the ,rocket is straight in descent1 and1 as a commentator has already remarked1 as much like a rocket as anything else2 and ,la ,dame ,blanche1 a triptych of rhythmical flow1 spreads a dainty1 silky1 sheen of white1 whispering1 glistening1 softly falling water over a slightly shelving width of rock1 touched here and there with prismatic color and strong light4 ,illustration3 ,,the ,,falls ,,of ,,gairsoppa1 ,,between ,,kanara ,,and ,,mysore1 ,,bombay ,,presidency1 ,,india ,the ,falls ,from ,below4 ,the ,falls ,from ,above4 ,at the bottom of the chasm1 seven hundred feet across1 and stretching over a muddy1 turbulent1 seething cauldron of spray1 a brilliantly distinct rainbow in the full light of day may be seen with its scarcely less glorious reflection1 dazzlingly beautiful4 ,in these regions #baj inches of rain is an average downpour for the monsoon between ,may and ,october1 the heaviest fall being generally in ,july4 ,the cataracts then become frequently confluent1 though not more picturesque4 ,they are then too difficult of access1 and the whole district is very malarious4 ,december and ,january are the best months for travelers1 before the dry season fairly sets in again1 during which there is but little water1 even insufficient to form four distinct falls4 ,the best route to them is from ,bombay to ,honaurre by sea1 via ,kawai1 and on to ,old ,gairsoppa by river boat and palanquin to the ,jog1 as the special points of interest 7the ,falls7 are called by the ,kanarese4 ,to the enthusiastic shikari1 however1 the way from ,hubli 7on the ,southern ,mahratta ,railway1 easily reached by ,g4,i4,p4 line from ,bombay71 taking him1 as it does1 through the very happiest hunting grounds of the presidency1 where all game1 small and large1 abounds1 will have attraction enough2 and at ,giddapur1 the last stage1 within twelve miles of the ,falls1 there is a courteous ,english-speaking native magistrate1 willing and able to help the traveler on his way4 ,our engravings are from drawings by ,mr4 ,j4,e4 ,page1 ,c4,e4--,london ,graphic4 99 99 99 99 99 ,,sponges4 ,as the last of a course of lectures upon ,recent ,scientific ,researches in ,australasia1 ,dr4 ,r4 ,von ,ledenfeld lately delivered a lecture at the ,royal ,institution1 upon ,recent ,additions to our ,knowledge of ,sponges4 ,the lecturer did not confine himself to the sponges of ,australia alone1 but gave a resume of the results of recent investigations on sponges1 together with several new interesting details observed more especially in studying the growth of ,australian sponges4 ,with a passing reference to some peculiarities of the lower marine animals of the ,australian coast1 ,dr4 ,ledenfeld remarked upon the preponderance of sponges over other forms of marine life in that part of the world4 ,it has long been a point of discussion as to whether sponges belong to the vegetable or animal kingdom1 but naturalists are now generally agreed in regarding them as animals1 a conclusion1 the lecturer remarked1 that ,aristotle had also arrived at4 ,sponges grow in a variety of more or less irregular shapes1 but it has been observed that the most regular structures occur in the calcareous species4 ,as to color1 ,dr4 ,ledenfeld remarked that some of the ,australian sponges are of exceptionally brilliant hues1 while others range from the black of the common sponge 7,euspongia officinalis7 to a pure white4 ,also1 it may be remarked1 the sponges growing in deep water are of less decided color and more elastic in character than those living in shallow water1 and from the last named quality are more valuable in commerce4 ,the irregular honeycombed appearance of the sponge is due to a most complicated canal system1 consisting of a series of chambers through which the water is drawn by the animal in always the same direction4 ,the inhalent pores are very minute1 and open into small subdermal cavities which communicate by means of interradial tubes with the ciliated chambers1 the latter being very small ramifications of the interradial channels1 and in them the movement causing the current of water is maintained4 ,from hence all faecal and other matter is discharged through the oscula1 the larger openings observed on the surface of the sponge4 ,dr4 ,ledenfeld showed the different parts of sponges by means of microscopic slides thrown on to a screen1 and also the shape and arrangement of the chambers in different species4 ,the ciliated chambers especially attracted attention4 ,they are very small and circular1 and the interior is clothed with cells very similar to the cilia cells in higher animal life4 ,these cells are arranged around the ciliated chambers in the form of a collar1 and from each cell flagella protrude1 which are in continual motion4 ,these flagella1 like bats' wings1 are capable of being bent in only one direction1 so that1 in the course of their pendulum-like motion1 in the movement one way the flagella are bent1 while in the return movement they remain stiff1 thus causing a current of water always flowing in one and the same direction4 ,these ciliated chambers are easily detected in the sponge by means of a microscope1 as they appear more highly colored4 ,after the lecturer had thus given a general outline of the structure of the sponge1 he drew attention to the character of its food and its method of digestion4 ,it is not known exactly what the sponge lives upon1 but if upon other animals they must be necessarily very small1 owing to the size of its inhalent pores4 ,the sponge1 like the tape-worm1 has no stomach1 but must absorb its food through the outer skin from matter in a soluble state1 similarly to the roots of trees4 ,this process of absorption is probably accomplished in the interradial or ciliated chambers1 more probably in the former1 as the latter are generally considered excretory in function4 ,lime or silica must also be absorbed from the water by most sponges in order to make up the skeleton4 ,the skeleton of calcareous sponges consists of a number of spicules composed of carbonate of lime4 ,these spicules are of very varied though regular shape1 but ordinarily assume a rod-like needle shape or else a stellate form4 ,in silicious sponges the spicules are composed of silica1 and are generally deposited around axial rods in concentric layers4 ,the spicules are joined together and cemented by a body that has been named spongin1 which has much the same chemical composition as silk1 and1 like silk1 is very elastic4 ,in some varieties of sponges1 especially in the kinds which come into the market1 the skeleton is almost entirely composed of fibers of pure spongin4 ,these fibers are so close together as to draw up water by capillary action1 and1 indeed1 a great deal in the value of a sponge depends upon the fineness and tenuity of these fibers4 ,dr4 ,ledenfeld again illustrated this stage of his lecture by means of a number of microscopic slides in which the variety of shape and size of these spicules and spongin fibers were shown4 ,the spicules are some crutch-like1 others spined or echinated1 while the deep-sea sponges appear to grow long thick spicules1 which attach the sponge to the ground by means of grapnel-like ends4 ,in some cases the skeleton seems to be more or less replaced by sand1 the small grains of which are cemented together by the spongin4 ,dr4 ,ledenfeld then drew attention to the presence of more highly developed organs in the sponge4 ,muscles pervade the whole tissue of the sponge1 but are found more particularly in the superficial parts4 ,one set of muscles affect the size of the inhalent pores1 causing them to contract or expand1 while another set are able to close the pores altogether1 thus acting as a protection from the attack of an enemy4 ,all these muscles are composed of spindle shaped cells1 which are capable of spasmodic motion1 but recently in an ,australian sponge1 the ,euspongia canalicula1 the lecturer said he had observed muscles approaching very nearly in character those of the human frame4 ,that sponges have nerves is a discovery of recent date by a member of the ,royal ,microscopical ,society4 ,dr4 ,ledenfeld also about the same time found indications of the presence of a nervous system1 but the form in which he observed the nerves at first apparently differed from those observed simultaneously4 ,this difference1 however1 he afterward found to be due to the manner in which the section had been prepared for observation4 ,the nerves consist of two cells at the base of a cone-like projection on the epidermis1 and from each cell a fiber runs to the point of the cone1 besides several others connecting them with the interior of the sponge4 ,it is remarkable that here again ,aristotle has predicted that sponges have a nervous system1 basing his statement on the fact that ancient ,greek mariners foretold storms by the alleged contraction of the sponge4 ,the reproductive organs of sponges are also very highly developed1 and both ova and spermatozoa are found throughout the sponge1 though more concentrated in the interior4 ,the ova consist of spherical cells1 while the spermatozoa resemble an arrow-head in shape4 ,it has not yet been ascertained whether two sexes exist in sponges1 or whether the ova and spermatozoa are produced at different periods by the same sponge4 ,when the embryo has become partly developed1 it detaches itself from the parent sponge1 and1 issuing from the oscula1 propels itself through the water by means of a number of flagella4 ,silicious spicules next appear in its structure1 and it then attaches itself to a rock and assumes its mature form4 ,sponges are most numerous in the waters of the temperate and sub-tropical zones1 and the salt-water varieties are by far more numerous than the fresh water4 ,thus1 while there are not more than ten fresh-water species known1 ,dr4 ,ledenfeld remarked that about one thousand species of salt-water sponges had been recognized4 ,each species of the salt-water sponge is1 however1 generally found only in limited areas1 and very few1 all of which inhabit deep water1 are cosmopolitan4 ,this is the more remarkable as ,dr4 ,ledenfeld asserts that all the sponges inhabiting the rivers of ,australia are identical with the fresh-water sponges of ,europe1 and in order to explain this fact he put forward a rather interesting theory4 ,he assumes that sponge life in rivers has been originally generated by the introduction of a single1 or at most two or three germs by means of aquatic birds4 ,the inbreeding consequent upon this paucity of sponge life has produced a certain fixity of character in fresh-water sponges1 and is in direct opposition to the effects of hybridization in the salt-water sponges1 by which they have acquired the capacity of adapting themselves to local circumstances4 99 99 99 99 99 ,,herbet',s ,,tepid ,,douche4 ,keeping the body clean is indispensable for the preservation of good health1 through obtaining an operation of the skin and expelling matter whose presence aids in the development of diseases4 ,it is unfortunately necessary to say that1 considering the population as a whole1 the proportion of those who take baths is very small4 ,this is due to the fact that the habit of cleanliness1 which should become a necessity1 has not been early inculcated in every individual2 and the reason that this complement to education is not realized is because the means of satisfying its exigencies are usually wanting4 ,we shall not speak of the improved processes that are used solely by the rich or well-to-do1 as these become impracticable where it is a question of the working classes or of large masses of individuals4 ,it is1 in fact1 the last named category that interests us1 and we are convinced that if we get young soldiers and children to hold dirtiness in horror1 we shall be sure that they will later on take care of their bodies themselves4 ,the most tempting solution of this question of washing seems to be found in the use of large pools of running tepid water2 but such a process is too costly for general use1 and the most economical one1 without doubt1 consists in giving tepid douches4 ,illustration3 ,,tepid ,,water ,,douche ,to our knowledge1 the only apparatus in this line that has been devised was exhibited last year at the exhibition of hygiene in the ,loban barracks4 ,it has been used daily for six years in several garrisons1 and therefore has the sanction of practice4 ,this apparatus1 which is due to ,mr4 ,herbet1 consists of a steam boiler and of an ejector fixed to a reservoir of water and provided with a rubber tube to which a nozzle is attached4 ,the steam generated in the boiler passes into the ejector1 sucks up the water and forces it out in a tepid state4 ,the apparatus thus established did not sufficiently fulfill the purpose for which it was designed4 ,it was necessary to have a means of varying the temperature of the water projected1 according to the season and temperature of the air1 to have an instantaneous and simple method of regulating the apparatus1 that could be understood by any operator1 and to have the apparatus under the control of the person holding the nozzle4 ,these difficulties have been solved very simply by causing the orifice of the nozzle to vary4 ,this nozzle1 from whence the jet escapes1 is formed of rings that screw together4 ,when the nozzle is entire1 the jet escapes at a temperature of say #dj4 ,when the first ring is unscrewed1 the water will make its exit at a temperature of #ch4 ,in order to lower the temperature still further1 it is only necessary to unscrew the other rings in succession1 until the desired temperature has been obtained4 ,as it is1 the apparatus is rendering great services where it has been introduced2 for example1 at ,besancon and ,belfort4 ,it serves1 in fact1 for an entire garrison1 while that before1 the washing was done in each regiment1 thus requiring the use of much space and causing much loss of time4 ,eight men are washed at once for five minutes1 say #if men per hour4 ,every minute the men turn right about face1 and when they are in file each rubs the other's back4 ,twenty-two pounds of coal and #bfj gallons of water are consumed per hour1 and the boiler produces #acj lb4 of steam4--,le ,genie ,civil4 99 99 99 99 99 ,,how ,,to ,,make ,a ,,star ,,finder4 ,being all of wood1 it is easily made by any one who can use a few tools1 the only bit of lathe work necessary being the turned shoulder1 ,k1 of polar axis4 ,a is the baseboard1 #i in4 by #e in41 near each corner of which is inserted an ordinary wood screw1 ,s ,s1 for the purpose of leveling the base1 to which two side pieces are nailed1 having the angle1 x1 equal to the co-latitude of the place4 ,on to these side pieces is fastened another board1 on which is marked the hour circle1 ,f4 ,through this board passes the lower end of the polar axis1 having a shoulder turned up on it at ,k1 and is secured by a wooden collar and pin underneath4 ,on to the upper part of the polar axis is fastened the declination circle1 ,c1 #e in4 diameter1 made of in4 baywood1 having the outer rim of a thin compass card divided into degrees pasted on to it4 ,the hour circle1 ,f1 is half of a similar card1 with the hours painted underneath1 and divided to #bj minutes4 ,g is the hour index4 ,d is a straight wooden pointer1 #ab in4 long1 having a piece of brass tube1 ,e1 attached1 and a small opening at ,j1 into which is fixed the point of a common pin by which to set the pointer in declination4 ,h is a nut to clamp pointer in position4 ,by this simple toy affair ,i have often picked up the planet ,venus at midday when visible to the naked eye4--,t4,r4 ,clapham in ,english ,mechanic4 ,illustration3 ,a ,,star ,,finder4 99 99 99 99 99 ,the best mode of finding or tracing trichinae in pork by means of a microscope is the following3 ,cut a very thin longitudinal slice of the muscle by means of a very sharp knife or razor4 ,press it between two glass slips1 and examine by transmitted light1 ,the coiled trichinae may be readily distinguished from the muscle fiber4 99 99 99 99 99 ,,the ,,scientific ,,american ,,supplement4 ,,published ,,weekly4 ,,terms ,,of ,,subscription1 #e ,a ,,year4 ,sent by mail1 postage prepaid1 to subscribers in any part of the ,united ,states or ,canada4 ,six dollars a year1 sent1 prepaid1 to any foreign country4 ,all the back numbers of ,,the ,,supplement1 from the commencement1 ,january #a1 #ahgf1 can be had4 ,price1 #aj cents each4 ,all the back volumes of ,,the ,,supplement can likewise be supplied4 ,two volumes are issued yearly4 ,price of each volume1 #b4ej1 stitched in paper1 or #c4ej1 bound in stiff covers4 ,,combined ,,rates--,one copy of ,,scientific ,,american and one copy of ,,scientific ,,american ,,supplement1 one year1 postpaid1 #g4jj4 ,a liberal discount to booksellers1 news agents1 and canvassers4 ,,munn ,,co41 ,,publishers1 #cfa ,,broadway1 ,,new ,,york1 ,n4,y4 99 99 99 99 99 ,,patents4 ,in connection with the ,,scientific ,,american1 ,messrs4 ,,munn ,co4 are ,solicitors of ,american and ,foreign ,patents1 have had #db years' experience1 and now have the largest establishment in the world4 ,patents are obtained on the best terms4 ,a special notice is made in the ,,scientific ,,american of all ,inventions patented through this ,agency1 with the name and residence of the ,patentee4 ,by the immense circulation thus given1 public attention is directed to the merits of the new patent1 and sales or introduction often easily effected4 ,any person who has made a new discovery or invention can ascertain1 free of charge1 whether a patent can probably be obtained1 by writing to ,,munn ,co4 ,we also send free our ,hand ,book about the ,patent ,laws1 ,patents1 ,caveats1 ,trade ,marks1 their costs1 and how procured4 ,address ,,munn ,,co41 #cfa ,,broadway1 ,,new ,,york4 ,branch ,office1 #fbb and #fbd ,f ,st41 ,washington1 ,d4,c4 ,,the ,,scientific ,,american ,architects and ,builders ,edition4 #b4ej a ,year4 ,single ,copies1 #be ,cents4 ,this is a ,special ,edition of ,,the ,,scientific ,,american1 issued monthly--on the first day of the month4 ,each number contains about forty large quarto pages1 equal to about two hundred ordinary book pages1 forming1 practically1 a large and splendid ,,magazine ,,of ,,architecture1 richly adorned with elegant plates in colors and with fine engravings2 illustrating the most interesting examples of modern ,architectural ,construction and allied subjects4 ,a special feature is the presentation in each number of a variety of the latest and best plans for private residences1 city and country1 including those of very moderate cost as well as the more expensive4 ,drawings in perspective and in color are given1 together with full ,plans1 ,specifications1 ,costs1 ,bills of ,estimate1 and ,sheets of ,details4 ,no other building paper contains so many plans1 details1 and specifications regularly presented as the ,,scientific ,,american4 ,hundreds of dwellings have already been erected on the various plans we have issued during the past year1 and many others are in process of construction4 ,architects1 ,builders1 and ,owners will find this work valuable in furnishing fresh and useful suggestions4 ,all who contemplate building or improving homes1 or erecting structures of any kind1 have before them in this work an almost endless series of the latest and best examples from which to make selections1 thus saving time and money4 ,many other subjects1 including ,sewerage1 ,piping1 ,lighting1 ,warming1 ,ventilating1 ,decorating1 ,laying out of ,grounds1 etc41 are illustrated4 ,an extensive ,compendium of ,manufacturers ,announcements is also given1 in which the most reliable and approved ,building ,materials1 ,goods1 ,machines1 ,tools1 and ,appliances are described and illustrated1 with addresses of the makers1 etc4 ,the fullness1 richness1 cheapness1 and convenience of this work have won for it the ,,largest ,,circulation ,,of any ,architectural publication in the world4 ,,munn ,,co41 ,publishers1 #cfa ,broadway1 ,new ,york4 ,a ,catalogue of valuable books on ,architecture1 ,building1 ,carpentry1 ,masonry1 ,heating1 ,warming1 ,lighting1 ,ventilation1 and all branches of industry pertaining to the art of ,building1 is supplied free of charge1 sent to any address4 99 99 99 99 99 ,,building ,,plans and ,,specifications4 ,in connection with the publication of the ,,building ,,edition of the ,,scientific ,,american1 ,messrs4 ,munn ,co1 furnish plans and specifications for buildings of every kind1 including ,churches1 ,schools1 ,stores1 ,dwellings1 ,carriage ,houses1 ,barns1 etc4 ,in this work they are assisted by able and experienced architects4 ,full plans1 details1 and specifications for the various buildings illustrated in this paper can be supplied4 ,those who contemplate building1 or who wish to alter1 improve1 extend1 or add to existing buildings1 whether wings1 porches1 bay windows1 or attic rooms1 are invited to communicate with the undersigned4 ,our work extends to all parts of the country4 ,estimates1 plans1 and drawings1 promptly prepared4 ,terms moderate4 ,address ,,munn ,,co41 #cfa ,broadway1 ,new ,york4