The Iron Age 1892-09-01: Vol 50

‘THE THURSDAY, SEPTEMBER ], 1892, MAKING GREAT GUNS. Shrinking On Jackets and Hoops. |of 1 tube, 1 jacket and 27 hoops, arranged as shown in Fig. 11. The first step is to place the jacket on the tube, after which the hoops follow in regular order. The care and skill called for by this work will One of the most interesting operations | be appreciated when we state that neither connected with the building of breech-|the jacket nor either one of the hoops will IRON AGE lated compression. It is evident that a very slight error in either the diameter of the encircling part or of its seat, we may call it, will destroy these conditions and produce a gun not having the greatest strength, and, in fact, one in which the stresses will not be known and cannot be Fig. 1.—Gun, Carried by Two Cranes, Entering Shrinkage Pit. MAKING GREAT GUNS. loading rifles of large caliber is the|go on the place intended to receive it | ascertained. It is for this reason that all shrinking of the jackets and hoops on the| until it has been heated to a certain tem-| boring and turning operations are per- tube, the latter serving as a foundation| perature, the expansion then resulting upon which the others are built up. The| permitting it to slip into place. When 10-inch gun, which we propose to follow | the part fitted on has been cooled it should formed so accurately. Through the kind courtesy of the officers of the Ordnance Department of the United through the various stages of work per-| be under a predetermined tensile strain, | States Army, we were recently granted the formed at the shrinkage pit, is composed|and the part it encircles under a calcu-| privi'ege of seeing this work as carried on | a ‘ U ‘4 f & i i f ig Yd Lt hdl BLL A AE >) WR) PHY >) Wey ie Wy) VES ie a WwW ) Sa eee = “~~ 4 a 2) BD. he —_ P) ssp # Fr; — ao - — ~Se . : 2) aaa Tak . ee 366 at the Watervliet Arsenal, West Troy, N. Y., and of taking such photographs as Were necessary in order to show the various steps. An article of this kind naturally divides itself into two parts, the first being descriptive of the work performed at the shrinkage pit and including the method of handling the gun, placing it in the pit, heating and putting the jacket and hoops on the gun, and the final removal of the gun from the pit. This portion of the article is in no sense technical, the second part being devoted to the specifications and detailing the requirements the steel must conform with, the tensile and com- pression strains, gauging, and final testing. Description of the Parts. The tube for the 10-inch gun, as it is received from the Bethlehem Iron Works, weighs 18,945 pounds, and has been rough turned and bored. This tube is en- veloped by the jacket and by the C hoops. The jacket projects to the rear of the tube 16.2 inches, and is in contact with the tube for a length of 120.8 inches. The C hoops extend from the front of the jacket to the muzzle of the gun, a distance of 206.25 inches, the C' hoop being in con- tact with the jacket, and the hoops suc- ceeding each other in the order of their numbers, C* being the muzzle hoop. Hoops C* to C* are stepped—that is, the interior of each of these hoops has two diameters differing from each by from 0.25 to 0.65 inch. The tube has corresponding di- ameters and steps, and therefore the diam- eter of the tube is gradually reduced from 18 20 under the jacket to 14.50 at the muzzle. The thickness of the tube over the powder chamber is 3.2 inches, and its maximum thickness in the front of the shot chamber is 4.1 inches. Its thickness at the muzzle is 2.25 inches. The four D hoops extend in the order of their numbers from a shoulder on the jacket toward the muzzle, a distance of 83.75 inches. The D' hoop has a recess in its interior which fits over corresponding shoulders on the front of the jacket and the rear of the C' hoop; the D' hoop thus locks the C' hoop to the jacket. The fill- ing ring is a split ring which is placed be- tween the front shoulder of the jacket and the hoop to allow for longitudinal expan- sion in heating and shrinking on the D! hoop. This D' hoop envelops the front end of the jacket and part of C' hoop. The A hoops extend in the order of their numbers from a shoulder near the middle of D' hoop to the rear of the gun, their total length being 138.75 inches. The B hoops extend in the order of their num- bers from the shoulder on the A' hoop to the rear of the gun. The exact position of all these parts will be seen by consulting the longitudinal section of the gun, Fig. 11, in which it will be noticed that hoops D', D? and C’ are more heavily shaded than the other parts. This is done because these hoops were being put in position when the accompanying photographs were taken. This drawing also gives all the principal dimensions of the gun as a whole, together with the lengths and diameters of the jacket and hoops. The first work done on the tube is the turning of that portion destined to receive the jacket to a diameter of 18.2 inches, The tube is then removed from the lathe and by means of traveling cranes taken to the pit, in which it is placed muzzle end down. The jacket, which has been pre- viously bored to the proper diameter to fit the tube, and which for several hours bas been heating in the furnace from which it is just being removed, as shown in Fig. 5, is then lowered down over the tube. After having been cooled, the tube with its jacket is taken back to the lathe and turned in order to receive the next hoops. Of course the position of the gun in the pit—that is, whether it is muzzle or breech end up—depends upon the hoops to be put THE IRON AGE. September 1, 1899 . un | a adenpen “Hi i | ae | | — — | ee Ss Fig. 3.—Gun Being Lowered into Pit, MAKING GREAT GUNS. September 1, 1892 THE IRON AGE. 367 on. In general it may be stated that all|and the lathes, and also makes necessary a| to be placed muzzle up, is at the muzzle end the C and D hoops are put on with muzzle| very thorough and extended system of|of the gun, the breech end of the gun up; the others, with muzzle down. Only | gauging in order to insure accuracy in the| being encircled by a band formed with two or three hoops can be put on at the | sizes. two hooks. Two overhead traveling Fig. 6.—D' Hoop Being Lowered Over Gun. cranes are now brought into service, one attaching its lifting chains to the band around the breech and the other its chains to the link at the muzzle. The cranes then move forward until the breech end of the gun is over the shrinkage pit, when the crane carrying that end begins to lower, the other end gradually approaching it until finally, as shown in Fig. 2, the gun is carried wholly by the crane having hold of the muzzle, the other crane being re- lieved of its load as soon as the gun has assumed a vertical position. The gun is then lowered, as shown in Fig. 3, into the pit, and after it has been securely clamped in its upright position the last crane is un- hooked. In removing the gun from the pit the same operation precisely is gone through with, though, of course, in reverse order. ny a zy ti wy iG - x Shrinkage Pit. The perspective engravings, and also the sectional and plan views, Figs. 8, 9 and 10, convey a good idea of the general ar- rangement of the shrinkage pit. This con- sists merely of a rectangular hole sunk in the center of the shop and having a depth sufficient to take in the longest gun it is proposed to build and not have it extend above the floor level. At one side of the pit are two furnaces, in one of which, B, three or four hoops can be heated, and in the other of which, A, the jacket can be heated. The hoop furnace is rectangular in plan, while the jacket furnace is circu- Fig. 5.—Jacket for 12-Inch Gun Being Raised from Furnace. lar. An important point in the heating operation is to maintain a uniform temper- ature, and at the same time to keep away from the part heated the products of com- bustion, which might have a hurtful effect upon it. For this reason the furnaces con- sist of a mere shell of iron, around which circulate the products of combustion, pass- OZ. “a Se es bebe ie Be) BD) HD) DH) )Y>) Wa ao (For the Photograph from which this Engraving was made we are Indebted to Mr. Anthony Victorin.) MAKING GREAT GUNS. Placing the Gun in the Pit. same time, and after each shrinkage oper- ation the gun must be taken back to the lathe, turned for the next set of hoops and brought to the pit in order to receive them. This makes it necessary to carry the gun several times to and fro between the pit The first step toward placing the gun in the pit is to pass through the bore a steel rod 3 or 4 inches in diameter and provided with a link at one end and a nut at the opposite end. The link, when the gun is ing from the fire box around these shells and finally entering the boiler smoke stack. In this way the jacket and hoops are heated solely by radiation, and the temper- ature can be regulated to a nicety, and at the same time it is not possible to injure a “Sa ;im aor & ei ty iP iy 368 September 1, 1892 the metal by reason of any chemical change. Handling the Jacket and Hoops. Both the jacket and hoops, before being placed in the heating furnace, are encircled by a band placed near one end and pro- vided with two hooks to receive rings car- ried by the hoisting chain of the crane, as | shown in Figs. 4,5 and 6. When it is thought that the jacket has been heated to the proper temperature, the crane is brought into play, its chain hooked on and the jacket lifted from its furnace. The inspector then passes the gauge into the interior, to ascertain by actual measure- ment whether the expansion has been suf- ficient to permit of the jacket passing freely down over the tube. If in his judgment it will not go down, it is re- placed in the furnace and heated to a higher temperature. The same thing ex- actly takes place with all the hoops. No guess work is allowed; and unless the ex pansion has been surely sufficient to permit of the free passage of the part it is heated still further. The absolute necessity of this will be understood when we state that a slight mistake might result in the loss of thou- sands of dollars. The tube for the 10 inch gun weighs 18,945 pounds, the jacket weighs 18,115 pounds, and the cost, de- livered at the arsenal, is from 27 to 33 cents a pound ; and as the work done up to this stage is about the same on both, they have an equal money value. teresting point would come up if for any reason, due to warping of the jacket or to a mistake in calculations of the size of the tube or of the bore of the jacket, it should fail to reach its proper seat; the question then would be whether to destroy the tube orthe jacket. In other words, the cost of both being the same, whether to bore the tube out of the jacket or to turn the jacket off of the tube. Of course, if one of tbe hoops should fail to reach its proper posi- tion for any reason the hoop would be turned off, since the cost then would be Fig. 8.—Section of Shrinkage Pit. An in- | a an i | i ie ) iy Nok vor wc gat) WA See ere > b | ' aI c | iF A | ee ™ 7 1 b> hy 1 fi TG i + | ] ' + 7 } Hie itu i \ | ; toca a » \ c =) Loot \ V5 | how [ \ Tee ieee x 4 < > = - _ = een ot * Z L tT hg 1 |] GY g | | Y 7 TA: | i} || 1} if 1} | ig | |e. | | Ly “Y | ] 7" | 1] eal || | 4 pe ee ogy ee l i ' ; ' . mS | { be 1} j it Z Z | ty Mi, Z it ly : 4 ! x 4 a | | i , G7 A yf (| UV} Z, i Yj LY HOW WW “ih il i ts Ys <5 YY E 4 . | tj; LILO eT Yi YY orldej g ty CLL LAS Ahh Sd déddddad id, Fig. 9.—Section of Shrinkage Pit at Right Angles to Fig. 8. MAKING GREAT GUNS. September 1, 1892 too greatly in favor of the gun, as far as it had gone. We might add in paren- thesis that up to this time no difficulty of this kind has been experienced. In every case the jackets and hoops have gone to their proper position, so that a discus- sion of what would be done in case of a slip might seem to be premature. Cooling. Encircling the gun as it stands in the pit is an iron pipe, provided in its inner side with rows of holes, and suitably con- nected with a water supply, in order that jets of water may be played upon the hoop after it has been placed in position. In the case of the D' hoop, which is shown going down over the gun in Figs. 4 and 6, and the position of which is shown in Fig. 11, the water is first sprayed upon the lower edge, the object being to con- tract this portion by cooling and make it grip the end of the jacket over which it passes for a short distance, and then to raise the water circle, gradually cooling from the bottom up. The first binding takes place at the lower edge of the hoop, and any subsequent movement is from the upper end downward as the metal cools and contracts. It is the same way with D* hoop and C’ hoop. After the hoops THE IRON AGE. gun contains, without any exaggeration, thousands of measurements which repre- sent every stroke of work which has been done upon that gun, and show the effect. | Inside gauging is done by means of the ordinary star gauge, working upon the wedge principle. These measurements | serve one most essential purpose. Take as | an illustration the D' hoop. If the seat destined for this hoop and the hoop! itself have been worked to the proper sizes, the hoop will exert a certain strain upon the jacket and tube it encircles. This strain will produce a known compression | upon these parts, and therefore a certain reduction in the diameter of the bore will result. If this reduction in diameter is ex- cessive, it is evident that the hoop has been bored too small, and is therefore under too great a tensile strain. On the contrary, if the bore has not been reduced in diameter up to the limit, it shows that the hoop has been bored to too great a diameter and is not under the tensile strain it should be, and therefore has not brought the other members under a proper degree of compression. In the case of the jacket especially, and that portion of the tube destined to receive it, it is most essential that both should be truly cylindrical. The jacket is several Fia. 10.—Plan of Shrinkage Pit. MAKING have been cooled sufficiently by the jet of water, the gun is removed from the pit and generally left over night, in order that the parts may become all of one tempera- ture, and then taken back to the lathe for other operations of turning. But before being taken to the lathe every inch of the bore likely to be at all affected by the three hoops just shrunk on is carefully measured by means of a star gauge. In order to show the tremendous pressure exerted by these hoops we may mention that the hoops D' D’, although acting through the metal in the tubp, the jacket and hoops C' C?, produced a maxi- mum reduction in the diameter of the bore of 0.0065 inch The Log Book of the Gun, A record of every gun is kept in what we have termed a log book of the gun. As we have before said, every step in the manufacture is accurately measured, and there must not be a variation of more than a quarter of a thousandth from a prescribed dimension. In turning the tube and bor- ing the jacket to fit, the endeavor is to get as fine work as possible and as true sur- faces free from tool marks. In boring the tube for the hoops, and in boring the hoops themselves, this is not aimed at, since a certain degree of roughness is considered an advantage. Nevertheless, the measure- ments must be accurate, and for this reeson we find that the log book of a completed GREAT GUNS. feet in length, and even when heated it is but the fraction of an inch larger in di- ameter than the tube, so that it would only require a very slight variation from a true cylinder in order to prevent its pas- sage over the tube. It is, therefore, | necessary in this case to make sure not| only that the diameters at each inch of the length are correct, but also that the tube and bore of the jacket are perfectly cylin- drical. Physical Qualities of the Steel. | We can, perhaps, convey the clearest idea of the physical qualities of the steel | by condensing the report of the Inspector of Ordnance at the Bethlehem Iron Works. From tabulated statements presented in the report of the Chief of Ordnance for the year 1890, we find that tests of tan- gential specimens from the ends of tubes for 8-inch breech-loading rifles showed tensile strength per square inch of from 84,400 pounds up to 100,000 pounds, elongation from 20 to 25 per cent., and reduction in area after rupture from 30 to 47 per cent. Tests of specimens from the jackets showed tensile strength per square inch of from 90,000 pounds to 108,000 pounds, elongation from 20 to 23 per cent. and reduction in area after rupture from 30 to 44.5 per cent. In the tests of speci- mens taken from the inside, outside and middle of trunnion hoops and plain hoops, the tensile strength in only a very few 343.25 length of Gun 347.25 length over all 50 79 is 103.0 Of 50.75 18,25 25 9 8.50 2 20.9 41.75 >« 21 ' It k5.75 | 30,25 yA ~< 18.0 > ' 18.0 21,25 ~ SS SS SS SS = Ss SLLg SSS SSS S S SS SS = titles 3 > as s > a . ys 7 Y ~ ea A ATI Weytuvapag . as VHGA Z 3: 5 ZZ TZ / 5 % : Lk Z , SSS | SS Fig. 11.—Longitudinal; Section of 10-Inch Breech-loading Rifle, Ree neta $ é By} >) WWE yy (ILS AGL Sep SNR awe PD) B) ‘ Val DA ee Se ee — ws wipe RA be ~~. ee = 7 LE! ms ee nee 6 - ‘omer 4 ey by) B) ee ae ot 2 oP 7272 = — —_——o eee 370 cases fell below 100,000 pounds to the square inch. Shrinkages, The shrinkages given in the accompany- ing table are to be understood as differ- ences of diameter simply. In general, the outer diameters of the hoops, except the trunnion hoop, which is finished com- pletely, are rough finished to about 0.10 inch in excess of the prescribed diame- ters preparatory to assemblage. As the shrinkage in no case exceeds 0.045 inch, this surplus will leave sufficient metal for the shrinkage finish. Shrinkages Used. FIRST SHRINKAGE, ! ye 38 7 rE: Section a Se c= Ez of gun. Sa os = os ~ “4k =a “4s 0. Z > > Inch, Inch. Inch. Inch. Il. : 0.006 0.00384875 —0.008 —4).00R25625 BERG ccnase 0.010 0.000564 —0.008 —0.000436 i 0.010 0.008875 —0.008 —).001125 is kins 0.010 0.010162 —0.008 +0.000162 Mathes 0.010 :0.0100857 —0.008 +0.000086 5 { 0.0100.00950 e | —0.00050 VII....... 190.015 0.014416 ¢ —2-8) 0000583 Wssckwes 0.025 0.02466 —0.008 ee » \ 0.0230 0204375 | ) —0.00256 Ix 7 0.0190 018548 5 —8-%8> 9 o00454+- Ts dea 0.018'0.016543 —0.008 —0.00145+- TE Rse nis 6a 0.017:0.014408 —0.008 —0.00259+4- BRM oss 0.015'0.014321 —).008 —0.000679 EE snes 0.014.0.012611 —0.008 —0.00138+ DEW ccccess 0.012 0.0091875 —0.003 —).0028125 * For 3 inches. SECOND SHRINKAGE, | ood 0.042'0.042823 |—,008 !4-0.000823 ee 0.042/0.04300 |—0.003 40,0010 eens I 0.046.0.045134 —0.008 |—0.000866 | 0.046'0.044260 (—0.008 (—0.00174 Wika: 0.046'0.044647 (—0.008 —0.001354+ VI § 0.046 0.04383 | lo uo! —).00217 1 0.048.0.042425 4 . + —).000575 i 0.026) 0.025962 —.008 —0.000088 .j | 0.024/0.022650 —0).003 |\—0.00135 IX. 0.023,0.0204229 —0.003 |—0.00257 THIRD SHRINKAGE. Dans eae 0.080 0 082682 —0.003 |+0.002632 Il. ; 0.044 0.04438 —).008 =+0.00088 i = 0.044 0.045528 —0.008 | 4-0.001523 eb on 0.044 0.045818 —).008 +0.001318 Vv 0.037 0.038426 —).008 +0.0001426 In the above table the values in the column ‘‘actual shrinkage—inch ” are the means of the values of the actual shrink- ages for each section of the gun. The next table gives a summary of the actual final compressions of the bore as measured and the theoretical compressions obtained by formulas: Compressions Due to Shrinkage. Section Calculated Actual Differ- of gun. compression. compression ence, Inch, Inch. Inch. cart 000800 0.00756568 —0.0004382 sin, 0.0126098 0.012166 —() 0004438 BOE wisdse 0.015842 0.014127 —). 0004072 os 0.0121090 0.012000 —(). 0001090 oath 00124808 0.012073 —), 0004073 Oe nalen 0.0091704 0.01067 +0 ,.0004996 Jf ee 0.0106213 0.01096 +4). 0003387 i 0.0109399 0 0108125 —0.00086274 ie 0 OO9ST9S 0.0092109 =—0.0006689 Ded 0.050724 0.0056645 +-0.0005921 PR ax sies 0.0044616 0.0051481 = +-0.0006865 "XII ; 0..0046859 0.0048125 | -++0.0001266 MARAE «oss 0. 0042577 0.004700 == +0.0004423 3 0. 0030998 0.0089342 +0).0008344 Time Required to Heat Jacket and Hoops. The average time of heating the jacket and hoop and required to remove jacket THE IRON AGE. and hoop from the furnace and place them on the gun is given in the next table: ! Average time required to Average time remove jacket of heating and hoops the jacket. and place on gun. H. M.S. M.S. SOOKOF 66 acces.) Bi BE 27 00 17 BOOS ov vcccessee. 2 0 7 2 2 SPR a5 wees soos 2 18 45 1 5 POE. .iciscaceves 2 15 8 1 19 BP OOO 2s ne0css 2 29 8 5 44 *The jacket was put in the furnace when the fire was started. Average Clearances. The average clearances over shrinkage diameters in assembling are here given: | Average clearances over shrink- age diam- Average ex- Tempera- pansion per ture corre- inch of sponding to diameter. expansions. eters. Inch. Tnch. Degrees F. Jacket... 0.056 0.00357 545 C hoops.. 0 032 0.00295 450 D hoops. 0.042 0.00875 572 A hoops. 0.059 0.00377 575 B hcops. *() 085 0.00381 581 DOGS) ki0s. kvicscsas 0 00857 545 *The B hoops were given the additional ex- pansion as they had to be carried from the furnace to the lathe. The Joints Between the Hoops, One of the most noticeable features con- nected with this work was the exceedingly small width of the spaces separating the abutting ends of the hoops. This proved that the ends had been truly faced on the lathe and that the last hoop had been properly seated, and that the cooling spray of water had been applied at the right place. A blunder at any one of these stages would have widened this space and injured the gun. We tried several of these joints, and in not one of them was it possi- ble to insert a thin knife blade even a short distance. Cost. The guns manufactured at Watervliet cost as follows: DS ican denaesek dae ab cd woberaaae £15,646 POR, cc nena sek bake ce eeesadananaenin 30,592 PCRs 5 aos va caes ces ewnhesdsasionaaeee 47,227 As the 8 inch gun weighs 39,674 pounds, the 10 inch 82,664 pounds and the 12-inch 140,578 pounds, each gun of this type and size may be considered as costing about $800 per ton. Personnel, The Watervliet Arsenal, as well as all other Government arsenals, is under the charge of the Ordnance Department, United States Army, Brig.-Gen. D. W. Flagler, stationed at Washington, being Chief of Ordnance. The commanding officer at the arsenal is Lieut.-Col. F. H. Parker, under whom the gun factory has been mostly built up to its present state of completion. He is assisted by the following officers: Capt. C. C. Morrison, acting paymaster, storekeeper, quartermaster and commissary of subsistence of the post, and who acts as recorder of the Board of Ordnance and Fortification in Washington, of which General Schofield is president. Capt. W. B. Gordon has at present im- mediate charge of the gun shops. Capt. F. E. Hobbs has immediate charge of the projectile factory and of making the field gun carriages. Lieut. D. A. Howard, until recently had charge of the field and seige gun work, September 1, 1892 Lieut. William Peirce assists in the supervision at the gun shops and is adjutant at the post. The above named officers have, in ad- dition, to perform the various military duties incident to a military post. Anthony Victorin, M.E., has been em- ployed in designing, oe and set- ting up the machinery and in the construc- tion and equipment of the main building. ee WORLD'S FAIR NOTES. Getting Ready for October, House cleaning has begun at Jackson Park in anticipation of the dedication ceremonies; a very large force of men is employed on this work. The building of roads and paths is progressing rapidly, and walks and flower beds are being laid out on the terraces along the grand basin. The completion of the Manufactures Building, in which particular interest is just now centered, is in sight, and there is no doubt of its being in readiness for the ceremonies. The steel work of the roof will be com- pleted within a week, and the carpenters and staffmakers are as close upon the iron workers as possible. The artists who are decorating tbe interior of the domes over the entrances are on the ground. Work on the main building of Machinery Hall is progressing rapidly. The placing of the ornamental staff work has also begun, and the foundations for the boilers and engines in the power house are being placed. One Worthington pump of the capacity of 12,500,000 gallons is in place in the pump house. The exterior of the Administration Build- ing is practically completed with the ex- ception of coloring and placing the groups of statuary. Artist Dodge is at work on the statues for the decoration of the outer dome. The figures in this work will be 30 feet high. The exterior ornamental iron work of the dome of the Horticultural Building is being painted. This building and the Woman’s Building were given a roof test last week by two fire engines. The deluge of water disclosed some leaks, which the roof contractors will repair at once. Actual work on the Transportation Building’s annex will begin shortly. The roof of this annex constitutes a terminal for the ele- vated railroad. Building work has begun on two annexes for the Fine Arts Building. Contracts were let for the stock pavilion and excavations for the foundations were begun. Work will soon begin on the Pho- tographic Building. The big dome of the Illinois State Building begins to loom up. The big plate-glass tanks in the aquaria of the Fisheries Building are nearly com- leted and some of the fish will be placed in them next month. Work has begun on the clam-bake restaurant, where the old original New England clam bake will be exhibited and eaten. As weather will per- mit, work is being pushed on the big pier. Little has been done in the construction work during the recent rough weather, but a large portion of the old breakwater has been torn out. It is confidently expected that the music hall, casino and peristyle will be finished by October 15. Designer-in-Chief Atwood has completed the design for the magnificent ornamental centerpiece for the floor of the Manufact- ures Building to mark the juncture be- tween the space of exhibition assigned to France, England, Germany and the United States. This design will be submitted to the commissions of the three foreign coun- tries for their approval. This decorative feature was proposed some months ago by Sir Henry Wood, secretary of the British Royal Commission, and in furtherance of September 1, 1892 the idea Mr. Atwood has prepared the design. Navigating the Lagoons and Canals. Visitors to the World’s Fair will be af- forded the opportunity of a 3-mile ride through the canals and lagoons about the wooded island in Jackson Park on a fleet of electric launches. The idea of substituting electric motive power for steam in the propulsion of these pleasure craft was advanced nearly two years ago by the landscape gardeners of the exposition, F. L. Olmsted & Co. Like many other features of the exposition, this fleet of electric boats will be a new depart- ure. It is well known that throughout the entire world there are less than half a dozen electric launches. But the Exposi- tion Company were willing to follow the suggestion of Mr. Olmstead, and as a re- suit a contract has been awarded the Elec- tric Launch and Navigation Company of New York for the construction of 50 boats 34 feet long with 6 feet breadth of beam, and 20 additional launches of a smaller size. The first number is expected to make the 3-mile round-trip course from the grand basin at the south end of the park northward through the north canal and around the wooded island to the starting int in one hour. There will be 15 land- ings, so that passengers will be enabled to embark or disembark in the immediate vicinity of 13 of the great buildings. The scenery, or rather views, along the route will be the finest in the exposition grounds. In addition to the main fleet there will be 20 small launches to be engaged by pri- vate parties by the hour. ‘They will run in no particular direction, but be subject to the orders of those engaging them. The large launches will carry from 25 to 30 passengers each. The motive power is generated by a storage battery of 62 cells of the Consolidated Electric Storage Com- pany’s type. The power is communicated through a 4-horse power motor of special design, capable of developing 12 electrical horse-power for spurting. The propeller is 18 inches in diameter, with 12-inch pitch. The launch is fitted up with elec- tric incandescent lights. The officers of the Electric Launch and Navigation Company are E. J. Moore of New York, acting president; Alfred Skitt of the same city, secretary and treasurer, and Gen. Charles H. Barney of New York, general manager. To provide for transportation along the exterior waters of the park a concession has been granted to Meeker & Willard of Chicago. This company will build 20 steam launches, each 50 feet long. They will be equipped with triple-expansicn compound engines, with keel condensers. Anthracite coal will be used, so that neither smoke nor steam will be emitted. The route for these boats will be from the south pond north to the south inlet, through it, and around the main pier, 2500 feet long, west again to the main basin, where a turn will be made, and then north along the lake shore to the north inlet as far west as the Fisheries Building, and then return south over the same course. The Device for Securing Harmony. The Council of Administration of the World’s Fair met and organized Thursday morning by the election of H. N. Higin- botham, president, and A. W. Sawyer, assistant secretary. Mr. Higinbotham is president of the Chicago Board of Directors. His addi- tional elevation to the presidency of the council has been conceded for the reason that, as president of the directory, he represented the body which furnishes the money for conducting-the fair. The coun- cil is composed of four members, Messrs. THE IRON AGE. 471 and J. W. St. Clair and George V. Mas- sey of the National Commission. After electing a president the council immediately elected Mr. Sawyer assistant secretary. Mr. Sawyer has been secretary of the Committee on Grounds and Build- ings since its formation over two years ago. He has handled the enormous busi- nes3 of the committee in a manner so satisfactory that not a single complaint has been made. His knowledge of expo- sition work will be extremely valuable to the council, since it has on it but one member, Mr. Schwab, who could be con- sidered familiar with the construction work at Jackson Park. The council which thus began its official existence was provided for by the National Commission and the local direc- tory with a view of creating a joint body whose decision should be final in the set- tlement of any questions of difference which might arise in the administration of the fair by Director-General Davis and Minister of Works D. H. Burnham. The council is given further authority of an extensive character in the general direc- tion of the exposition management. It is composed of what have been hitherto op- posing elements. The representation is equal. No provision is made for a casting vote, and in case the members of the coun cil should get into a squabble they would make their organization ridiculous, since they have been selected as an arbitration committee. Exposition officials generally believe that the council will prove a success. They say that good men have been selected and that they should get along without dispute. Most feel confident that such a result will be attained. All admit, however, that the new board is an experiment. One of the first things which Director- General Davis will bring to the attention of the council will be a request for ar additional building to relieve the Manu- factures Building of 400,000 square feet of space. He needs that much additional room in the big building. Twenty-two nations are asking for space in that depart- ment and cannot be accommodated. After all, it seems that although there are 40 acres of floor space in the Manufactures Building. there are but 12 acres available for exhibits. This, at least, is the way Colonel Davis figures it. Deductions are made, of course, for aisles, posts and openings in the gallery floor. Michigan's Novel Exhibit, The exhibit of material things at the World’s Fair by Michigan will be supple- mented by a varied assortment of photo- graphs covering all sorts of subjects. President I. M. Weston of the State Com- mission has outlined plans for the camera to carry into execution, and the photo- graphic display will be full of instruction and interest. It is proposed among other things to have the pictures of all State buildings, including the State University at Ann Arbor, the Normal School at Ypsilanti, the Agricultural College at Lansing and the Mining Schovol at Houghton. Photographs will also be taken of the colleges. The principal churches in the State with portraits of leading divines, public school houses, &c., will form an interesting group. Portraits of all the Governors, of the United States Senators and Congressmen, and other prominent men in civil and military life, will form an interesting picture gallery of Michigan men for the World’s Fair visitors to look at. The industries of the State will be illus- trated by photographs of mining, lumber- ing, farming, fishing and shipping scenes, of factories and various manufacturing plants. The summer resorts will be given Higinbotham and Schwab of the directory, |a place in the a'bum, and the prettiest parks and breathing places in the State will not be left out. The resources of the State will be depicted by photographs of the 70 different kinds of timber trees, in- terior and exterior views of mines, of fishermen making a haul, of stone and marble quirries and of orchards and farms. The picturesque will be covered with a variety of photographs of land and water views, and the historic will show views of the forts at Mackinac and the Soo, of the ancient churches in Detroit, St. Ignace, Harbor Springs and other places, of the old State Capitol and the early log cabins which are still to be found in the back districts. Another novel feature in the Michigan exhibit will be a bird’s-eye view of the State, 14 feet square, showing every river and stream, every county, city and village in the State, the hills and valleys, the nature of the soil, the character of the timber and the various mineral deposits. The map will be drawn from an imaginary point about 2 miles above the city of Toledo, and the view obtained will cover Lakes Michigan, Huron and Superior, the Upper Peninsula and a portion of Wiscon- sin. The map will c~st about $1000, and will require six months of hard work to prepare. Similar maps on a smaller scale will be prepared of Grand Rapids, Detroit, Saginaw, Muskegon and other cities, but these will be paid for by the cities inter- ested and not by the State. The Design for the Souvenir Coin, Decisive action has not yet been taken on the design for the souvenir coin. While the law in this matter states that the designs shall be approved by the Sec retary of the Treasury and the Director of the Mint, yet these officials deemed it proper to have the proposed coins satis- factory to the managers of the big fair. Any suggestions made by the latter will be duly considered at the Treasury De- partment, and care will be taken to have the designs conform as much as possible to the wishes of those directly interested. Within six weeks after an approved de- sign is submitted to the mint at Philadel- phia pieces can be struck for distribution by the Sub-Treasurer at Chicago. Prob- ably by May, 1893, at the latest, the entire issue of coins authorized by Congress can be in Chicago ready for use by the exposi- tien management. Director Leech will push the work of making the coins as rapidly as possible after the designs are returned from Chicago. Meanwhile noth- ing has been done in the way of making another engraving for the obverse to take the place of the Lotto portrait of Colum- bus, which seems to be the only objection- able feature for the proposed coin. No one has thus far interposed even a remon- strance against making the reverse of the coin illustrate the beauties of the Govern- ment building at Jackson Park, and any further delay must be blamed on the local directors. Views on Souvenir Coin Sales, Government officials are watching closely the experiment of selling souvenir half- doilar coins for a dollar. Several applica- tions have been received by the Director of the Mint, at Washington, from banks and other institutions, for the purchase of coins in lots from 1000 up to 5000, These have all been answered by the statement that the Treasury Department has no authority to sell any of the coins, as they must be delivered to the exposition. Most of those who have had experience with ex- positions doubt whether the directors will realize their hopes and secure $5,000,000 from the $2,500,000 appropriation. It is pointed out that 5,000,000 souvenirs is an Immense number, and will satisfy an ex- tensive demand at the ordinary value for commercial purposes. When it comes to : 0) “Wi We peas LEEDS BV RD aS ~ Saat ~ es = Sy BH} YS) Wee ie soba” ae ae as “a aes ee * y = Soa £ = = rss 372 doubling that value they don’t know how the public will take it. The officials of the Census Office say there are about 12,500,000 families in the United States. The average is a trifle less than five persons toafamily. It is notice- able that in the detailed analysis of race, nationality, conditions and so on, the larger families are those who will be the least likely to be able to visit the fair, or to possess themselves of any of its souve- nirs, So it is questioned whether one- third of the families of the United States will really want a souvenir half-dollar coin at the expense of a dollar. The foreign demand could be subtracted from the 5,000,000 half dollars, and there would be enough of them to provide one for every third family in this country. During the debate in the Senate Mr. Sherman gave it as his opinion that 100,- 000 souvenir coins would supply the en- tire demand, but there was no one who agreed with him, though many Congress- men thought that 1,000,000 would be ample. Senator Pettigrew, who is chairman of the Quadrocentennial Committee, takes a different view. Speaking of the matter a few days ago, he said: ‘‘I predict that the time will come when those souvenir half dollars will be worth $3. In the tirst place, the demand from foreign countries will be much greater than has been sup- posed. A man told me the other day that he intended to buy 150 of them to send to European friends. I gave that as an illus- tration. Then our people at home will want lots of them. I think that every- body who goes to that fair will want a souvenir half dollar, and when you figure out the attendance, you can get pretty near the probable demand.” Treasury officials do not take so sanguine a view. To Get More Space. Director-General Davis has received from his department chiefs an aggregate of the amount of space applied for by in- tending exhibitors. These applications foot up 6,664,000 square feet, or approxi- mately 152 acres of space. All the depart- ments have not been heard from. The Director-General has not as yet issued orders for the awards of space. The ap- plications will be carefully considered. Some of them are for twice the amount available in the buildings in which appli- cation is made, The applications in the several departments are as follows: Agri- culture, 618,000 square feet; viticulture, 382,000; mines, 608,000; machinery, 975, 000; transportation, 890,000; manufact- ures, 1,775,000; electricity, 366,000; fine arts, 281,000; liberal arts, 704,000; ethnology, 64,000. Forestry, live stock and fisheries are not reported. When these are in there will be a still greater demand for space than is available. Some relief is promised by the action of the Executive Committee on Friday. A resolution presented to it by the Commit- tees on Manufactures and Ethnology asked that a special building be erected for the ethnological exhibit. The resolution was referrea to the Council of Administration. The proposed structure would relieve the Manufactures Building of 160,000 square feet, which has been set apart for ethnol- ogy. Of this 160,000 square feet 120,000 would probably be distributed among foreign nations. Of these there are 22 which have been debarred from representa- tion in the Manufactures Building through lack of room. The remaining 40,000 square feet would be devoted to domestic manu- factures, Two and a Half Acres for Trunks, The Pennsylvania Railroad Company have made arrangements to provide them- selves with 2} acres of floor space for stor- ing baggage during the World’s Fair. THE IRON AGE. The company are extending their baggage depots at the Union Station, corner of Canal and Adams streets, 250 feet north and 250 feet south, the additions being three stories high. Besides this the com- pany have rented the Armour warehouse, near Canal and Van Buren streets, thus increasing the capacity for trunks by 30,000 square feet. The company, all told, will have the following baggage space: One three-story building 275 x 25 feet, one six-story building 100 x 50 feet, two three-story buildings 245 x 25 feet, and two two-story buildings 250 x 30 feet, making the total of about 24 acres of floor space, The volume of baggage during the ex- position will be exceedingly large, and it is expected that the demand for trunk room will be increased by the need of storage for people who make Chicago a headquarters for short excursions into various parts of the country and whose bulky luggage the hotels will be unable to care for during their absence from the city. r Miscellaneous. George S. Morrison, the eminent engi- neer, has withdrawn his proposition to erect a tall tower on the exposition grounds, This ends the long series of ne- gotiations for a lofty structure which it was intended should overtop in hight the Eiffel tower at the Paris Exposition. The towers on the World’s Fair grounds will average about 400 feet high. There will be two, not more than three of them, each of which will be of artistic design, and in /harmony with the surrounding buildings. The Austrian wood-carving industry will be specially represented at the Chi- cago Exhibition by thirty-four expert wood carvers from Vienna, who will ex- hibit their work in its various branches. Everything is being done to organize a thoroughly representative and interesting collection of exhibits. Among recent applications for space in the railway division of the Transportation department is one from the Yale & Towne Mfg. Company of Stamford, Conn., for a 7-ton locomotive crane to be mounted on a platform standard gauge car 144 feet long by 11 feet wide. It will occupy in operation a circular area of 46 feet in diameter. In the main s:ction of transportation exhibits Stewart & Binney of Boston will use about 400 square feet of wall and floor space for the display of models, photo- graphs and pa‘ntings of yachts, fishing vessels and other vessels by that distin- guished architect, the late Edward Bur- gess. a As bearing upon the relative value of steel and iron pipe, and the facility with which it can be worked by the consumer, we are informed by the Riverside Iron Works of Wheeling, W. Va., that they have entered orders during the current vear for nearly 1,500,000 feet of 1-inch steel pipe from B. F, Sturtevant & Co. of Boston, who cut and thread more pipe than any single concern in the country outside of the pipe mills themselves. The River- side Iron Works state that they do not find it necessary to make special concessions in competition with iron pipe. There has been issued in pamphlet form a lecture delivered before the Franklin Institute by John M. Hartman, the well- known furnace engineer, of Paoiladelphia, entitled, ‘‘ Notes on the Blast Furnace,” Ports on Puget Sound are growing in importance. A fleet of 91 loaded vessels sailed from Puget Sound and British Columbia ports last month with cargoes worth nearly $900,000. September 1, 1892 HIGH-PRESSURE HYDRAULIC PRESSES IN IRON WORKS.* BY R. M. DAELEN, DUESSELDORF, GERMANY, (Concluded from page 330, August 25.) Special Forms. The field of application for the systems of producing water pressure increases with experience and with the improvements devised to overcome the difficulties en- countered in practice. Consequently, local conditions are becoming more and more decisive in the choice of a suitable sys- tem. The Pneumatic Accumulator. — The reasons for avoiding the use of the ac- cumulator are partly removed by the pat- ent pneumatic hydraulic accumulator of Prétt and Sulhoff,* which successfully substitutes air pressure for a constant weight, so that, in rapid changes of the water speed, the effect of the momentum of a weight, increasing seriously the result- ant shocks, is eliminated. Fig. 8 shows one form of this accumu- lator. It consists essentially of an air cyl- inder, A, with plunger, a, and a water cylinder, B, with plunger, ), having, for instance, one-tenth the area ofa. Hence, if the pressure in A be 50 atm., and water is forced through e into B so as to raise « and /, the pressure in B will be 500 atm. When water is forced into B, the air in A will be compressed; when water is taken out of B, the air in A will expand and drive the plunger down--but without shock, even if the speed be high, F F are auxiliary air receivers, of which there may be any desired number (the large ac- cumulator at Bochum has six), and which may be cut off or connected by valves, as at 7, as required to increase the air space, and diminish proportionally the range of pressure in A, and the consequent inten- sity of the pneumatic reaction. The cast- steel plunger a is made hollow to give ad- ditional air space. The amount of air is constant, except for loss by leakage. To prevent this, a liquid (preferably oil) is in- troduced above a (as shown in the figure opposite the oil gauge g), and is allowed to penetrate also into the small annular space between the walls of the plunger a and a water-tight lining, A, of wrought- iron plate. The manufacturers say that without this protection the best steel cast- ing would not be tight under an air press- ure of more than 50 atm. Oil isintroduced through g by means of the valves shown at the right of /, which leads to the air pump. The pump is engaged or disengaged by mears of mand n. For further details, the description in Stahl und Lisen, cited above, may be consulted. The manufact- urers, Breuer, Schumacher & Co, of Kalk, uear Cologne, have printed an English translation, which they will doubtless furnish on application. Applications of the Steam Intensifier — In most recent times, improvements in the control of the hydraulic column (to be de- scribed below) have essentially facilitated the use of a central high-pressure genera- tion, with or without fly wheel, so that this system can now be employed for the largest forging presses connected with iron and steel works, whereas it was formerly more or less confined to establishments. having many departments, such as bridge shops, shipyards and boiler manufac- tories, in which the tools for adjusting, cutting, punchir g, bending and riveting wrought iron were operated by hydraulic pressure. The pressure, which formerly seldom exceeded 100 kg. per square centi- meter is now carried considerably higher. * Read at the Baltimore meeting of the American Institute of Mining Engineers. * See Stahlund Hisen, 1891, No. 2, p. 182. September 1, 1892 THE IRON AGE. 373 { For the presses used in plate mills to bend, corrugate, cut and stamp the plates, the simple intensifier, shown in Fig. 3, has largely taken the place of the pump with accumulator, having already proved its excellence in other directions, as, for | instance, in the operation of billet shears. Fig. 1, already referred to as illustrating the general principle of the intensifier, represents also its application in the patent vertical bydraulic shearing machine, with direct steam driver, of Breuer, Schumacher & Co. This machine, designed for shear- ing hot steel ingots, consists essentially of the steam intensifier already described, from which the working cylinder D de- rives (through water or other liquid) the | pressure, which is communicated through E to the blade F. A small steam cylinder, G, above the shear frame, lifts E, with the upper shear F, after the cut, to their ini- tial position. On the cylinder A the steam valve /, operated by the hand lever «, di- rects the steam alternately into G and A. When, by depressing the lever a, steam is admitted to the large cylinder A, the piston rises, and E, with the connected cross head m, are forced down by the pressure of the water forced by B operat- ing in C. In this down stroke m, gliding upon the curved lever /, moves (in corre- spondence with the curve of J) the steam slide of }, so that after the cut has begun the steam is first throttled and afterward cut off from A entirely, leaving the re- mainder of the cut to be effected by ex- pansion only. In other words, when the resistance of the bloom is highest the steam inlet of A is entirely open, and as resist- ance diminishes it is proportionally closed. Finally, when the cut is finished, m and 7 automatically reverse and open the outlet for the steam in A, the piston of which then returns by its own weight, being suit- ably cushioned by the controi, through /, of the steam escape. Many devices have been patented for ap- plying to different purposes the principle of direct transformation, by means of the intensifier, of steam into water pressure. Amo