28 



THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



[January, 



ON THE l'0\\i:U OF THE STEAM ENGINE. 



At tlic last mcoling of I lie ('ornw.ill I'olylecliuic "Sooiety, Iiclcl .if Falinoutli, 

 Mr. Snow Harris yc:u\ an abstract of an inlorcstini!; and valnalilc ])aiier on the 

 Sleani-nigiiio, )iy Professor Moseley, lie^asset! a liigli eulogintn on lliat gcn- 

 tli-Mian \vliose pajter, lie said, possessed a great deal of infciest to the wm'kiiig 

 engineer and praelieal miner. The details of the paper wonhl, however, he 

 too tedious to hringhefore aniixed audience, and he had tliercforc alistracted 

 the principal |ioints which it was necessary to hring under their considertion. 

 I'rofessor Moscley ajijjcared to think that the eflieieiicy of a steam engine 

 could Ite nicasiu'ed only hy ohseiTations of the cylinder itself, hecanse tlie 

 estiroafe at any other ]daee was less than tin; ai'tnal deficiency on account of 

 friction and other canscs. Hence they conh! not U'U t'l /iriori of what the 

 engine was capable. If tlicy had a good mcasurenieni of the ctliciency at the 

 cylinder, and also of the work actually ])erfornied, they should then arrive at 

 a true estimate of the power of the engine, and also of the loss hy friction, 

 i\c., by subtracting one from the other, in the Cornish engines they had 

 already the eflieieney of the working parts ; they rcquireil, therefore, the only 

 observations at the cylinder. It was the dirt'erenee of these which was the 

 efficiency for the pit work, and of so touch importance to the adventurer and 

 engineer. Professor Moseley jiroposcd to arrive at the efficiency of the 

 cylinder by connecting a seeoml smaller eylin<Ier with it. of aluint six inclies 

 diameter, so as to allow of the steam acting u])on a sju'ing through the me- 

 dium of a solid ])lng in the latter. Tlie writer thought the cft'cctive pressure 

 upon this plug as indicated hy the (piantitatum measurement by means of the 

 steel spring will be always equal to thai njion an equal area of the piston of 

 the engine; so that knowing one of these pressures they coidd always deter- 

 mine the other — namely, tlie eircctivc ))ressiire. The author proceeded to 

 explain by diagrams a practical method of carrying out bis general principle. 

 lie further thought that they not only wanted to know the eft'ectivc ])ressure 

 throughout the whole duration of the stroke, but .also how much of the stroke 

 was described under any given pressure. The author furnished methods for 

 arriving at this important clement which were well worthy of attention, and 

 were such as to apply either to a long period as a month, or a short ]ieriod 

 of six hours. The Professor considered that the o>it as well as the in stroke 

 should he registered, and he gave an arrangement for the purpose, and the 

 results were registered iijion indicator diagrams, diflerent from those of M'att, 

 and upon an area sixty times as great. There seemed but little doubt that 

 the author of this paper, which must be considered as an extremely imjiortant 

 one to the practical miner and engineer, bad succeeded in inventing methods 

 for arriving at the efficient power of the steam engine. It was the mechani- 

 cal details which rcquireil consideration. They must obtain very perfect 

 sjirings calculated to yield through spaces proportioned to the jircssures. This 

 was a vital affair, for should not such be the case the indications would be 

 erroneous. The author thought th.at this property could be given to s]iiral 

 sjirings, as well as to bow springs of a given form ; and that w ith due correc- 

 tion for the friction of the small cylinder, the method might be m.ide practi- 

 cally perfect. Mr. Jordan, with his iisu.al ability, had given a drawing of the 

 indicator, and had contributed largely to its meeh.anical .advancement. Pro- 

 fessfu* Moseley projiosed to call this instnnoent the pif vork counter, because 

 it indicates, by eomi>arison with the counter in present use, the amount of 

 the pit work. Mr. Harris concluded by observing that this was a brief ab- 

 stract of the \ery valuable jiajier furnished by Professor Moseley, and he was 

 only sorry that the time allowed him had not jiermitteil him to do Professor 

 Jloscley more justice than he had on the present occasion. 



Steam Apparati's.— There is in the Oxford Union workhouse a steam 

 apparatus by means of which the whole of the clothing and other articles 

 used in it are washed, dried, and ironeil, in an incredibly short space of time. 

 M'e have lately been atforded an ojijiortnnity of witnessing this useful jiieee 

 of meebanism in o]>cratioii, on whicli occasion no less than 123.') articles of 

 wearing .apjiarel, bed-clothing, &;c., were washed, dried, and ironed, in two 

 da>*s. wilh the assistance of only eight v\<)men and two girls from the school. 

 It is the invention of James \Va]ishare, V,f'\., of liatb, for which we under- 

 stand he has obtained a jiatent, and was some time since erected in one of 

 the wings of the Imilding solely devoted to the ])urposes of a laundry, at the 

 cxjicnse of the chairman of the Board, the Kev. N. Hudson. The ajiparatns 

 consists of a small steam boiler, with two pijies for the conveyance of steam. 

 J!y the one pipe the steam is conducted to the coppers used for boding the 

 clothes and supplying the washers with hot water, by the other the steam is 

 carried to a closet in which the linen is to be dried. The exterior of this 

 cJoset is a wooden frame covered with /.inc, within it is fitted uji with pipes, 

 increasing in number ai'cording to the extent of drying ]iower required. 

 These ]ii]ies are arranged horizontally one above another, resembling a turn- 

 pike gate; excepting that the mils are connected at one end only by a bend 

 or turn, thus finniing a continued duct for the steam. The steam is admitted 

 at the upiicrpipe, and p.asses its conilensed water at the lowest. t)ii either 

 side of tliis tier of pipes is a movable clothes horse, xvbich is drawn out to be 

 hung with clothes. Ujioii the construction of these horses the ojieration of 

 drying in a great measure depends. They are made close at the toj) of the 

 box, so that no heat may escape over tlieiii, and the clothes arc so disposed 

 on them as to form an entire sheet, completely enclosing the pijics, and ]ire- 

 venting any escape of the heat radiating from the jiipcs, except by passing 

 through the clothes to be dried. Tliis disiiositiuii of the clothes is easily 



accomphshed. but difficult of description. On the outside of the horses, or 

 on that side which is not next the jiipes, a valve or oiieiiing is made on the 

 top of the box', and a cmTCut of air being admitted at the bottom, the steam 

 from the clothes is carrieil off as fast as it is generated. One set of these 

 pipes, with two horses, would be sufficient for any moderate family. In an 

 establishment so extensive as an Union house more is required, in the closet 

 erected arc three ranges of pipes, and consequently six horses or two to each 

 range, having an air space, with its valve between each set of horses. At- 

 tached to the flue that suiTounds the boiler is a sm.ill oven for heating the 

 irons, so that the whole operation of the laundry, as far as heat is required, 

 is simultaneously effected by one fire. — Oxford llci'altl. [We insert this 

 notice, not for its novelty, but for its ulility, and to show the a])])Ii<>ation of 

 steam to domestic purjioscs, in the erection of extensive buildings intended 

 to contain a large number of inniales. We cannot, from the above descrip- 

 tion, ascertain what claim Mr. M'ajishare can have for a iiatent, as similar 

 arrangements have been adopted many years past. — Eo. C. E. iV \. Jour.] 



Hakkoor Crank. — A crane eajtable of raising great weights at the har- 

 bour having been found indisiiensahle, a considerable time since, Mr. Leslie, 

 engineer to the harbour, executed a jilan for a machine cajiable of raising 

 thirty tons. The merit of the design hasbeen very extensively acknowledged 

 among professional men, and those who are initiated in mechanics. Mr. 

 Peter Borric, the contractor for the work, has been eng.iged for sometime 

 past in easting the diflerent ]'arls of the crane. The novelty of the design, 

 and the magnitude of the work, evince the skill antl attention which must 

 have been bestfiwed upmi its comjilction. The gross \\eight of the post, in- 

 cluding the back and side tension-bars, friction collar, hoops, &'C., is no less 

 than twenty-five tons, or within ten tons of the weight which it is intentled 

 to lift. The pedestal for this crane is a beautiful piece of nmsoiuT ; and 

 rising considerably above the quay, /it was ne<'essary to raise the post to an 

 elevation of fifty-five feet before it could be put into its jilaee. This was 

 done by two tackles and crab windlasses of great power — the upper blocks 

 being fastened, at a height of sixty feet, to the apex of three shear poles. 

 The whole time oceupieil in the transit of tl«' axle pole, and in raising and 

 lowering it into the east-iron cylinders, did not exceed six consecutive hours. 

 Ten men were found adequate to perform the whole ojicration of raising and 

 lowering the ]iost, and adjusting it to its jnoper position in the cast-iron 

 cylinder. The extreme length of the jiost over all is nearly forty-five feet. 

 .\s the crane is not yet completed, we cannot speak of it as a whole ; hut 

 there cannot be a doulit that it will be a great advantage to the large class 

 of steamers, especially to our yet unrivalled I.omlon steamers. And we 

 understand that as soon as it is ready, and disengaged (for the steamer Perth 

 has secured the first turn), a very large steamer from a distance is to be 

 brought to Dundee in order to get in new boilers. In this way, we have no 

 doubt, an ample recompense xvill be olitained for the great aeeommodation 

 now to be given for the shipping at the port. Much woik, auda consider- 

 able amount of shore-dues, may, in eonsequence of the facilities afforded by 

 the crane, be brought to Dundee, which otherwise would have been lost to 

 it. The testing of this vast machine will be a process of some interest ; and 

 we have no doubt the successful result will add to the well earned rcjiutation 

 of Mr. Ueslie; and be highly creditable to Mr. liorrie, by whom the work 

 has been executed. — Dutulcr Courier. 



Skgui.n's Ammai. Gas .Vpparaths. — In a memoir on the compression of 

 gases, and on the reduction of vari.ible pressures into regular pressure, M. 

 Segiiin gives the Academy of Sciences a description of a new |)um)), with a 

 regulating apparatus, for the compression of gas for illumination obtained 

 from the distUlation of animal substances. The pump is so .arranged as to 

 give the maximum force at the moment of the course when the gas presents 

 the maximum of resistance by the dimimitiou of its volume ; to work in a 

 vertical jiosition without loss of gas, and without the jiiston being immersed 

 in fluid ; and lastly to avoid, by means of a particular mode of transmitting 

 power, the use of guides, which would cause a friction in the piston-rod, 



Articsiax Vkli.s. — M, ^'iollct b.as eommnnicated to the Academy of 

 Sciences the residts of the experiments which be has made at Tours, to aseer- 

 tiiin the quantity of water supplied by an .Vrtesian well, after some repairs 

 imdcrtakcu for the purpose of remedying a considerable diminution which 

 took place in the jiroduee. The repairs executed under the direction of M. 

 Mullot had complete success, and the well now serves to supply motive 

 power for the silk mill of M. Champoiseau. The well, which in July, 1834, 

 immediately after its comiiletion. only supplied lOOfl litres jier minute to the 

 surface, has since given the following results ascertained by gauging kept up 

 from the loth to the 23rd of May last. 



0-JO metres above the surface 34S0 litres per iiiitiute. 



i-7^ . . . 1620 



5-7.'> . . . IMO 



The well having been put into .action, anil supplying its water from the 

 23ril of .May from a new orifice, situated 5 metres above the surface, I found 

 by gauging, on the 2iid of August, a jiroducc of 1702 litres per minute, in- 

 stead of the IG20 only, which the orifice at A'7l> metres gave in the 23rd of 

 May. The iiroiliice li.as, since then, still further increased, which progressive 

 increase is attributed by M. VioUet to the alimentary channels being cleared 

 by the rejection of the s.and brought to the surface by the water of the v\ell ; 

 but it is imirartaiil, ,as it leads to the hope that the unfortunate diminution of 

 siipiily will not again occur. [\Vc cannot entertain the confidence of M. 

 Viollet, but must feel, to some extent, distrustful of wells sunk in sandy 

 strata, which arc exposed to many incynvcnicnccs,— Eb. C. E. & A, Jour.] 



