404 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



[October 



his two predecessors,* although he introduced some essentiiil modifications ; 

 that, among: others, of generating the steam in a separate vesseh t If it 

 is of little difference as to principle, whether the motive sieam be en- 

 gendered at the expense of the water to be raised, and in the very heart 

 of the boiler in which it is to act, or whether it originates in a separate 

 vessel, to act at pleasure, by means of a communicating tube, having 

 a cock above the liquid, which is to be raised, it is certainly not the same 

 in a practical point of view. Another change still more important, well 



his reader to suppose an eflFect produced of a different and important character 

 Herein we cannot but think tliat M. Arago*3 candour appears for a moment to have 

 yielded to liis desire to Halter the vanity of his countrymen, ami render himself popular 

 " In the second era, the era of successful application of the power of steam to useful 

 purposes, we find, first of all, the Marquis of Worcester. There is no doubt whatever 

 urged by M. Arago, against the auihcnticity of the Marquis's written and published 

 descriptions of the steam-engine, but he contents himself with asserting that the 

 Marquis never made his machine ! nor applied it to use, and that therefore he stands 

 on no bftter ground than De Caus. It is to be regretted, that M. Arago did not make 

 himself better acquainted with the published history of the ateam-engine, for he would 

 then have known that the Marquis of Worcester not only made a steam-engine, but 

 that it was applied to the purpose of raising water for the use of the inhabitants of 

 Vauxhall ; that it was of more than two-horse power, and that it was seen in operation, 

 amongst others, by Cosmo dt' Medici, on the 28th day of May, 1653, who gives 

 testimony thus — '* it raises water more than forty geometrical feet, by the power of 

 one man only; and in a very short space of lime will draw up four vessels of water 

 through a tube or channel not more than a span in width, on wliich account it is con- 

 sidered to be of greater service to the public, than the other machine near Somerset 

 House ; "—the machine at Somerset House being one driven by two horses. 



"Ill brief, let M. Arago say what he may, Worcester, Savery. Newcomcn, and 

 Snieaton, are the great names of this era; and Dr. Papin, though he made many 

 clever attempts at tlie contrivance of machines, on the principles suggested by his pre- 

 decessor, the Marquis of Worcester, and his conten.poraries, Savery and Newcnmen, 

 ■was never known to make a single successful attempt with steam, excepting applying 

 it to the extr.iction of nutriment from bones, an invention which bears his name, ami 

 for which alone it is that futurity v?ill ever mention it." — Note of ike translator. 



* Bonuani says, however, that aftt-r the death of Kirrher, there was found in his 

 museum the mod^l of a machine which ih.tt enthusiastic author had described in 1650, 

 and which (littered from that of Solomon de Cans, by the mere fact, that the motive 

 steam was engendered in a vessel totally distinct from that which contained the water 

 to be raised. — Note of M. Arago. 



It is thus that M. Arago gradually distributes in his notes the slain corses of Solomon 

 de Cans' competitors; but we leave to our readers to make their comments ou this 

 extraordinary line of conduct. — Note of the trartslator. 



t SAVERY'S ENGINE. 



It consisted of a furnace and boiler B ■, from tJie latter two pipes, provided 

 with cocks C, proceeded to two steam vessels S, whicli had branch pipes from 

 a descending main D, and also to a rising main pipe A; each pair of branch 

 pipes had valves a, h, to prevent the descent of the water raised by the con- 

 densation or by the force of steam. Only one vessel S, is shown^ the other 

 being immediately behind it. One of the steam vessels being tilled with 

 steam, condensation was produced by projecting cold water, from a small cis- 

 tern E, against the vessel; and into the partial vacinim made by that means, 

 the water, by the pressure of the atmosphere, was forced up the descending 

 main D, from a depth of about twenty feet ; and, on the steam being let into 

 the vessels again, the valve 6 closed, and prevented the descent of the water, 

 while the steam having acquired force in the boiler, its pressure caused the 

 ■water to raise the valve «, and ascend to a height proportional to the excess 

 of the elastic force of the st( am above the i)ressure of the air. 



Captain Savery afterwards simplified this engine considerably, by using 

 only one steam vessel. To prevent the risk of bursting the boiler, he applied 

 the steelyard safety valve V, invented by Papin for his digester. The cocks 

 were managed by hand ; and, to supply the boiler with water, he had a small 

 boiler adjoining "to heat water for the use of the large one, and thus prevent 

 the loss of time which must have occurred on refilling it with cold water. — 

 ^Tredyoid. 



worthy of special attention, and equally originating with Savery, will be 

 alluded to in the space we shall devote to the htbouis of Papin and 

 Newcomen. 



Savery had entitled his work. The Mhter's Friend, but the miners 

 showed themselves little obliped to him for his complidsance, for, with 

 only one exception, none of them give any orders for his engines. They 

 were only employi d in conveying water to different parts of palaces, 

 country-houses, parks, and gardens ; and were never used but in altering 

 the level from 1'2 to 16 yards. We must acknowledge, moreover, that 

 the danger of explosion would have been considerable, if there had been 

 applied to the ^paratus that immense power which their inventor as- 

 serted they could attain. 



Although the practical success of Savery was rather imperfect, yet the 

 name of this engineer merits a very distinguished place in the history of 

 the steam-engine. Persons whose whole life has been devoted to specu- 

 lative subjects, are unaware what a difficulty there is in bringing the most 

 apparently well digested plan into execution. I do not, like a cele- 

 brated German savant, pretend that nature ahi-ntjs cries out no.' no.' 

 when we wish to raise a comer of the veil which covers her, but by 

 following the same metaphor, we are at least allowed to affirm that the 

 attempt becomes so much the more delicate and difficult, and the success 

 80 much the more doubtful, as it requires the combination of a greater 

 degree of mechanical skill, and the employment of a large number of 

 material elements ; under every one of which considerations, and taking 

 the period into calculation, no one was ever placed in a more unfavourable 

 position than Savery. 



1 have spoken until now only of those steam-engines, the resemblance 

 of which, to those now bearing that name, is, more or less, indisputable. 

 Now I shall consider the modern utecim-engine, that which is employed in 

 our manufactories, upon vessels, and in tlie shafts of nearly all our mines. 

 We shall see it arise, increase, and develope itself sometimes on the in- 

 spiration of some chosen individual, some on the spur of necessity, for 

 necessity is the mother of genius. 



The first name which we find in this new epoch, is Denis Papin. It 

 is to Papin that France owes the honourable rank which she claims in 

 the history of the steam-engine. However, the really legitimate pride 

 with wliich we are inspired by his success, will not be withoiit alloy. 

 The claims of our fellow countiyman are only to be found in foreign col- 

 lections, his principal works were published beyond the Rhine; his 

 liberty was threatened bv the edict of Nantes, and it was m mournful 

 exile that he enjoyed for'a moment that ot which men of research are 

 the most desirous— tranquillity of mind. Let us quickly throw a veil 

 over these unfortunate results of our civil discords ; let us forget that 

 fanatici.sin attacked the religious opinions of the philosopher of Blois, 

 and get back to our machinery, with regard to which, however, the ortho- 

 doxy of Papin has never been contested. 



In every machine there are two things to be considered— on the one 

 hand, the movement, and on the other, the disposition, more or less 

 comp'lex, with fixed or moveable parts, by means of which the motive 

 power communicates its action to resistance. In the height to winch 

 mechanical knowledge has now-a-day been carried, the success of a 

 machine, intended to produce great effects, depends principally upon the 

 nature of the motive power, and on the means of applying and con- 

 ducting its power. And it was to the production of an economical 

 moor capable of communicating incessant oscillations, and with gieat 

 power to the piston of a large cylinder that Papin devoted his lite. To 

 borrow afterwards, from the oscillation, of the piston, a sufficient power 

 to turn the stones of a corn-mill, or the cylinders of a Hatting engine, 

 the paddle wheels of a steam-boat, or the bobbins of a cotton spinning 

 machine-to lift the clumsy hammer, which beats with frequent strokes 

 tbe colossal lumps of glowing iron, fresh from the reverberating fi.niace, 

 to cut like a riband in a lady's hand, thick bars of metal with tbe 

 sheering blade of gigantic scissars ; these are, I assert, so many pro- 

 blems of a very secondary rank, and which would not troidde the most 

 common-place mechanic. We can therefore employ ourselves in consi- 

 dering exclusively the means by which Papin proposed to engender his 

 oscillatory motion. 



Let us suppose a large vertical cylinder, open at lop, and resting at 

 the base, on a metal table, having a hole in it, closed or opened at plea- 

 sure by a cock. Into this cylinder let us introduce a piston, that is to 

 say, a circular plate full and moveable, which will close it entirely ; the 

 portion of tbe atmosphere which occupies the lower part of the cylinder 

 will then tend by its re-action to produce an inverse motion. This 

 second force will be equal to tbe first, if the cock be open, since a gas 

 press-s equally on all sides. The piston will then be acted upon by two 

 opposite forces, which will keep it in equilibrium ; although it will des- 

 cend, but only by its own gravity. A counterpoise in a small degree 

 heavier than the piston, will on the contrary be sufficient to litt it to the 

 topofthecvlinder, and to keep it there. Let us suppose the piston 

 arrived at this extreme position, and let lis endeavour to point out the 

 means of causing it to descend loith qreat force and to bring it back 

 again Iman-ine, that after having closed the lower cock, we succeed in 

 suddenhi auiiTbilating all the air contained in the cylinder, in a word to 

 empty "it. This vacuum having once been made, the piston only re- 

 ceiving its aclion from the external atmosphere which presses from 

 above, will raiwll,/ descend. This movement effected, the cock is opened, 

 the air immediately returns from below, and coimterbalances the action 



