CHAP. IV., 5.] 



MECHANICS. TKEVITHICK G. STEPHENSON. 



83 



Mr Clements were broken off, the difficulties of the 

 affair became insurmountable, and the construction 

 of either engine has for some years been in abeyance. 

 The opinions of men of science are not unanimous 

 as to the great practical importance of calculating 

 tables by machinery, but the improvements of me- 

 chanical contrivance which the joint skill of Mr 

 Babbage and Mr Clements introduced into engi- 

 neering workshops are unquestionably of great impor- 

 tance to the arts. Though the details of Mr Bab- 

 bage's plans have not been published, there can be 

 no doubt that, whether economical or not as sub- 

 stitutions of machinery for human labour, they were 

 devised with remarkable skill and ingenuity, and even 

 on this account merit preservation. 1 



(380.) Recently (1855) attention has been directed in 



M.Scheutz L on d on to a simple and effective Difference Engine 



engine. constructed and patented by M. Scheutz, confessedly 



on the principles of Mr Babbage, though without an 



acquaintance with his mechanical contrivances. The 



result is stated to be satisfactory. The engine deals 



with fifteen digits or figures, and with four orders of 



differences. Only eight figures are preserved in the 



result, the others being reserved to prevent errors 



arising from the accumulation of still lower digits 

 omitted. The engine not only computes with facility 

 and accuracy, but, by means of steel punches impress- 

 ing lead, provides for the perpetuation of the num- 

 bers in the form of stereotyped plates. The work- 

 manship of the whole requires no particular nicety 

 of execution, is not liable to derangement, and can by 

 scarcely any contingency produce inaccurate results. 



Before closing this section, we may advert to im- (381.) 

 provements in the theory of machines by those who Foreign 

 have regarded it rather from the geometrical side ^g^ n 

 than from that of routine practice. Our French O f ma- 

 neighbours have been distinguished in this respect, chines. 

 Carnot and De Prony, MM. Hachette, Poncelet, and 

 Morin, have been or are accomplished mechanists in 

 this respect ; and in the French repertories we must 

 look for some of the earliest good scientific descrip- 

 tions of machinery, even when of English invention. 



In England, besides Mr Babbage, Professor Willis (382.) 

 of Cambridge has shown a peculiar aptitude in this En S llsh 

 department, and has published a very valuable work au 

 on machinery, regarded in a strictly geometrical sense. 2 

 To Mr Moseley we are likewise indebted for some va- 

 luable contributions to the theory of engineering. 



5. TREVITHICK. GEORGE STEPHENSON. The Locomotive Steam-Engine. Rise and Progress 



of Railways. M. de Pambour on Locomotives. 



(383.) 

 The loco- 

 motive en- 

 gine and 

 railway. 



(384.) 

 Early anti 

 npation 

 )f steam - 

 carriages. 



Of all the inventions which have powerfully af- 

 fected the interests of mankind, none have been more 

 slowly perfected, or can be less certainly traced to a 

 single individual as the inventor, than those of the 

 Locomotive engine and the Railway. These two great 

 and essentially connected portions of the greatest 

 mechanical and commercial effort of any age or 

 country had their origin in obscurity. Each ap- 

 peared several times to be rising into the import- 

 ance it deserved, but failing the concurrence of 

 the fortunate circumstances which are necessary to 

 give permanence to invention, was once more for- 

 gotten and was left for re-discovery at a happier 

 epoch. 



With regard to Steam-Carriages, passing over still 

 earlier speculations, we find that Dr John Robison, 

 at the age of twenty-one, published a design for a 

 steam-carriage in the Universal Magazine for No- 

 vember 1757, and that he also directed Mr Watt's 

 attention to the steam-engine in the same year, with 

 a view to this very application. The cylinder of the 

 proposed machine was an inverted one, and Watt ac- 

 tually made a rude model on Robison's suggestion. 8 

 From this time the steam-carriage seems never to have 



been long lost sight of by mechanical speculators. 

 It was included in a patent by one Moore, a linen 

 draper, in 176 9. 4 In the same year it is stated that 

 Cugnot, a native of Lorraine, actually constructed 

 a steam-carriage, which, like the nearly contemporary 

 but unsuccessful efforts of his countrymen to effect 

 steam navigation, fell speedily into oblivion. About 

 1773 Edgeworth of Edgeworthstown urged the con- 

 struction of steam-carriages, and at a later period ex- 

 pressed, in terms of unequivocal anticipation, the 

 triumph arising from their connection with railways. 

 " I have always thought," he wrote in 1813, "that 

 steam would become the universal lord, and that we 

 should in time scorn post-horses. An iron railroad 

 would be a cheaper thing than a road on the com- 

 mon construction." At Soho the movement of car- 

 riages as well as of boats by steam never was or could 

 be forgotten. In Watt's patent of 1784 the steam- Watt and 

 carriage forms the seventh article, and in the same 

 year 5 Mr William Murdoch, a member of Boulton 

 and Watt's establishment, made a model, acting by 

 high-pressure steam, which drove a small waggon 

 round the room. Hence it required no prophetic 

 power in Darwin, the intimate friend of Watt, to 



1 For historical details connected with Mr Babbage's engine, see Weld's History of the Royal Society, vol. ii. An account of 

 the principles and action of the Difference Engine may be found in the Edinburgh Review for July 1834 ; and those of the Ana- 

 lytical Engine in Taylor's Scientific Memoirs, vol. iii. 



2 Principles of Mechanism. Camb., 1841. 3 Mechanical Inventions of James Watt, ii. 294. 



4 Mechanical Inventions of James Watt, i. 52. 6 Translation of Arago's Eloge of Watt, p. 120, note. 



