ON THE PHYSICAL VIEW OF NATURE. 



133 



the theory of dissipation of energy." 1 Whilst Clausius in 

 Germany and Thomson in England were busy reconciling 

 the truths contained in Carnot's older researches with the 

 new conceptions firmly established by Joule's classical 

 measurements, putting both into mathematical and into 

 popular language, correcting our mathematical formulee as 

 well as our vocabulary, other applications of the new 

 ideas assisted in procuring for them general recognition 

 and acceptance. Eankine 2 in England, Zeuner 3 in Ger- mrn. er>an 



1 Lord Kelvin, in a paper read 

 before the Royal Society of Edin- 

 burgh, 2nd February 1874, on " The 

 Kinetic Theory of the Dissipation 

 of Energy " (' Proceedings,' vol. viii. 

 p. 325 sqq. ) See also his article in 

 the ' Fortnightly Review' for March 

 1892, reprinted in ' Popular Lec- 

 tures and Addresses,' vol. ii. p. 

 449 sqq. 



2 The earliest formal treatise on 

 thermo - dynamics was Macquorn 

 Rankine's article on " The Mechani- 

 cal Action of Heat" in Nichol's 

 'Cyclopaedia' for the year 1855. 

 The part he took in the develop- 

 ment of the new science was prac- 

 tical and at the same time highly 

 speculative. His papers on tem- 

 perature and elasticity of steam 

 and other vapours, on the expan- 

 sion of liquids by heat, and on 

 the mechanical action of heat, of 

 dates 1849 and 1850 (see ' Miscellan- 

 eous Scientific Papers,' ed. Millar, 

 1881, pp. 1, 16, 234), entitle him 

 to be considered as one of the 

 first if not the first (see his claim 

 to priority in a letter in Poggen- 

 dorfs 'Annalen,' p. 81, 1850) to 

 reconcile Carnot's discovery with 

 the mechanical view. His investi- 

 gations were peculiar, combining 

 practical applications of great value 

 and important predictions (see 

 Tait's memoir prefaced to Ran- 

 kine's ' Papers,' p. xxix) with daring 



speculation : his deductions being 

 founded on his theory of molecular 

 vortices. Though he exerted in 

 this country a great influence on 

 the early workers in thermo-dyn- 

 amics, his theories were scarcely 

 relished in Germany (see Helm- 

 holtz's criticism of Rankine's 

 methods in 1853, quoted by Helm, 

 ' Energetik,' p. 114), where Claus- 

 ius's independent and simultaneous 

 researches on the same subject had 

 meanwhile usurped attention. But 

 Rankine's ' Manual of Applied 

 Mechanics' (1857), his 'Manual of 

 the Steam-engine and other Prime 

 Motors' (1859), were the first books 

 of practical application in which, 

 through a happy nomenclature 

 and an extensive use of graphical 

 methods (Watt's indicator diagram 

 and Carnot's cycle), the new ideas 

 were introduced to a wider circle. 

 See Helm's estimate of Rankine's 

 work in 'Energetik,' p. 116 sqq. 



3 Somewhat later than Rankine 

 in this country, Zeuner in Switzer- 

 land and Germany, following upon 

 Clausius's theoretical memoirs, in- 

 troduced the mechanical treatment 

 of practical heat - problems. His 

 ' Grundziige der mechanischen 

 Warmetheorie ' (1860) was to many 

 a revelation. Appearing about the 

 time when the German mechanical 

 and chemical industries were start- 

 ing upon a new development, 



