464 EUDOLP JULIUS EMANUEL CLAUSIUS. 



peratur," * and " Ueber die theoretische Bestimmung des Dampf- 

 druckes und der Volumina des Dampfes und der Flussigkeit " (two 

 papers), f 



Another matter in which Clausius showed his originality and power 

 was the vexed subject of electrodynamics, as treated in his memoir, 

 '' Ueber die Ableitung eines neuen electrodynamischen Grundge- 

 setzes."$ Various points in the theory of electricity in which the 

 principles of thermodynamics or of molecular science were involved, 

 had previously been treated in different papers, of which the earliest 

 appeared in 1852, § while the doctrine of the potential (electrical and 

 gravitational) was treated in a separate book, which appeared in 1859, 

 with the title, " Die Potentialfunction und das Potential, ein Beitrag 

 zur mathematischen Physik." This subsequently went through several 

 editions, in which it was revised and enlarged. All these subjects, with 

 others, were brought together in a single volume, " Die mechanische 

 Behandlung der Electricitat," which appeared in 1879, forming the 

 second volume of his ** Mechanische Warmetheorie." || Later papers 

 on electricity related to the principles of electrodynamics,^ electrical 

 and magnetic units,** and dynamo-electric machines.ft 



The Royal Society's catalogue of scientific papers, and the excellent 

 indices to the Annalea der Physik und Chemie, in which Clausius's 

 work usually appeared, render it unnecessary to enumerate in detail 

 his scientific papers. The list, indeed, would be a long one. The 



* Wied. Ann., vol. ix. p. .337 (1880). 



t Ibid., vol. xiv. p. 279 and p. 692 (1881). 



} Crelle's Journal, vol. Ixxxii. p. 85 (1877). 



§ " Ueber das mechanische Aequivalent einer electrischen Entladung und die 

 dabei stattfindende Erwarniung des Leitungsdrahtes." Pogg. Ann., vol. Ixxxvi. 

 p. 337. " Ueber die bei einem stationaren electrischen Strome in dem Leiter 

 gethane Arbeit und erzeugte Warme." Pogg. Ann., vol. Ixxxvii. p. 415 (1852). 

 " Ueber die Anwendung der mechanischen Wiirmetheorie auf die thermoelec- 

 trischen Erscheinungen." Pogg. Ann., vol. xc. p. 513 (1853). "Ueber die 

 Electricitatsleitung in Electrolyten." Pogg. Ann., vol. ci. p. 338 (1857). 



II The first volume of this work appeared in 1876, and contained tlie general 

 theory with the more immediate consequences of the two fundamental laws. 

 The tiiird volume has not yet appeared, but it is expected very soon, edited by 

 Professor Planck and Dr. Pulfrich. In a certain sense this work may be re- 

 garded as a second edition of an earlier one (1864 and 1867), which consisted 

 of a reprint of papers and had the title " Abhandlungen iiber die mechanische 

 Warmetheorie." 



IT Wied. Ann., vol. x. p. 608; vol. xi. p. 604. 

 ** Ibid., vol. xvi. p. 529 ; vol. xvii. p. 713. 



tt Ibid., vol. XX. p. 353 ; vol. xxi. p. 385. 



