[From U Pnendutgt of the Cambridge Philosophical Society. Vol. HI. Pt. in.] 



LXXXVII. On the Unpublished Electrical Papers of the Hon. HENRY CAVENDISH. 



CAVKKDISH published only two papers relating to electricity, "An attempt 

 to explain some of the principal Phenomena of Electricity by Means of an 

 Ebtftic Fluid" (Phil. Trans. 1771, pp. 584 677), and "An account of some 

 Attempts to imitate the Effects of the Torpedo by Electricity" (Phil. Trans. 

 for 1776, pp. 196 225). He left behind him, however, some twenty packets 

 of manuscript on mathematical and experimental electricity. These were 

 placed by the then Earl of Burlington, now Duke of Devonshire, in the 

 h^iwJa of the late Sir William Snow Harris, who appears to have made "an 

 abstract of them with a commentary of great value on their contents." This 

 was sent to Dr George Wilson when he was preparing his Life of Cavendish 

 i I I'.'rtfo of the Cavendish Society, Vol. I. London, 1851). It was afterwards 

 returned to Sir W. S. Harris, but I have not been able to learn whether 

 it ia still in existence. The Cavendish manuscripts, however, were placed in 

 my hands by the Duke of Devonshire in 1874, and they are now almost 

 ready for publication. 



They may be divided into three classes : 



(A) Mathematical propositions, intended to follow those in the paper <>t 

 1771, and numbered accordingly. Some of these are important as shewing the 

 clear ideas of Cavendish with respect to what we now call charge, potential, 

 and the capacity of a conductor ; but the great improvements in the mathe- 

 matical treatment of electricity since the time of Cavendish have rendered 

 others superfluous. 



We come next to an account of the experiments on which the mathe- 

 matical theory was founded. This is a manuscript fully prepared for the press, 

 and since it refers to the second part of the published paper of 1771 as "the 



