1 4 Introduction 



We have next the account of the experiments, the order of which is 



No. 7 Figs. 12 to 13 Exp. i. and n. Arts. 217 to 235 



No. 9 Figs. 14 19 Exps. in. to vm. Arts. 236 ,, 294 



No. 10 Figs. 20 30 Arts. 295 385 



No. 8 Fig. 31 Arts. 386 394 



The style in which these papers are written leaves no doubt that they 

 were intended to form a book, and to be published. They are given here 

 without any alteration except in the case of a few abbreviations the meaning 

 of which is either obvious or is explained in some other part of the MS. 

 I have also divided them into articles for the sake of more convenient 

 reference. All additions to the MS. are enclosed in square brackets. 



After this I have placed the paper on the Torpedo from the Philo- 

 sophical Transactions for 1776. This, I think, is the whole of the "work" 

 which is extant, but it is by no means a complete account of Cavendish's 

 electrical researches. There are three forms in which Cavendish recorded 

 the results of his experiments : 



1st. A Journal containing notes of every observation as it was made, 

 with the particulars of the experiments, and measurements of the 

 apparatus. 



2nd. "Results," containing a comparison of the different measures of 

 quantities as recorded in the Journal, and a deduction of the most probable 

 result. See Arts. 647-696. 



3rd. An account of the experiments written for publication. 



I have reproduced the journals for 1771* and 1772! entire, because 

 they form a good example of Cavendish's method of work, and because 

 they contain all the data of some of the most important electrical measure- 

 ments. 



The journal for 1773 j is much larger than the others, and gives an 

 account of many interesting and important researches. 



Many pages of this journal, however, are filled with the details of the 

 experiments for the comparison of the coated plates which Cavendish used 

 as standards of capacity. These experiments differ in no respect from those 

 in the former journals, and all the conclusions which Cavendish deduced 

 from them are stated by himself in the " Results." I have therefore thought 

 it best to omit them from the journal, but to retain Cavendish's heading 

 of each experiment and its date when known, and to make the numbers 

 of the omitted articles run on continuously with those retained. 



Many of the entries in the journals give the day of the week and of 

 the month, but very few of them give the year. I have therefore ascer- 

 tained in what years the stated days of the week and month coincided, 

 and have inserted the most probable year within square brackets. It thus 

 appears that the journal entitled "Experiments in 1773" begins with 

 * Arts. 438 to 465. f Arts. 466 to 493. J Arts. 494 to 580. 



