1 2 Introduction 



The papers belonging to the years 1771, 1772 & 1773 consist of six papers on 

 Mathematical Electricity, nine experimental papers, one of Diagrams and 

 Figures, the remainder are of a miscellaneous character, and contain some 

 interesting Notes and Remarks and Thoughts on Electricity. 



On examining the 20 parcels of manuscripts I found their contents to 

 be as follows : 



No. i. MS. pp. i-io. Apparently an early form of the "Preliminary Propositions." 



No. 2. MS. pp. 1-31. Draft of "Preliminary Propositions" as far as Prop. xxvu. 



No. 3. MS. L. 3 to L. 23. Contains the same propositions in a less complete form 



and not numbered, also two drafts of the propositions oh coated plates, each 



12 pp., and 38 loose pages of drafts of propositions, and jottings of algebraical 



calculations. 



No. 4. MS. pp. 1-48. The fair copy of the " Preliminary Propositions." Props. 



xxix. to xxxvu. Refers to figs. I to 10 of No. 15. See Arts. 140-174. 

 No. 5. MS. pp. 1-20. "Appendix." Refers to fig. n. See Arts. 175-194. 

 No. 6. "Computations for explanation of experiments." 

 MS. pp. 1-15. Drafts of the propositions. 



16 pages of computations. "B. 17." Charge of a sphere within a con- 

 centric sphere. [This is placed here as a note to Art. 335.] 



"Attractions of elect, bodies more accurate," pp. 1-4. 



No. 7. MS. D. i to D. 13. Fair copy of First and Second Experiments. Refers to 

 Figs. 12, 13. See Arts. 217-235. 



Draft of ditto marked "DIA." 



No. 8. MS. pp. 1-7. Refers to Fig. 31. See Arts. 386-394. 

 No. 9. MS. pp. 151. Continuation of Experiments. See Arts. 236-294. 

 No. 10. MS. pp. 52-132. Part* of Experiments. See Arts. 295-385. 



No. n. MS. pp. 1-8. IA. p. 10 A. 8, 9. p. 29 A. p. 32 A. i and 2. pp. 57-64. 

 pp. 85, 86. pp. 91-96. pp. 103-108. pp. 119-126. pp. 133-138. pp. 141, 142. 

 pp. 156-166. 



All drafts of portions of the Account of Experiments. 

 No. 12. "Experiments 1771," MS. pp. 1-24. See Arts. 438-465. Also 14 loose sheets 



of calculations and measurements. 

 No. 13. "Experiments 1772," MS. pp. 1-29. See Arts. 466-493. 



M. i to M. 13. Measurements of glasses, &c. See Arts. 592-595. 

 No. 14. Experiment 1773, MS. pp. 1-135. See Arts. 494-580. 

 Index to elect, exper. 1773, pp. 1-8. See Contents. 

 Dimensions of trial plates, 4 pages. 







No. 15. Figures and Diagrams. 



i to 10 refer to Preliminary propositions No. 4 



II Appendix No. 3 



!2 ,, 13 ,, ,, Exp. i No. 7 



14 ,, 19 ,, ,, Experiments, Part i No. 9 



20 ,, 27 ,, ,, ,, Part 2 No. 10 



30 ,, ,, Electrometer No. 9 



31 ,, ,, Repulsion No. 8 



* So in MS. 



