CONTENTS. xvii 



BOOK IV. 

 OF ELECTRICITY. 



C M A P. I. page 297. 

 Hiftory of Difcoveries relative to Eledlricity. 



Origin of the Name. Hdkv far Electricity was kncvjn- to the An- 

 tients.Mr. Boyle. Otto Guericke. Dr. Wall. Mr. Ha-ivAfiee. 

 Mr. Grej's Difcoveries. M. Du Fay's. Subfequent Difcoveries of 

 Mr. Grey. Improvements of German Philofophers. Ley den Phial. 

 Electrical Battery. Spirits fired by Electricity conduced through 

 the River Thames. T<wo Species of Eleilricity difcovered. Dr, 

 Franklin's great Difcoveries. 



CHAP. II. page 307. 

 General Principles of Eledtricity. 



Analogy between Caloric, or Fire, and the electrical Fluid. The Argu* 

 ments on the contrary Side. '-Conjectures concerning the Nature of 

 this Fluid. -Means of producing tlcttrical Phenomena. Conductors 

 and Non-conductors. Inftruments employed in Electricity. 



CHAP. III. page 323. 



Of the Vitreous and Refmous, or Poiitive and Negative Electricity. 



Diliinction in the attractive Powers of certain Electrics, Theft 

 Effects found to defend not on the Nature of the Sutftance, but the 

 Roughnefs or Smocthnefs of the Surface.* Theory of Two dijtinft 

 Fluids. Franklin's Theory. Difficulties attending it, 



CHAP. IV. page 329. 

 The Leyden Phial, Electrical Battery, and other Parts of the 



Apparatus. 



Theory of the Leyden Phial. Its Ufe in EleSrichy. Defcription of 

 the beft Apparatus of this Kind. The Charge refides in the Glafs. 

 Curious Experiments -u-ith the Leyden Phial. Electrical Baftery. 

 Injlruttions relative to it. Experiments nuilh the electrical Bat~ 

 ttiy. Electrical Bells. Electrophar us. Electrometer. 



CHAP. V. page 338. 



Eledlrical Phenomena. 



Phenomena of Attraction and Repuljion. Electrical Atmofphere. Dif- 

 ferent Effects on different Subjtances. Eleftrical Cohefion. Experi- 

 ments on Silk Stockings.' On the Evaporation of Fluids. yegeta- 

 tion. Animal Per/fir ation. Inflammation of Spirits. Animals 

 killed by Electricity. Curious Phenomena in vacua.* Recapitulation 

 cf Principles. 



VOL, I. a CHAP, 



