xviii Contents 



ARTICLES 



Theory of compound plates 379 



Experiments with compound plates of glass ........ 380 



Experiments with glass and rosin .......... 381 



Charge of hollow cylinders of glass 382 



Table of results with cylindric vials .......... 383 



Discussion of the results 3^4 



Appearance of the three green cylinders 385 



(4) REPULSION AS SQUARE OF REDUNDANT FLUID 



From MS. No. 8 



The repulsion between two bodies electrified to the same degree ought, by the theory, 



to be proportional to the square of the quantity of redundant fluid . . . 386 



Experiment to test the theory. (Fig. 31) 38? 



Comparison of the force required to produce an equal divergence of the two electro- 

 meters ............... 388 



The Leyden jars 389 



Method of the experiment 39 



Discussion of the experiment ........... 391 



Method of preventing the vibration of the straws .... . 392 



No sensible error due to leakage 393 



Effect of want of conductivity of the straws 394 



SECOND PUBLISHED PAPER ON ELECTRICITY P . 194 



AN ACCOUNT OF SOME ATTEMPTS TO IMITATE THE EFFECTS 

 OF THE TORPEDO BY ELECTRICITY 



From the Phil. Trans, for 1776 (pp. 196-225) 



Walsh's experiments on the Torpedo 395, 396 



Shock given by the Torpedo under water 397 



Electric resistance of salt and fresh water, and of iron wire .... 398 



Lines of flow of the discharge of the Torpedo ...... 399> 400 



Conditions requisite for a spark and for attraction and repulsion . . . 401-408 



Artificial Torpedo 409, 410 



The battery and its charge 411-413 



Mode of charging the battery 414 



Shocks in air and under salt water. Law of divided currents .... 415-420 



Torpedo in a basket ; in sand ; shock through wet shoes and through net . . 42 1 -424 



Why the Torpedo gives no spark 425-435 



Structure of the electric organ .......... 436 



Shock through a chain without any light 437 



EXPERIMENTS IN 1771 ... P . 211 



From MS. No. 12 



ist Night 438 



2nd Night 439 



3rd Night ............... 440 



Two pairs of large corks made, one four times as heavy as the other. Measurement of 



capacity of vial by touching eight or nine times with coated plate and wire . . 441 

 Thickness. 



C -0601 1 



Three coated plates .... 442 



D -05908 



F -05914 



