TABLE OF CONTENTS. Xlll 



254. Data as to electric battery cells : 



(a) Double fluid batteries 246 



(b) Single fluid batteries . . . ' '. 247 



(c) Standard cells 247 



(d) Secondary cells ... 247 



255. Thermoelectric power of various metals and alloys . . . . .248 



256. " " " " alloys 249 



257. Thermoelectric neutral point of various metals relative to lead . . . 249 



258. Specific heat of electricity for metals ' . 249 



259. Thermoelectric power of metals and solutions -250 



260. Peltier effect, Jahn's experiments . . 250 



261. " " Le Roux's " 250 



262. Conductivity of three-metal and miscellaneous alloys ...... 251 



263. " " alloys 252 



264. Specific resistance of metallic wires, various dimension units . . . .254 



265. " " " metals, various authorities 255 



266. " " " " and alloys at low temperatures 256 



267. Effect of elastic and permanent elongation on resistance of metallic 



wires 258 



268. Resistance of wires of different diameter to alternating currents . . . 258 



269. Conductivity of dilute solutions proportional to amount of dissolved salt 259 



270. Electrochemical equivalent numbers and densities of approximately nor- 



mal solutions 259 



271. Specific molecular conductivities of solutions 260 



272. Limiting values of specific molecular conductivities 261 



273. Temperature coefficients of dilute solutions 261 



274. Various determinations of the ohm, the electrochemical equivalent of 



silver and the electromotive force of the Clark cell . 262 



275. Specific inductive capacity of gases 263 



276. " " " " solids 264 



277. " " " " liquids 265 



278. Contact difference of potential, solids with liquids and liquids with 



liquids in air 266 



279. Contact difference of potential, solids with solids in air 268 



280. Potential difference between metals in various solutions ..... 269 



281. Resistance of glass and porcelain at different temperatures .... 270 



282. Relation between thermal and electrical conductivities : 



(a) Arbitrary units 271 



(b) Values in c. g. s. units . . . 271 



(c) Berget's experiments 271 



(</) Kohlrausch's results 271 



283. Electrochemical equivalents and atomic weights of the chemical ele- 



ments . 272 



284. Permeability of iron for various inductions 274 



285. Permeability of transformer iron : 



(a) Specimen of Westinghouse No. 8 transformer 274 



(*) " " "6 " ....... 275 



