INDEX. 
313 
Transpiration apparatus described, 212, 211. 
manipulation of. 255. 
Transpiration data vitiated by condensation of 
gas, 301. 
devices for rapid, at high temperatures, 284. 
differential measurement of, 293. 
during long - intervals, 293. 
Transpiration formula', conditions of, 252. 
for two cold ends, 252. 
for differential apparatus and cold ends, 254. 
Transpiration in wide tubes, data for, 287, 288. 
effect of pressure on, in wide tubes, 295. 
in wide tubes influenced by temperature, 
297. 
in wide tubes, general remarks on, 300. 
in glass tubes, 298. 
in silver tubes, 299. 
in platinum tubes, 300. 
measurement of capillary radii, 255. 
not subject to Poiseuille-Meyer's law, 284. 
Transpiration pyrometry, capillary apparatus 
for, 215. 
formula? for, 281. 
advantages of, 281. 
re suits for, 282. 
practical remarks on, 302. 
forms of, 303. 
protection of, 305. 
Transpiration under variable pressure, 287. 
Troost, studies dissociation of iodine, 30. 
measures boiling point of selenium, 34,35. 
diffusion pyrometer, 39. 
boils selenium in glass, 89. 
boiling point of selenium, 121. 
on expansion of gases, 248. 
Tubes, capillary, of metal, 169. 
Turner on transparency of metals, 164. 
Vacuum boiling points of metals, 95. 
Vapor bath, mercury, data for large, 69. 
of zinc, data for large, 70. 
Vapor bath, small form of, for low tempera- 
tures, S4. 
for mercury, 84. 
for sulphur, 85. 
forms of, for high temperatures, 90. 
Vapor bath, of mercury, constant temperature 
of, 105. 
of sulphur, constant temperature of, 107. 
of zinc, constant temperature of, 108. 
Vapor baths, liquids for, 119. 
Vapor tension pyrometry, 38. 
Velocity of the mean square, 274. 
Violle, pyrometric work of, 24, 4!). 
measures boiling point of zinc, 35. 
fusion experiments of, 39. 
important calorimetric work of, 41. 
radiation pyrometry of, 44. 
temperature of the sun estimated by, 45. 
silicification of platinum, 187. 
zinc, boiling point of, 235. 
Viscosity, phenomena of, 17. 
of (ire clays, 16. 
of platinum at high temperatures, 293. 
Viscosity of gases, pyrometric use of, 46,248. 
measurement, methods of, 247. 
data for, 258. 
values of, at zero degrees, 271. 
kinetic inferences, 274. 
advantages of an exponential law in, 277. 
Viscosity measurement, errors of, 274, 275. 
temperature coefficient of, 279, 280. 
Vogt. (See Matthiessen.) 
Volatilization, experiments on, 121. 
Volume tube, graded for air thermometer, 210. 
Volumetry of compensator canal, 193. 
of bulbs for air thermometer, 213. 
W. 
Warburg on transpiration of gases, 241. 
temperature coefficient of viscosity of, 279, 
280. 
Water attacks glass at high pressures and tem- 
peratures, 27. 
Water jacket for volumeter, 210. 
Waterston, measures high temperature expan- 
sion of water, 27. 
Weber, H. F., radiation work of, 46. 
Weber, L., electrics of alloys measured by, 145. 
Wedgwood, pyrometer of, 25. 
Weinhold, pyrometric work of, 23, 24, 26, 32, 33. 
oh dissociation pyrometry, 39. 
calorimetric work of, 41. 
studies resistance pyrometer, 51. 
tx - ies Jolly's air thermometer, 208. 
zinc, boiling point of, 235. 
Whitall, Tat urn & Co., apparatus of, 21. 
Wiedemann, E.,on transpiration of gases, 241, 242. 
temperature coefficient of viscosity of, 280. 
Williamson criticises Siemens' pyrometer, 51. 
Wilson, calorimetric pyrometer of, 41. 
Winkler on the graphite pyrometer, 27. 
Wires, platinum, mechanical treatment of, 128, 
133. 
Wirkungssphiire, 274. 
Z. 
Zabel, air thermometer of, 32. 
Zero of temperature coefficient, 161. 
Zinc, boiling point of, 24, 29, 30, 31, 34, 35. 
boiling point, furnace for, 62. 
large vapor bath of, data for, 70. 
large crucible for, 73. 
vapor bath, constant temperature of, 108. 
coincidence of boiling point, data for, 115. 
vapor, calibration in, 122, 123. 
boiling point of, measured, 233, 235. 
