CONTENTS. 



Xlll 



Capillary action in narrow tubes and between floating 



bodies, ... 251 



"Wicks: capillary siphons, .... 253 



CHAPTER XVIII. Soap Bubbles and Films, . . . 254-262 



Analogy between a soap bubble and an india-rubber balloon, 254 



Do. do. flat soap film and a stretched membrane 3 255 



Soap solutions for film and bubbles, . . . 256 



Tenacity of thin films : soap film spring balance, , I 257 



Annular soap films, . . ... . . 258 



Soap bubbles will not readily touch : effect of electrifica- 

 tion, . . . .. . . 258 



Soap bubble balloons : one bubble inside another, . 259 



Soap bubble floating on an atmosphere of carbon dioxide, 261 



7. EFFECTS OF HEAT UPON BODIES, OTHER THAN CHANGE of 



STATE AND PRODUCTION OF CHEMICAL ACTION, . 262-287 



CHAPTER XIX. Expansion and Contraction, -. . 262-271 



Expansion of metals and other solids : rate of expansion 



differs, . . . . . . . 262 



Measurement of expansion, .... 263 



Curving of compound bars : Breguet's thermometer, . 265 



Expansion of liquids, ..... 266 



Irregular expansion of water: point of maximum density, 266 



Expansion of gases : gas engines, . . 267 



Air thermometer, - . . . . . 268 



Ascending currents of hot air : motion produced, . 269 



Differential air thermometers : Leslie's : Matthiessen's, 270 



CHAPTER XX. Conduction and Convection of Heat, . 271-281 



Convection currents : heating and cooling buildings, &c., 272 



Ice chests : Norwegian stoves : functions of clothing, . 273 



Conduction of heat : solids differ in conductivity, . 274 



Wooden handles for hot tools, . . . . 275 



Wire gauze and flames : safety lamps, . . . ' 276 



Water possesses very low conducting power, . . 278 



Boiling water and ice contained in same vessel, . . ' 279 



Thermoelectric action, ...... 281 



CHAPTER XXI. Measurement of Heat. Specific and Latent 



Heat, .... . . . . 281-287 



Distinction between temperature and quantity of heat, . 282 



Capacity for heat, ..... 282 



