BOILING. 



81 



192. Water begins to boil when it is 



What is the 



boiling point heated up to 212 ; alcohol, at 173 ; and 

 Of W ethcr ' ? ether, at 96. As the proper temperature is 

 Of alcohol ? fi rst reached at the bottom of the vessel, 

 near the fire, the formation of bubbles begins there ; 

 and as the surplus heat comes in below, they continue 

 to be formed at this point. 

 Every liquid has its own boil- 

 ing point. 



How much 193. EXPAN- 



stcam do cubic SION m BOIL ING. 



inches of wa- 

 ter, alcohol, A cubic inch of 



and ether re- , ., -, . 



spcctiveiy pro- water boiled in 

 dnce? an O p en vessel, 



produces 1696 cubic inches 

 of steam. A drop one-tenth of an inch in diameter, 

 would make enough to fill a vessel of the diameter 

 of one and a fifth inches. A cubic inch of alcohol 

 produces about 500 cubic inches of alcohol vapor ; one 

 of ether about 250. The ether vapor is most dense, 

 that of alcohol next, and the steam 

 least so. 



194. DISAPPEARANCE OF 



HEAT IN BOILING. If a 



thermometer be held in 



boiling water, it indicates 

 a temperature of 212 F. Continue 

 the fire, and although heat constantly 

 passes up into the water through the 

 bottom of the vessel, it grows no hot- 

 ter. The steam which is produced has 

 4* 



What is said 

 of the disap- 

 pearance of 

 heat in boiling? 



