278 Of the Propagation of Heat 



in a tea-kettle, it was not quite boiling hot when it 

 was poured into the jar. After it had been in the jar 

 one minute I plunged a thermometer into it, and found 

 its temperature to be at 180. 



After 12 minutes had elapsed, its temperature at the 

 depth of one inch under the surface was 170. At the 

 depth of seven inches, or one inch above the surface of 

 the ice, it was at 169^, while at only f of an inch lower, 

 or ^ above the surface of the ice, its temperature was 



40. 



When 20 minutes had elapsed, the Pleat in the water 

 at different depths was found to be as follows : 



Immediately above the surface of the ice . . 40 



At the distance of an inch above it . . .46 



At i inch 130 



At 3 inches ........ 159 



At 7 inches ....... 160 



When 35 minutes had elapsed, the Heat was as fol- 

 lows : 



At the surface of the ice 40 



an inch above it . . . ?6 



1 inch above it . II0 



2 inches 144 



3 inches ..... 1 4$ 



5 inches ...... 148^ 



7 inches . *49 



At the end of one hour the Heat was as follows : 



At the surface of the ice ... . . 4 



1 inch above it ..... So 



2 inches ...... IJ 8 



3 inches ..... 128 



4 inches ..... I 3 

 7 inches ...... J3 1 



