252 Of the Propagation of Heat 



From this experiment it appears that the fibrous parts 

 of stewed apples amount to less than -^-^ part of the 

 whole mass, and there is abundant reason to conclude 

 that the remainder, amounting to ||- of the whole, is 

 little else than pure water. 



Having surrounded the bulb of my cylindrical pas- 

 sage thermometer with a quantity of these stewed ap- 

 ples (the consistence of the mass being such that it 

 shewed no signs of fluidity)^ the instrument was placed 

 in pounded ice which was melting, and when the ther- 

 mometer indicated that the whole was cooled down to 

 the temperature of 32°, the instrument was taken out of 

 the melting ice and plunged into a large vessel of boiling 

 water, and the water being kept boiling with the utmost 

 violence during the whole time the experiment lasted, 

 the times taken up in heating the thermometer from 20 

 to 20 degrees were observed and noted down in a table 

 which had been previously prepared for that purpose. 



This experiment having been repeated twice, and va- 

 ried as often by first heating the instrument to the tem- 

 perature of boiling water and then plunging it into melt- 

 ing ice, and observing the time taken up in the passage 

 of the Heat out of the thermometer, I removed the 

 stewed apples which surrounded the bulb of the ther- 

 mometer, and, filling the space they had occupied with 

 pure water^ I now repeated the experiments again with 

 that liquid. The following tables shew the results of 

 these experiments. 



