on the Subject of Heat. 2 1 9 



3d. In regard to the objection made to the experi- 

 ment which was undertaken with a view of determin- 

 ing whether a change had taken place in the capacity 

 of the metallic dust for heat, this can very readily be 

 answered, and in such a way that nothing, it seems to 

 me, can be said against it. If the temperature of boil- 

 ing water were really sufficient to give to these small, 

 forcibly condensed particles of metal the quantity of 

 heat necessary to bring them back to their original con- 

 dition as far as their capacity for heat is concerned, then, 

 as the water by which the apparatus was surrounded 

 finally began to boil, they must, without doubt, have 

 taken the necessary amount of heat from this water. If, 

 now, these particles of metal received finally from the 

 water the caloric which in the beginning they imparted 

 to it, the question arises, whence came the caloric which 

 served to heat, not only the water, but also the metal 

 and the objects immediately surrounding it ? 



I am far from desiring to deceive any one by an im- 

 posing arrangement of facts ; but the facts in my ex- 

 periments were so very striking that it was altogether 

 impossible for me to help instituting comparisons and 

 making calculations with regard to them which would 

 make them clear, especially to those not yet sufficiently 

 acquainted with such investigations. 



I will now close my remarks with an entirely new 

 computation. I will show whether it is probable 

 that the metal could supply all the heat which was pro- 

 duced by friction in the experiment in question. If 

 we are to make this supposition, we must, in the first 

 place, allow that all the heat came directly from the 

 particles of metal which were separated from the solid 

 mass of metal by the friction ; for, since the mass re- 



