146 



Experimental Investigations 



melting ice, fresh portions of ice were added to it, from 

 time to time. 



The thermometers are graduated to Fahrenheit's 

 scale, the freezing point being marked 32, and that of 

 boiling water 212. 



As the first and most important object I had in view 

 was to learn at what temperature the three thermome- 

 ters would become stationary, I did not very carefully 

 notice the progress of the thermometers toward this 

 point ; but as soon as they appeared nearly stationary, 

 I observed them with the greatest attention for near 

 half an hour. 



To distinguish the three thermometers, I shall call 

 that nearest the boiling water B, that in the centre C, 

 and that nearest the cold water D. 



The following are the progress and results of an ex- 

 periment made the 28th of April, 1804, the tempera- 

 ture of the air being 78 of Fahrenheit. 



Before I proceed to examine more minutely the re- 

 sults of this experiment, I will endeavour to show 



