and on Lite Expansion of Moist Air. 429 



drj^ air, as not ditfcring materially, as far as 

 respects the present subject, from my own ; 

 I take the force of vapour from my table 

 (Memoirs vol. 5, part 2. page 559) from which 

 that of Sclmiidt no where differs widely. I 

 calculate from 1 part of air saturated with 

 moisture at the temperature of S2** in order to 

 compare with Schmidt, and for every 5° of 

 Reaumur's scale. The boiling point is sup- 

 posed in mine to be taken at 30 inches of the 

 barometer, though his istakenat 28 French inch, 

 which is somewhat lower. The theorem from 

 which I calculate is given at page 572 of the 



Memoirs above quoted; namely, -^ — -JH^ ^ 



space occupied by air in contact with heated 

 water, for any temperature; where f= force 

 of vapour of the given temperature in inches 

 of mercury : the dry air in I measure saturated 

 at 32"* is equal ,9933. — I have rejected Deci- 

 mals in both tables, beyond the fourth place. 



3h 



