On Evaporation. 5gt 
the phial into the scale again; took out 40 grains 
from the opposite scale, and waited till the equi- 
librium was restored: this was in 8 minutes 6 
seconds. The air was 50°, and the ether at 
first 50°; but it rapidly sunk, as was found by 
dipping a very small bulbed thermometer into 
it, to. 28°. In a window with a_ moderate 
breeze. 
2and 3. Repeated the experiment, in the 
same circumstances, except the evaporating ves- 
sel, which was now porcelain, and 23 inches 
diameter. Lost 40 grains in 3 minutes.. Ther. 
mometer sunk from 50 to 30°... The two experi. 
ments made this way did not differ above one or 
two grains. 
_ These results reduced toa vessel. of 3? inches 
in diameter give 
1st. Experiment, loss 17 grains. per - minute; 
2&3 — 222 
. The reason why the result in the. first-experi- 
ment was something less than in the other two, 
was evidently owing to the circumstance of its 
longer duration, by which the ether was the 
greater part of the time in a low temperature, 
and consequently evaporated less\—The ether 
used boiled at 102°. At 50° it was therefore in the 
capacity of water at 160°, But water at 160°, at most 
loses only 17 or 18 grains per minute, and less 
VOL, V. M M 
