444 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



TABLE VI. 

 Expansion of Ethyl Ether in the Superheated State. 



pressure, I removed the flame from beneath the water-bath in order to allow the 

 temperature of the ether to return to 35° C, expecting to observe the decrease 

 in volume corresponding to this decrease in temperature. But, instead of cool- 

 in"- quietly down to its former temperature, the ether suddenly changed into 

 vapor shortly after the flame had been removed. It occurred to me that the 

 reversing of the temperature was the cause of this sudden vaporization. I then 

 adopted the method described above, and no further difficulty was encountered 

 from these sudden vaporizations. It is seen that by this method I returned to 

 the unsuperheated state by an increase of pressure instead of by a decrease of 

 temperature. 



I do not consider that the four observations which I made justify me in saying 

 that the reversal of the temperature was the true cause of these sudden vaporiza- 

 tions, but as we do not fully understand the conditions of equilibrium of the 

 superheated liquid, it seems best to record these unexplained observations. 



