HEAT OF EVAPORATION OF WATER. 301 
determined in a similar manner. Thus, if m, be the mass evaporated per second by 
the stirrer, we have (using the same notation as before) 
ML — mt, = Qt. + %¢.* 
I spent some weeks over these experiments, but the results were so uncertain, that 
at last I was compelled to give up all hopes of attaining my object by this method. 
I will therefore omit details and give results only. 
TABLE [X.—Evaporation Caused by Passing Dry Gas. 













| Date. ae - malls : Temperature. L. Remarks. 
5) © 5 Bu 5 
September Z : 3 cals ae \ Calorimeter filled with aniline 
cistevrsleli. 1 50:01 566:6 
Preriil 3 50:00 566°3 : ey eer 
Ss lide 2 50°00 567°8 
Mean . 49°82 566°5 
August 29 . 2 39:98 5769 5] 
i 29 al 39:97 572:2 
el 2 39-98 5745 
PEUSIONS 1 39°98 572°9 - Calorimeter filled with aniline 
September 2. 1 39:99 569°8 | 
= 2. 2 39°99 5729 ) 
A 2S 1 39°98 5699 3) 
5 12 3 40:0] 5722 
| = 12 2 40:00 569°4: Oil in calorimeter 
+ 13 Z 39°98 - 572°7* *Nitrogen passing 
Mean. 39°99 572°4 
| August 19 . If 24°97 582°6 a) 
a5. AG 1 24°96 580°6 | 
 ononeietie e'4Y 1 24-96 584-2 
53 cig22 1 24°96 o81°7* *Nitrogen passing 
op ee 1 24-97 580°0 >Calorimeter filled with aniline 
em er. aes 1 24°97 584°7 : 
ayaa. 1 24°95 5815 
sy ey 1 24-95 580°3 
| # 128 1 24°95 581-4 J) 
‘Mean .| 24:96 | 581-9 




* %q in this case = Ca, {(0', — 0) + (d' —d")} + C'o, (T’ — T") where C's, is the ‘mean mass” of 
the water in the flask, and T’ and T” the initial and final temperatures of that water as indicated by the 
flask thermometer G, i 
