thus proving that the amount of evaporation is proportional to 

 the area of the exposed surface. 



The second table shows, as the first did, that the amount of 

 evaporation increases as the temperature increases. 



SECOND METHOD. 



In this method the ice was placed in a wire cage suspended 

 from a coiled spring. By use of an index and scale the rise of 

 the ice due to evaporation could be accurately measured. A box 

 3x1x^/2 was placed outside the laboratory window, and in this 

 box was placed the barometer, thermometer, and wire suspended 

 from the top. The velocity of the wind was estimated accord- 

 ing to directions given in Ward's Laboratory Exercises in 

 Meteorology. 



By this method it was possible to make all readings through 

 the window and thereby allow no heat to reach the snow or ice 

 from the laboratory. The window was on the north side of the 

 building where the sun did not strike the box during the day. 

 As only the side of the box facing the window was taken out it 

 was not possible for the wind to strike the apparatus with much 

 force ; but a free circulation of air was obtained. 



