FIRST METHOD. 



A piece of clear ice, in a cubical form, measuring 5 cm. on a 

 side, was weighed in a small wire holder so arranged that the 

 ice was exposed to the air freely on all sides. After each weigh- 

 ing the ice with holder was taken from the balances and sus- 

 pended in the free atmosphere. The temperature was carefully 

 taken, estimating to tenths of a degree, and the barometric pres- 

 sure estimating to hundredths of an inch. These readings on 

 weight, temperature, and pressure were taken and recorded 

 every hour during the day from 9 a. m. to 4 p. m. for seven 

 successive days. This experiment was performed in the attic 

 of the Camden High School building. 



A maximum and minimum thermometer hung near the piece 

 of ice and from this the temperatures were taken for each night 

 excepting the first February 28. 



The average evaporation per hour was found each night 

 excepting March 2. It was found that this hourly evaporation 

 during the nights was considerably less than during the days. 



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