94 Maine; agricuIvTural experiment station. 191 i. 



evaporation depends upon several factors. The most impor- 

 tant of these are : first, the length of time which has elapsed 

 since the egg was laid, second, the humidity and temperature 

 of the surrounding atmosphere and the rapidity with which the 

 air surrounding the egg changes, third, the character of the 

 shell, and, fourth, the amount of exposed surface, i. e., the size 

 of the egg. 



It seemed reasonable to suppose that the loss from evapora- 

 tion would be reduced if the eggs were placed in small sealed 

 jars immediately after laying. A preliminary experiment was 

 performed to compare the loss of weight of eggs so preserved 

 with, that of eggs kept in the open air. September 9, 1910, 

 twenty eggs were brought to the laboratory soon after they were 

 laid. These were all Barred Plymouth Rock eggs laid between 

 8 and 11 o'clock on that morning. No two, of course, were 

 from the same hen. The eggs were divided into two groups 

 of ten each. The first group was numbered from 21 to 30 in- 

 clusive. Each of these eggs was sealed in a half pint Lightning 

 fruit jar. Each jar contained a small amount of cotton to keep 

 the egg from breaking when it was dropped into the jar. The 

 ten eggs of the other group were numbered from 31 to 40 in- 

 clusive, and were placed in a wire basket on the laboratory 

 table. The eggs were weighed* each day for four days, being 

 removed from the jars just before and replaced directly after 

 weighing. The weighing was begun at the same hour and pro- 

 ceeded in the same order (according to serial number of the 

 eggs). At the end of the fourth day the eggs which were 

 sealed in the jars were used in the separation experiment de- 

 scribed later, but the eggs kept in the air were weighed also 

 on the fifth and sixth days. Table No. I shows for each egg 

 kept in the open air, (a) its daily weight; (b) its loss at each 

 weighing from the first weight; (c) its loss in each 24 hours 

 and its mean daily loss for both four and six days; (d) the 

 mean loss for the ten eggs on each day; and (e) the mean daily 

 loss on them for four and for six days. Table No. II gives the 

 same data for the eggs kept in sealed jars except that it in- 

 cludes data for only four days. 



*A chemical balance was used in all the weighing of eggs and parts 

 of eggs. The weights were taken to hundredths of a gram. 



