392 
Eeport of the Chemist op the 
As the proportion of the rainfall evaporated is greatest during the 
summer, the monthly distribution of the rainfall has an important 
bearing upon the annual evaporation. Nearly all of the data which 
have been cited in regard to the rainfall and evaporation have been 
derived from stations along the Atlantic coast, and especially from the 
region which contributes to the water supply of Boston. For the 
purpose of comparing the distribution of the rainfall in those sec- 
tions with that in this immediate vicinity, the following table, showing 
the ratio of the monthly rainfall to the mean monthly rainfall, is 
given. The figures for the Atlantic seaboard are the mean of 18 
stations distributed along the coast from Maine to Washington. They 
are for a series of years, none of the stations having less than 20 years 
of record. These, with the figures for Boston and Penn Yan, were 
taken from the Tenth U. S. Census, Vol. XVI, for which they were com- 
piled from the Smithsonian records: 
Atlantic 
seaboard. 
Boston, 
28 years. 
Penn Yan, 
39 years. 
N. Y. Agr. 
Exp. Station, 
Geneva, N.Y., 
5 years. 
January 
0.92 
1.00 
0.58 
0.47 
0.84 
0.94 
0.61 
0.81 
March 
0.96 
0.98 
0.70 
0.52 
April 
1.00 
1.04 
1.01 
0.93 
May 
1.13 
1.10 
1.29 
1.10 
June 
0.96 
0.89 
1.42 
1.36 
July 
1.01 
1.08 
1.33 
2.10 
1.22 
1.10 
1.19 
1.53 
0.92 
0.94 
1.16 
0.99 
October 
0.96 
0.89 
1.10 
0.89 
November 
1.02 
1.03 
0.89 
0.88 
1.06 
1.03 
0.71 
0.42 
An inspection of this table shows a much greater proportion of 
rainfall during the summer months in this section than along the 
Atlantic coast. The per cent of the total annual rainfall received 
during five months from May 1 to Oct. 1 is, for the Atlantic seaboard 
43.67, for Boston 42.57, for Penn Yan 53.25, and for N. Y. Agr. Exp. 
Station 59.0. In consequence of this large proportion of rainfall 
during the summer, the proportion of rainfall evaporated must be 
greater in this locality than in the sections which have been referred 
to. Taking this into consideration, it is probable that even with the 
small rainfall received here the evaporation is not much, if any, less 
than 20 inches. 
