EXPERIMENTS WITH FLAX ON BREAKING. 7 
nearly normal temperatures prevailed and crops developed and ma- 
tured more normally. 
PRECIPITATION. 
The seasons of 1914 and 1915 were unusually rainy. While 
higher annual precipitations are on record for this area, the seasonal 
(April 1 to August 31) precipitation in 1915, 19.52 inches, is the high- 
est recorded, while the precipitation of 10.68 inches in June. 1914, 
is the highest on record for any single month in the 43 years. At 
no time in either season was there any lack of moisture, while the 
cool, cloudy weather of August, 1915, delayed ripening almost a 
month. In 1916 the annual precipitation was 2.34 inches below the 
40-year mean, while the seasonal was 1.45 inches below the mean 
seasonal. Fair distribution with abundant subsoil moisture matured 
satisfactory crops, although the yields were not as large as in the two 
previous seasons. Table II shows the precipitation for these years 
by months in comparison with the 40-year average. 
Table II. — Precipitation, at Mandan, X. Dak., for the years 1914, 1915, and 1916 com- 
pared with the 40-year average at Bismarck, N. Dak., from 1874 to 1913, inclusive. 
Period and year. 
Precipitation (inches). 
Jan. 
Feb. 
Mar. 
Apr. May June July Aug. , Sept. 
1 i 1 
Oct. 
Nov. 
Dec. 
Total. 
40-year average . . . 
1914 
1915 
1916 
0.53 
.07 
.07 
.28 
0.49 
.05 
Ti 
.09 
1.01 
1.89 
.30 
1.88 
1.69 
1.55 
1.11 
.93 
3-44 
3.57 
4.98 
1.69 
3.62 
10.68 
6.32 
2.25 
■ 
2. 15 2. 00 
1.35 | 1.89 
6.48 j .63 
3.55 2.04 
1.29 
1.24 
1.84 
. .92 
1.01 
.90 
1.85 
.27 
0.61 
.31 
.34 
.07 
0.57 
.37 
.14 
1.10 
17.41 
23. 87 
24.06 
15.07 
iT = trace. 
EVAPORATION. 
Evaporation was high in 1914, as the result of a combination of 
high temperature and relatively high wind velocity. In 1915 the 
evaporation was far below the 3-year average, owing to the cool, 
cloudy weeks of August and September. In 1916 a drier atmosphere 
combined with higher temperatures resulted in an increased evapora- 
tion compared with that of 1915. The average mean and maximum 
temperatures were lower than in 1914, and this appears to have re- 
sulted in holding evaporation below the record in that year. This 
was fortunate, for the crops were several times in danger of being 
dried too quickly at critical stages in their development. 
Hot, drying winds of two and three days' duration occurred in 
July and August in both 1914 and 1916. In 1914 little damage was 
done, because of adequate moisture. The yields in 1916 doubtless 
were reduced somewhat because of premature ripening. Little 
difference in the seasonal average wind velocity is apparent, although 
the average annual for 1915 is below the 3-year average. 
