CAPILLARY MOVEMENT OF SOIL MOISTURE. 
57 
of soil is farther away from the water and gravity would tend to 
hold the moisture in the lower layer. Secondly, evaporation from the 
surface would tend to further reduce the moisture at and near the 
surface. Thus the laws of physics would indicate a lower percentage 
of moisture toward the top of the flume than near the bottom. There 
were, however, several instances where this relationship was inter- 
changed, and more especially was this noticeable during the winter of 
1916-17. When this interchanged relationship in the distribution of 
moisture was observed so frequently during the spring of 1917 as to 
almost preclude the probability of error from sampling, it seems 
evident that the unlooked-for distribution of moisture was the result 
of some natural condition. It soon became apparent that the top part 
of the flumes showed the greater percentage of moisture during only 
that time of the year when the air temperature Avas or recently had 
been below 30°. In looking back over the results of the preceding 
winter, this same condition was found. When these facts became 
evident it was so late in the season that there was no opportunity to 
prove the matter beyond a question of doubt. For this reason a few 
of the samples, with percentage of moisture and air temperature, are 
given in Table 42 for what they may be worth. 
Table 41 
Soil-moisture distribution and air temperature 
Date. 
Distance. 
Flume. 
Percentage of 
moisture. 
Temperature for 
week preceding. 
Top Bottom 
5 inches. 5 inches. 
Maxi- 
mum. 
Mini- 
mum. 
Mar. 5, 1917.. . 
Mar. 16, 1917.. 
Apr. 21, 1917.. 
Inches. 
21 
38 
62 
92 
44 
128 
201 
32 
68 
104 
140 
190 
32 
72 
56 
90 
Per cent. 
31.53 
27.44 
26.33 
23.37 
29.11 
27.78 
41.13 
28.75 
26.45 
25.75 
Per cent. 
29.32 
36.30 
25.66 
23.67 
26. 83 
26.64 
28.46 
30.44 
26.38 
25 . 45 
70° 27° > 
i 
1 
95 
..;. ro :. .;.. 27 " 
92 
77° 1 26° 
24.30 i 24.60 
17.83 1 19.32 
28.31 J 29.90 
20. 61 I 22. 00 
25.13 25.47 
101 
82° ; 32° 
i 
At a distance of 82 inches in flume 93 there Avas taken on March 
20 a set of samples dividing the boring into four samples, each 
containing 2J inches of soil in depth, and the folloAving results ob- 
tained : 
In the top sample, 28.96 per cent. 
In the second sample, 27.56 per cent. 
In the bottom sample, 26.60 per cent. 
In addition to the samples given above there are several others 
showing similar results. There are some samples taken at the same 
