CAPILLARY MOVEMENT OF SOIL MOISTUEE. 
55 
Table 38. — Movement of 
moisture at various times, 
in inches. 
Number 
of days. 
Flume. 
70 
71 
i 
3 
5 
10 
15 
20 
30 
Inches. 
23.10 
Inches. 
21.30 
41.70 
54. 60 
61.00 
70.15 
80.05 
41.30 
51.80 
Co. 50 
73.70 
87. 10 
about 9 per cent in favor of the open flume. The rate of movement 
of the moisture in the closed flume is more uniform throughout the 
30 days than that in the open flume. The facts just stated would 
appear to be contrary to what might have been forecast, for the 
reason that evaporation from the open flume would deprive that 
flume of some of the water furnished by the wick. In the closed 
flume practically all of the water furnished by the wick would be 
available for the capillary action of the 
soil. These results would indicate first 
that in the closed flume the soil in the 
flume proper could not use all of the water 
that the wick was capable of furnishing. 
This would indicate a friction factor 
caused either from partially confined air 
or otherwise that would not appear to 
occur in the open flume. It is found in 
the open flume that either from evaporation 
or from a more ready circulation of the 
air the capillary action of the soil within 
the flume was stimulated or that the fric- 
tion was reduced. From observations made in connection with other 
experiments it seems to the writer that the fact of more rapid 
rate of movement in the open flume at the beginning of the experi- 
ment is due to both of these factors. It is known that " trapped " air 
has an effect upon capillary ac- 
tion and that evaporation would 
stimulate the circulation of the 
air. 
Table 39 shows that a rela- 
tively greater quantity of water 
was used by the closed flume dur- 
ing the forepart of the experi- 
ment than was used by the open 
flume. This is a condition which 
would be anticipated, as evapo- 
ration deprives the open flume of 
part of the water furnished by 
the wick. The table shows very clearly that the covered flume does 
not tax the wick to its capacity in furnishing water from the tank to 
the flume proper. 
Table 40 gives the quantity of water required to move moisture 
in the flume an average distance of 1 inch for different periods 
of time. This table does not show effects other than would have 
been anticipated. It is observed that there is a greater use of 
water on the thirtieth day in flume Tl than during the fore part 
Table 89. — Quantity of water used at 
various times, in liters^ and in per- 
centages of total used in SO days. 
Flume. 
Number 
of days. 
70 
71 
70 
71 
Liters. 
Liters. 
Per cent. 
Per cent. 
1 
5 
6 
6 
18 
21 
12 
12 
37 
42 
10 
17 
17 
54 
59 
15 
21 
21 
64 
72 
20 
26 
24 
79 
83 
30 
33 
20 
100 
100 
