469 
sept. s. 1918 Variations in Moisture Content of a Loess Soil 
Table XIII. — Moisture conditions in subsoil of the various fields in IQI2 
Fallow. 
Grass field. 
Cornfield. 
Exposed subsoil. 
Hy¬ 
gro¬ 
scopic 
co¬ 
effi¬ 
cient. 
Ratio. 
J- 
M. 
Hy¬ 
gro¬ 
scopic 
co¬ 
effi¬ 
cient. 
Ratio. 
Hy¬ 
gro¬ 
scopic 
co¬ 
effi¬ 
cient. 
Ratio. 
Depth. 
June 
19. 
Aug. 
29. 
Hy¬ 
gro¬ 
scopic 
co¬ 
effi¬ 
cient. 
Ratio 
June 
19. 
Hy¬ 
gro¬ 
scopic 
co¬ 
effi¬ 
cient. 
Ratio 
Aug.- 
29. 
July 
9 - 
Aug. 
29. 
June 
19. 
July 
9 * 
Aug. 
29. 
Feel. 
3 . 
14.7 
1* 2 
1.8 
14-3 
r. 5 
* 4*3 
Z .2 
13-6 
z. 6 
1.4 
12.2 
a *4 
2.2 
2.2 
3 . 
* 3 * 5 
i. 6 
1.8 
13-6 
i -5 
13-6 
1.2 
13-7 
i -7 
1.4 
12.2 
2.4 
2.2 
2.2 
4 . 
13*0 
1.9 
1-7 
13*3 
1.6 
13-3 
1.2 
13-6 
1. 2 
i *5 
11.8 
2*5 
3*3 
2.4 
5 . 
13-0 
1.9 
1.8 
13-3 
1.9 
1 3-3 
1.2 
13 - 5 
i *7 
1.9 
12.0 
2. 6 
2.3 
2.4 
6... 
“13.0 
2.1 
2. 0 
13-2 
2.1 
13-2 
1.2 
13-3 
1.8 
2.0 
°I2.0 
2 . 7 
2.4 
a Datum missing. Value assumed. 
The fallow, grass field J, and exposed subsoil were sampled to a depth 
of 6 feet on June 19, using composites of three cores taken 10 to 15 feet 
apart with a soil tube. On July 9 the cornfield and exposed subsoil 
were sampled, and on August 29 the fallow, grassfield M, cornfield, and 
exposed subsoil. The data on the hygroscopic coefficients of only the 
samples taken on July 9 and those from the fallow on August 29 are 
available, the other samples through an oversight being thrown out 
before the determinations could be made. So, in order to compute the 
ratios, we have in the case of three fields, F, C, and S, used the single 
set of coefficients on each, and in that of field M the average of those 
for F and C. 
METHOD OF SAMPLING 
The samples were obtained by means of a 4-inch plate auger with a 
shield, made especially for the purpose. An iron tube of 4 inches inside 
diameter was driven 6 inches into the ground and the auger worked 
inside this. It carried an adjustable 6-inch shield which could be raised 
1 inch at a time and fastened by a setpin, thus automatically guarding 
against more than 1 inch of soil being removed without resetting the pin. 
The fields were sampled at two places, 10 to 20 feet apart, and the sam¬ 
ples from the duplicate sets combined. The soil from each of the twelve 
1-inch sections was placed in a covered can as soon as removed from the 
ground, thus preventing loss by evaporation between the time it was 
removed from the ground and its weighing. 
EXTREMES IN MOISTNESS 
The extremes in moistness were shown by the fallow and the grass- 
fields, the cornfield occupying an intermediate position, while the ex¬ 
posed subsoil with its lower water-retaining capacity in comparison with 
70393°—18 - 2 
