sept. 9,1918 Variations in Moisture Content of a Loess Soil 
457 
kept well mixed, we might use even a single value for the first 6 sections, 
as we do in Table V. Even in the old grass field J and in the exposed 
subsoil the hygroscopicity does not vary widely from inch to inch of the 
lower half of the foot section. 
The soils involved in this study are well represented by the Lincoln 
surface soil D and subsoil A, which we have used in various laboratory 
studies involving the movement of water (2, p. 32; 3, p. 399 ), the former 
being taken from various parts of the 10-acre field F-C and the latter 
from an adjacent excavation. 
The variation in density from field to field is, as we have previously 
pointed out (1, p . 224), so great as to make data on the apparent specific 
gravity desirable. In June, 1912, we took from each of the fields two 
sets of composite samples, each from five borings, using the 4-inch plate 
auger mentioned below. Considerable variations in density (Table III) 
are shown, but scarcely sufficient to necessitate the use of different values 
in computing from the moisture percentages the equivalent in inches 
of rain. While the exposed subsoil was the most dense of all, the espe¬ 
cially high values found for the surface inch of this are to be attributed 
to the beating effect of the rains. In the bluegrass pasture there was 
i no distinct variation from level to level, except that the first inch was 
much the least dense. The surface layer of 6 or 7 inches in the corn¬ 
field was distinctly lighter than the lower portion of the foot section. 
Table III .—Apparent specific gravity of the soil at the different levels 
Bluegrass pasture. 
Cornfield. 
Exposed subsoil. 
Depth. 
Set I. 
Set II. 
Aver¬ 
age. 
Set I. 
Set II. 
Aver¬ 
age. 
Set I. 
Set II. 
Aver¬ 
age. 
Inches. 
O. 87 
O. 81 
O. 84 
i-35 
I. 20 
I. 28 
x. 63 
I. 94 
I. 81 
I. 17 
I. 19 
I. 18 
1. 09 
I. 07 
I. 08 
I. 42 
I. 38 
I. 40 
3 . 
I. 23 
I. 29 
I. 26 
i -13 
I. 16 
I. 15 
x*35 
I. 38 
i *37 
4 . 
I. 22 
I. 28 
1-25 
1. 18 
I. 02 
I. IO 
i* 33 
I. 44 
1. 41 
5 . 
I. l6 
I.25 
I. 21 
i- 
I. 03 
I. 10 
1. 49 
1. 56 
1. 52 
I. l6 
I. 21 
I. 19 
1. 09 
I. II 
I. 10 
1.32 
1* 5 1 
1. 42 
7 . 
I. IO 
I. 20 
I. l6 
1. 11 
I. IO 
I. II 
1. 42 
1. 48 
i*45 
8 . 
I. l6 
I. 24 
I. 20 
1.14 
I. 29 
I. 22 
1. 40 
1* 52 
i*45 
9 . 
I. 19 
I. 21 
I. 20 
1. 27 
I. 32 
I. 29 
i*37 
i*37 
i*37 
10. 
I. 21 
I, 22 
I. 22 
1.32 
i*35 
1* 33 
1. 32 
I * 39 
1.36 
11. 
I. 24 
1-25 
I. 24 
1* 33 
i* 34 
i* 34 
i*37 
i*35 
1. 46 
12 .: 
I. 24 
1*25 
I. 24 
1. 36 
1-34 
i*35 
1*25 
1.42 
x. 34 
Average. . . .I 
1 
I. l6 
I. 20 
I. l8 
1. 20 
1. 20 
1. 20 
1. 40 
1. 48 
1.44 
CONDITIONS DURING AN EXTREME SPRING DROUTH 
WEATHER OP 1910 
A striking feature of the weather of 1910 at Lincoln was the record- 
breaking drouth of the spring. The autumn of 1909 had been unusually 
wet (Table IV) and favorable for the moistening of the soil, while in 
