DISTRIBUTION OF MOISTURE IN SOIL COLUMNS. 13 
Figure 4 shows graphically the data given in Table 5. The curves | 
_ for tubes Nos. 9 and 10 show that for the Whittier soil the maximum 
_ percentage of moisture is not at the bottom of the soil column, but 
at an appreciable distance above it. These curves show the same 
general form as the previous ones. Referring to the table, it will be 
seen that the maximum percentage of moisture in tube No. 9 is 
found at the fourth inch, or at one-seventh of the height. In tube 
No. 10 the maximum percentage of moisture is found at the fifth 
inch, or at one-fourth of the height. It is worth noting that the 
maximum percentage of moisture in these two tubes was found 
at about the same height, although the one tube stood 11 days longer 
than the other, and the moisture in tube No. 9 ascended nearly 50 
per cent farther than in tube No. 10. 
The average percentage of moisture found in tube No. 9 at the end 
of the experiment was 44.67 per cent, and in tube No. 10 the average 
percentage was 43.44 per cent. This is a very close agreement for 
two tubes so differently treated. This agreement would indicate 
that any different general arrangement of the moisture distribution 
that might occur in these columns with time would be very gradual, 
if it occurred at all. 
IntubeNo.9theaver- * 
age percentage of mois- 
ture is not found until 
about the sixteenth 
inch, or at a little less 
than two-thirds the 
height of the column. 
Intube No. 10 theaver- 
age percentage isfound 
at about the eleventh 
inch, or a little more 
than half the height. 
The curves for the Fig. 4.—Distribution et ee rou columns, Whittier 
Riverside soil, tubes a 
Nos. 11 and 12, show the same general moisture distribution as the 
preceding curves. The maximum percentage of moisture is found, 
not at the bottom inch, but at some distance above it. 
The curve for tube No. 11 shows rather a uniform distribution of 
moisture and only small secondary peaks. Although tube No. 12 
stood but a few minutes the maximum percentage of moisture is 
found above the third inch. The rather equal moisture distribution 
from the fourth to the sixteenth inch shown in tube No. 11 is note- 
worthy. 
Referring to Table 5, it is found that in Tube No. 11, the maximum 
percentage of moisture is 27.36, while the percentage of moisture in 
the first inch is only 23.55. The average percentage of moisture in 
tube No. 11 is 18.87, which is not found until the twenty-ninth inch 
or half-way up the tube. There is found in the bottom half of the 
tube 65 per cent of all the moisture in the tube, and but 35 per cent 
in the upper half of the tube. 
Tube No. 12 is inserted to show that the moisture distribution may 
follow the general rule, for tubes in water a few minutes only, as well 
as for those in water for a month or more. é 
ture 
& 
° 
19e,0f Mo/s 
Percenta: 
nN 
°o 
° 10 
0 30 
Inches Above Water 
