Relation of Xonauailablc Water to Hygroscopic Coefficient 51 
Table 9 gives a summary of the initial moisture conditions 
in the different cylinders, of the crops grown, and of the dates of 
harvesting the crops and opening the cylinders. 
CYLINDERS WITHOUT PLANTS. 
These were left undisturbed from the time that they were 
placed in the greenhouse until they were removed from the pit 
and opened, except from time to time to examine them by means 
of a spatula for the formation of a crevice along the cylinder 
wall and to test them by means of a sharp pointed stick, for the 
presence of a crust under the surface mulch. Xo crevice formed 
and no hard crust was found, altho when the cylinders were 
opened on May 13 a crust was beginning to form in each. 
As shown in Table 10, the percentage of total moisture in- 
creased steadily from the surface to the bottom of the first foot, 
where there was a sudden drop from 22 per cent to 13 per cent. 
From this point on down it increased steadily to the bottom of 
the subsoil, where it reached 21 per cent. There was practically 
the same moisture content at corresponding depths in the two 
cylinders. The surface foot was much drier than in the experi- 
ment in 1900 and much less water had been lost by evaporation. 
0 5 10 15 20 25 30 Jl 
Moisture Content in PcrCent 
Fig. 7. Final moisture conditions in ten cylinders with the moistest sur- 
face soil. 
