Relation of Nonavailable Water to Hygroscopic Coefficient 61 
Cylinder with 7 per cent free water in the subsoil. — 
Cylinder XIX was filled like XIII and XIV, except that moist 
subsoil containing 13.0 per cent total water — 7.4 per cent free 
water — was used. All the plants did well until near the end of 
March, the four plants having 8 tillers on March 28. About the 
middle of April two of the plants began to die and were dead by 
June 11. The other two continued to develop until they had put 
three spikes part way out of the sheath. By June 8 they had 
ceased to grow but were still alive when June 12 arrived. The 
one spike bore three shrunken grains, while the other two bore 
none. The moisture conditions in both the surface foot and the 
subsoil were like those in XIII — with negative free moisture 
( — 4.3 per cent) in the former and practically none (0.2 per cent) 
in the latter. The subsoil was uniformly dry at the different 
depths. There was a fair development of roots to the very bot- 
tom of the subsoil. In this cylinder also the plants perished 
independently of one another. 
Cylinder with 12 per cent free water in the subsoil. — 
Cylinder XX differed from XIX in that it was filled with moist 
soil containing 11.5 per cent free water. All four plants in this 
did well until the end of April when the four plants had 11 tillers 
in all. One plant began to die. but the other three continued to 
grow. They all wilted on May 17 but recovered and put forth 4 
spikes which were not yet ripe on June 11. The high tempera- 
ture of the following day killed all the plants. The earliest spike 
bore 6 shrunken grains. The surface foot contained — 3.8 per 
cent free water and the subsoil an average of 1.5 per cent, it being 
quite uniformly distributed. Roots occurred thruout the sub- 
soil, but in the lower foot sections thev were much less numerous 
than in XTX. 
Two cylinders with moister soil near the surface. — Cylin- 
ders V and VI were filled with air-dry subsoil and surface soil 
and then to the surface was added the amount of water required 
to make the total weight of water in the cylinders equal to 18 
per cent of the weight of the dry subsoil plus 25 per cent of that 
of the dry surface soil. The total amount of moisture in V and 
VI was almost the same as that in XX — 8.076 and 8.007 grams 
against 8.060 grams — but the distribution of this thruout the soil 
mass was quite different. 
The plants in V and VI made the most vigorous growth of all. 
On March 26 the plants in both cylinders suffered some slight 
injury from mice. On April 27 the 4 plants in the former had 
19 tillers and those in the latter had 20. On that date there 
were removed from VI three plants having 11 tillers, thus leaving 
