16 
Effect on soil No. 673. — This soil, of all the types examined, pos- 
sessed the greatest capillary activity and was least affected by the 
addition of salts. In fact, it may be assumed that the capillary 
activity of this soil is unaffected by the addition of outside agents as 
the results agree with the check within the limits of experimental 
error. In view of the above facts, a series of experiments was car- 
ried out in which the amount of salt added was doubled, the results 
[of which agreed very closely with those reported above. 
Effect on soils Nos. 516 and 5Jf2. — These soils are of very similar 
mechanical composition but belong to different chemical types. The 
data presented indicate that the clay tends to dominate the capillary 
activity of this type of soil in that the addition of aU substances 
diminished capillarity. 
Effect on soil No. 630. — The physical character of this type of soil 
is such that chemical agents would be expected to materially affect 
its texture. This theory is borne out in the diminished capillary 
activity noted in every instance. 
Effect on Icaolin. — The diminished capillarity observed in the study 
of the effect of salts on kaolin shows a direct relationship between 
this substance and clay soils. 
Any attempt at classification of the above results according to 
theoretic considerations only indicates the complexity of applying 
any one theory to soils. More than one factor evidently enters into 
play to which it is necessary to give due consideration. That fer- 
tilizers do markedly affect capillarity is clearly shown. In using 
mixed fertilizers there is little variation in rise as related to variation 
in mixture. Those in which nitrates are used show decrease in water 
rise as compared with those containing ammonium sulphate. 
EFFECT OF BASICITY ON CAPILLARITY. 
Organic manures, as compared with the salts, retard the rise in the 
sandy soils and decrease the rise in others. As a rule, magnesium 
salts affect capillarity less than the calcium salts, potassium salts less 
than ammonium, sodium less than potassium, and the monobasic 
salts in most instances less than the dibasic. Among the monobasic 
salts, carbonates and phosphates show the lowest, sulphates next, 
nitrates next, and chlorids the highest water line. 
With the phosphates the rise of moisture seems to depend upon the 
acidity or basicity of the salt. This may be observed by comparing 
data in Table VII with those in Table VI under the phosphates of 
lime. Here also the relation between acidity and rise of moisture is 
similar to that observed in the case of the potash salt. 
