Soluble Constituents hi All u rial Soil. 



43 



The data are of value simply as showin<r the coaifrulating 

 action of slaked and quicklime, and to a less extent of bone 

 dust and gypsum upon the surface layers of clay soil, while all 

 the other manures appear to have either the opiX)site effect 

 or only a temporary coagulating action. There is, however, 

 no apparent relation between this action and the crop yield. In 

 addition the surface average falls distinctly after the winter 

 rains. 



The sandy soil proved to be more amenable to treatment, 

 and samples were taken from the plots, not only while the 

 crop was growing, but also in December, a month after it had 

 l)een harvested. The first sets of samples were taken practi- 

 cally sinmltaneously with the planting of the crop, and shortly 

 after manuring. The manui'es were applied in the same quan- 

 tity and order as in the clay plots. The sandy soil was of such 

 density that one acre 1 foot deep would weigh approximately 

 4,800,(100 lb., so that 18 inches deep would weigh 7,200,000 

 lb., and 2 inches deep, 800,000 lb. In the following table the 

 amount of manure applied per acre is given in the first column, 

 in the second column is the amount per kilogram in the super- 

 ficial 2 inches, as when first applied, and in the third column the 

 amount per kilogram when spread through the superficial 16 

 inches, assuming that none had been washed lower down. 



Manure 



Amount in 

 Amount ^iiperficial 



P-— Gnn?::;r 

 Kilotfi-ani. 



In Upper 



16 inches 



Plot 1 



Slaked Lime 



Nitrate of Soda 



Star Phosphate 



Gypsvim 



Bone Dust 



Ammonium Sulphate 



Blood Manure 



Superphosphate 



Quicklime 



Although the manures were, on the whole, applied in more 

 than the customary concentrations, the usual application of 

 star phosphate being, for instance, ^> cwt. per acre, it is evident 

 that by the time the manures are distributed through the upper 

 18 inches of soil the anuiunts per kilogram will be too small 



2 tons 

 1201b. 

 4c wt. 



1 ton 

 icwt. 

 8011.. 

 2cwt. 

 2cwt. 



2 tons 



5.(5 



0.148 



0.56 



2.8 



O.oG 



0.1 



0.28 



0.28 



5.6 



0.70 



0.016 



0.07 



0.35 



0.07 



0.012 



0.035 



0.035 



0.7 



