338 HOW CROPS FEED. 
ments, 100 grms. of soil absorbed from 250 cubic centi- 
meters of solutions of chloride of potassium of various 
degrees of concentration, as follows: 
Strength of Solution. Potash absorbed by 
——— SS — eee =. ee ——— 
Designa- Quantity of potash in 250 ¢.c. 100 parts By 10,000 parts in Proportion 
tion. g of solution. of soil. round numbers. absorbed, 
1) 29 equiv. = 0.1472 gram. 0.9888 gram. 10 215 
1 40 a — 0.2944 ya 0.1381 Ke 14 1 lo 
ag ee his; = 0.5888 ‘ 0.1990 ‘ 20 1], 
ae = 5 Bes Ly 6g Ar al O:siet 31 1,4 
ole = = 2.3555 =* 0.4503“ 45 1), 
A glance at the right-hand column shows that although 
absolutely less potash is absorbed from a weak solution 
than from a strong one, yet the weak solutions yield 
relatively more than those which are concentrated. 
The quantity of base absorbed in a given time, also de- 
pends upon the relative mass of the solution and soil. In 
these experiments Peters treated a soil with various bulks 
of *|,, solution of chloride of potassium. The results are 
subjoined :— 
From 250 c.c. of solution 10,000 parts of soil absorbed 20 parts. 
6s 500 ce ia ae 6s ck 6e “ec ee 95 “e 
ae 1,000 ee ee ee ee “ce “ce “ec “e 99 ae 
The quantity of a substance absorbed by the soil de- 
pends somewhat on the state of combination it is in, 1. e., 
on the substances with which it is associated. Peters 
found, for example, that 10,000 parts of soil absorbed from 
solutions of a number of potash-salts, each containing 
‘|,. of an equivalent of that base expressed in grams, to 
the liter, the following quantities of potash :— 
From phosphate, 49 parts. 
“< hydrate, 40 “ 
4 “¢ carbonate, 5 
“ bicarbonate, rs aa 
“ . nitrate, ap. + 
“< sulphate, | Sp 
“¢  chloride* and carbonate,21 “ 
“chloride, rh i 
* Chloride of Potassium, KC}. : 
ee ee ee ee 
; ‘ ay 
— a a 
