H. P. Armsby— Absorption of Bases by the Soil. 25 
Art. III.—On the absorption of Bases by the Soil; by H. P. 
ARMSBY. 
THE question of the nature of the absorptive power of the 
soil for bases may be regarded as still to a certain extent an 
open one. Although the researches of Henneberg & Stoh- 
mann, Peters, Weinhold and others have shown concluslvely that 
the absorption is accompanied by a chemical reaction between the 
salt whose base is absorbed and the soil, an equivalent quan- 
tity of other bases being dissolved ; and though the investiga- 
tions of Way, Hichhorn, \Rantenberg, Heiden, Knop and 
Mulder have as conclusivel; connected this reaction with the 
presence in the soil of certain zeolitic silicates which appear to 
be the agents of absorption; it has been the opinion of many 
distinguished authorities, e. g., Liebig, Brustlein, Henneberg 
& Stohmann, that the prime cause of absorption is physical 
Im its nature. 
The fact which more than any other has served to sustain 
this view is the peculiar effect of the concentration and volume 
of the solution upon the amount of absorption. As is well 
other porous bodies. Peters and others hold that the physical 
force is the prime cause, and that the chemical phenomena are 
only secondary, while others believe that chemical action is the 
Prime cause and is modified by physical force. Knop ad- 
which can unite with the acid, and that then the chemical 
union of the base follows. 3 
Pillitz (Fres, Zeit., xiv, 55 and 282) has indeed found that, if 
a large volume of solution be filtered through a soil until no 
removed, since in his experiments the absorption was constant. 
But these facts, however interesting and important, neither 
