BULLETIN OF THE BUSSEY INSTITUTION. 355 
react upon lime when in presence of porous bodies may perhaps 
explain one class of cases in which salt has approved itself a useful 
manure. It is conceivable at all events that when salt is applied 
to soils of fit composition and contexture that contain carbonate of 
lime the above-mentioned reaction may occur, so that the land 
will really get a dressing of the soluble alkali (carbonate of soda) 
which is effective, as has been said, to promote the decay of humus, 
to bind the soil, and perhaps to disintegrate some useful mineral 
constituents of the soil. Indeed it is hardly possible to escape the 
conviction that there must be somewhere in the world soils whose 
fertility is promoted in this way; for we see in the alkali-deserts 
that the reaction between salt and lime does really occur in nature, 
the only trouble being that the reaction is commonly too strong for 
the purposes of agriculture — so much of the alkali being formed 
that vegetation, or at the least the texture of the soil, is destroyed 
by it. But since there is good reason to believe that small quan- 
tities of the alkali will conduce to fertility in certain cases, it is to 
be inferred that there must be some localities where the reaction oc- 
curs naturally in the proper degree. In saying this much I do not 
wish in the least to ignore the well-known fact that much harm 
may be done by saline fertilizers when they are put in improper 
places. Dr. Voelcker* has stated the matter well in connection 
with his experiments on the use of salt as a fertilizer. Writing for 
the climate of England he says: ‘‘ As far as my experience goes 
J am more and more constrained to look upon all very soluble sa- 
line manures as rather dangerous agents; for I have noticed over 
and over again the injury which these kinds of fertilizers produce 
in dry seasons, especially if they are applied rather late in spring. 
. . . Unless common salt or potash-salts can be applied to the 
land quite early in the spring I believe it would be better in nine 
seasons out of ten not to make any use of these very soluble mat- 
ters, which require to be thoroughly washed into the soil if they 
are to benefit the crops for which they are used.” 
In speaking of loams that had been wet with sea-water, or to 
which lime and chloride of potassium had been added, Mayer is 
inclined to attribute the observed compaction of the earth to the 
presence of chloride of calcium; and Reinders + dwells, in a some- 
what similar spirit, on the puddling of loams by sea-water. He 
speaks of an overflowed loam as being ‘‘ puddled, stiff, and out of 
* «¢ Journal of the Royal Agricultural Society,” 1870 (2), 6. 397. 
+ ‘Die landwirthschaftlichen Versuchs-Stationen,” 1876, 19. 201. 
