160 HOW CROPS FEED. 
if it is reduced to a very fine dust and duly watered, even 
the cereal grains will grow and perfect fruit on it. 
Magnus (Jour. fiir prakt. Chem., LL, '70) caused barley . 
to germinate in pure feldspar, which was in one exper:- 
ment coarsely, in another finely, pulverized. In the coarse 
feldspar the plants grew to a height of 15 inches, formed 
ears, and one of them ripened two perfectly formed seeds. 
In the fine feldspar the plants were very decidedly strong- 
er. One of them attained a height of 20 inches, and 
produced four seeds. 
It is true, as a general rulc, that a’l fertile soils contain 
a large proportion of fine or impalpable matter. The soil 
of the “Ree Ree Bottom,” on the Scioto River, Ohio, re- 
markable for its extraordinary fertility, which has remained 
nearly undiminished for 60 years, though yielding heavy 
crops of wheat and maize without interruption, is char- 
acterized by the fineness of its particles. (D. A. Wells, 
Am, Jour. Sci., XIV, 11.) In what way the extreme di- 
vision of the particles of the soil is connected with its fer- 
tility is not difficult to understand. The food of the plant 
as existing in the soil must pass into solution either in the 
moisture of the soil, or in the acid juices of the roots of 
plants. In either case the rapidity of its solution is in 
direct ratio to the extent of surface which it exposes. 
The finer the particles, the more abundantly will the p'ant 
be supplied with its necessary nourishment. In the Scioto 
valley soils, the water which surrounds the roots of the 
crops and the root-fibrils themselves come in contact with 
such an extent of surface that they are able to dissolve 
the soil-ingredients in as Jarge quantity and as rapidly as 
the crop requires. In coarse-grained soils this is not so 
likely to be the case. Soluble matters (manures) must be 
applied to them by the farmer, or his crops refuse to yield 
handsomely. 
It is furthermore obvious, that, other things being equal, 
the finer the,/ articles of the soil the more space the grow- 
