tallize together in all proportions." The precise quantity of
magnesia can only be determined by chemical analyses of the
stone.

There has been a long and wide-spread prejudice against the
use of this substance in agriculture; opinions adverse to its use
have been promulgated by ancient writers on the subject of agri-
culture; those have been taken up and adopted by others, without
examination, until, to urge the use of magnesian lime was a heresy
unheard of in the annals of agriculture. As long as men had opin-
ions not founded on reason and investigation, and so long as they
did not possess the means of investigation, they were entitled to
charity for their errors; but those who now commit them, can
give no such palliation for their commission. When the examina-
tion of the ashes of plants showed always a large per centage of
magnesia, common sense would seem to show that, inasmuch as
this magnesia could only be derived from the soil, that it should be
applied when wanting or deficient in the soil.

On the soils not containing a large quantity of vegetable matter,
from twenty to forty bushels of magnesian lime to the acre is the
best quantity. This quantity should be applied every three or four
years, until about two hundred bushels shall have been used. The
larger the per centage of magnesia in the lime, the smaller the
quantity to be used.

The proper quantity of lime per acre is a question, the solution
of which is attended with great difficulty. To arrive at as correct
conclusions as possible, I have examined very many productive
soils, and if their fertility depended solely on lime,—if it was the
only element to enter into the calculation, we might very readily
solve the question. But the fertility of a soil does not depend upon
the quantity, of any one constituent, but upon the proper proportion
of them, and also upon the mechanical texture of the soil. To ar-
rive at conclusions, then, we must not only have examined very
many different soils of known fertility, but also be cognizant of the
action of different quantities of lime upon soils of known compo-
sition.

The proper quantity, too, varies upon different soils, some re-
quiring a much larger quantity than others, whilst to many lands it
is entirely useless. The proper quantity depends—

1st. On the quantity of insoluble mineral matters in the soil.

2d. The quantity of undecomposed vegetable matter. The me-
chanical properties of the soil, when that is the only fault, can be
more cheaply improved by other means than lime.

Shell banks are another source from which lime is supplied to
soils in the tide-water counties of our State.

These shell banks are deposits of oyster shells made by the
aborigines of our country, and sometimes cover an area of forty
acres, in any places to the depth of six or eight feet.

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