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formed me that they have experienced most excellent effects from
it when used in this way, many of which I have witnessed.—
There is another valuable effect of this lime not possessed by
any other, which is its tendency to destroy insects.

I have been informed of many applications of gas lime, always
with beneficial effects when applied properly. The supply of it in
our market does not more than meet the demand.

Shell Marl is another most fruitful source for the application of
lime to soils, and moreover a most valuable one. In my previ-
ous Reports to the House of Delegates, I have spoken very fully
of its best mode of application, the quantity to be used and in-
deed every thing of practical value connected with it The an-
alyses of many marls not published in my Reports have been
given to the interested, to the whole people of the State, I
omit their republication. For much of my advice I have been
indebted to information given personally by, and from the prin-
ted publications of the Hon. Edmund Ruffin, of Va., whose works
on the subject of Calcareous Manures, especially marl, contain
more valuable original truths than any one, or all written on
these subjects. Persons living in the tide water districts of our
country, will find them to be most valuable sources of information.

Miscellaneous Manures.

Gypsum—Common Salt.—We comprise these two manures un-
der one head; not that they are similar either in their composi-
tion or mode of action, but because there is no very appropriate
class to which they can be referred; and they act more as mediums
than as direct nutriments.

Gypsum in its pure state is composed as follows :

Lime............................................. 33 per cent.

Sulphuric acid................................. 46 ''

Water........................................... 21 "

Experience has determined that the crops on which it should
be used are those only which have a large leafy surface, such as
clover, beans, peas cabbage and tobacco, and is best applied to
clover, peas, beans, cabbage and tobacco when their leaves first
begin to expand; on corn it should be used just when the silk
begins to form. On wheat, timothy, oats, &c, its beneficial ac-
tion is not so clearly manifest as on the crops which I first men-
tioned.

Very much has been said with regard to the theory, i. e., the

philosophical explanation of the way, or ways, in which plaster

acts. On this subject I can but say that the beneficial influence

of plaster on broad leaf plants must be explained in some other

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