in the ground,
exercising a chemical action upon the soil which extends to any depth of
it; and that, in consequence of the chemical and mechanical
modifications of the earth, particles of certain nutritive elements
become accessible and available to plants that were not so before.

It is said plaster is of most benefit in wet seasons; such is not
always the case. It is certainly beneficial to clover, wet or dry; so of
potatoes.

A few years since, when the drought was so intense in this section as to
render the general potato crop almost a total failure, the writer
produced a plentiful crop by the use of plaster alone. On examination at
the dryest time, the bottoms of the hills were found to be literally
dust, yet in this dust the tubers were swelling finely: the leaves and
vines were of a deep rich green, and remained so until frost, while
other fields in sight, planted with the same variety, but not treated
with plaster, were brown, dead, and not worth digging. That gypsum
attracts moisture may be proved by plastering a hill of corn and leaving
a hill by it unplastered; the dew will be found deposited in greater
abundance on the plastered hill. But, according to Liebig, certain
products of the chemical action of plaster enter into and are
incorporated with the structure of the plant, closing its breathing
pores to such an extent that the plant is enabled to withstand a drought
which would prove fatal to it unassisted.

Certain it is that plaster renders plants less palatable to insects,
and, so far as the writer's experiments extend, it is fatal to many of
the fungi family. To obtain the best results, the vines of potatoes
should be dusted with plaster as soon as they are fairly through the
soil, again immediately after the last plowing and hoeing, and, for
reasons hereafter given, at intervals throughout the whole growing
season. The first application may be light, the second heavier, and
thereafter it should be bountifully applied, say two hundred pounds per
acre at one sowing.

THE POTATO-ROT--ITS CAUSE

The year 1845 will ever be memorable by its giving birth to a disease
which threatened the entire destruction of the potato crop, and which
caused suffering and pecuniary ruin to an incredible extent throughout
Europe.

The potato, at the time of the appearance of the potato disease, was
almost the sole dependence of the common people of Ireland for food.
That over-populated country experienced more actu