of the pole when there was
any thing to climb after, and an Admiralty expedition could do no more.

_Poisoning of Vegetables_.

Several very curious experiments on the poisoning of vegetables, have
recently been made by M. Marcet, of Geneva.--His experiments on arsenic,
which is well known to every one as a deadly poison to animals, were
thus conducted. A vessel containing two or three bean plants, each of
five or six leaves, was watered with two ounces of water, containing
twelve grains of oxide of arsenic in solution. At the end of from
twenty-four to thirty-six hours, the plants had faded, the leaves
drooped, and had even begun to turn yellow; the roots remained fresh,
and appeared to be living. Attempts to restore the plants after twelve
or eighteen hours, by abundant watering, failed to recover them. The
leaves and stem of the dead plant gave, upon chemical examination,
traces of arsenic. A branch of a rose-tree, including a flower, was
gathered just as the rose began to blow; the stem was put into a vessel,
containing a solution of six grains of oxide of arsenic in an ounce of
water. The flower and leaves soon showed symptoms of disease, and on the
fifth day the whole branch was withered and dead, though only one-fifth
of a grain of arsenic had been absorbed. Similar stems, placed in pure
water, had, after five days, the roses fully expanded, and the leaves
fresh and green.

On June 1st, a slit of one inch and a half in length was made in the
stem of a lilac tree, the branch being about an inch in diameter. The
slit extended to the pith. Fifteen or twenty grains of moistened arsenic
were introduced, the cut was closed, and the stem retained in its
original position by osier ties. On the 8th, the leaves began to roll up
at the extremity; on the 28th, the branches were dry, and, in the second
week of July, the whole of the stem was dry, and the tree itself dead.
In about fifteen days after the first, a tree, which joined the former a
little above the earth, shared the same fate, in consequence of its
connexion with that into which the poison had been introduced. Other
trees similarly cut, but without having been poisoned, suffered no kind
of injury.

M. Marcet's experiments upon vegetable poisons are no less interesting,
and still more wonderful, as indicating a degree of irritability in
plants somewhat similar to that which depends on the nervous system in
animals. After having ascertained that the bean plants