e Cabbage tribe considered wholesome food?

Because their acrid flavour is dipersed among an abundance of
mucilage. Cabbages were commonly used among the ancients, and Cato
wrote volumes on their nature. The Indians had so much veneration for
them, that they swore by cabbages, and were therein as superstitious
as the Egyptians, who gave divine honours to leeks and onions, for the
great benefits which they said they received from them.--_Lemery on
Food._

Why do Cabbages emit a strong animal odour?

Because they contain a great quantity of azote or nitrogen, one of the
ultimate elements of animal matter, and strongly characterized in the
destructive distillation of horn, hoofs, or bones.

Why do not the leaves of the Cabbage remain wet, after being immersed
in water, and again taken out of it?

Because they are powdered with a slight layer of resinous matter,
similar to that which covers certain fruits, and, in particular, plums
and grapes. Their sea-green colour is also attributed to this resinous
layer.

Why is Quassia so called? Because it was named in honour of a negro,
Quassia, a drunken doctor, who discovered the virtue of the wood in
curing malignant fevers.

Why is the Ice plant so called?

Because its stem is covered with soft tubercles, or excrescences,
which have a crystalline appearance.

Why do the leaves of some trees fall very early?

Because they are articulated to the branch; that is, they do not unite
with it by the whole of their base, but are simply fixed to it by
a kind of contraction or articulation; as in the maple and horse
chestnut.

Why do leaves fall at the approach of winter?

Because a separation takes place, either in the foot-stalk, or more
usually at its base, and the dying part quits the vigorous one, which
is promoted by the weight of the leaf itself, or the action of the
gales that blow in autumn on its expanded form. M. Richard explains
the cause more philosophically: "Although the fall of the leaves
generally takes place at the approach of winter, cold is not to be
considered as the principal cause of this phenomenon. It is much more
natural to attribute it to the cessation of vegetation, and the want
of nourishment which the leaves experience at that season, when the
course of the sap is interrupted. The vessels of the leaf contract,
dry up, and soon after, that organ is detached from the twig on which
it had been developed."

Why do some trees, as the Oak, the Beec