for certain special ends; but, as we have seen, the whole vegetable
kingdom uses the eight or ten primitive elements which it has in common
with the animals, and out of these alone forms the infinite variety of
products which we derive from it for food and various economical
and aesthetical purposes. Among the many processes of Nature whose
contemplation fills us with ever new delight, this power of the
adaptation of a few means to an infinite number of ends is one of the
most enchanting. We endeavor to explain by chemical laws the reduction
of the materials which earth and air furnish, to a form in which they
can be appropriated by the tree; by endosmose and exosmose we think we
have overcome the obstacles to a clear comprehension of the circulation
of the sap; and by a cell-theory we believe we have explained the whole
growth of wood and leaves and fruit. But what microscope or what alembic
shall ever tell us why a collection of tubes and cells in one tree
creates the most wholesome and delicious fruit, while in another an
organization precisely similar, so far as we can discern, produces only
harsh and poisonous berries? why the acacia tribe elaborate their gum,
the pine family turpentine, the almond prussic acid, the sorrels oxalic
acid? why the tall calisaya-tree of the Andes deposits in its bark the
valuable medicine cinchona, and the oak, the hemlock, the tea-plant, and
many others, make use of similar repositories to lay up stores of
tannic acid? The numberless combinations of the same materials, and
the wonderful power which rests in a single seed to bring about with
unvarying uniformity its own distinct result, attest to us every day the
admirable wisdom and goodness of the Creator.

These regular, every-day transformations of material elements from rock
to tree, from tree to man, and back through a continual circuit, would
repay us for spending our leisure hours in studying it, with our own
eyes as well as with the eyes of others. The glance we have given is