y matter. And out of these same forms of
ordinary matter, and from none which are simpler, the vegetable world
builds up all the protoplasm which keeps the animal world a-going.
Plants are the accumulators of the power which animals distribute and
disperse.

But it will be observed, that the existence of the matter of life
depends on the pre-existence of certain compounds; namely, carbonic
acid, water, and certain nitrogenous bodies. Withdraw any one of these
three from the world, and all vital phaenomena come to an end. They are
as necessary to the protoplasm of the plant, as the protoplasm of the
plant is to that of the animal. Carbon, hydrogen, oxygen, and nitrogen
are all lifeless bodies. Of these, carbon and oxygen unite in certain
proportions and under certain conditions, to give rise to carbonic acid;
hydrogen and oxygen produce water; nitrogen and other elements give rise
to nitrogenous salts. These new compounds, like the elementary bodies
of which they are composed, are lifeless. But when they are brought
together, under certain conditions, they give rise to the still more
complex body, protoplasm, and this protoplasm exhibits the phaenomena of
life.

I see no break in this series of steps in molecular complication, and I
am unable to understand why the language which is applicable to any one
term of the series may not be used to any of the others. We think fit to
call different kinds of matter carbon, oxygen, hydrogen, and nitrogen,
and to speak of the various powers and activities of these substances as
the properties of the matter of which they are composed.

When hydrogen and oxygen are mixed in a certain proportion, and an
electric spark is passed through them, they disappear, and a quantity
of water, equal in weight to the sum of their weights, appears in their
place. There is not the slightest parity between the passive and active
powers of the water and those of the oxygen and hydrogen which
have given rise to it. At 32 degrees Fahrenheit, and far below that
temperature, oxygen and hydrogen are elastic gaseous bodies, whose
particles tend to rush away from one another with great force. Water, at
the same temperature, is a strong though brittle solid whose particles
tend to cohere into definite geometrical shapes, and sometimes build up
frosty imitations of the most complex forms of vegetable foliage.

Nevertheless we call these, and many other strange phaenomena, the
properties of the water, and we