which
produces weight is co-extensive with the universe,--in short, to the
theory of universal gravitation and endless force. While learning how
to handle gases led to the discovery of oxygen, and to modern chemistry,
and to the notion of the indestructibility of matter.

Again, what simpler, or more absolutely practical, than the attempt to
keep the axle of a wheel from heating when the wheel turns round very
fast? How useful for carters and gig drivers to know something about
this; and how good were it, if any ingenious person would find out the
cause of such phenomena, and thence educe a general remedy for them.
Such an ingenious person was Count Rumford; and he and his successors
have landed us in the theory of the persistence, or indestructibility,
of force. And in the infinitely minute, as in the infinitely great,
the seekers after natural knowledge, of the kinds called physical and
chemical, have everywhere found a definite order and succession of
events which seem never to be infringed.

And how has it fared with "Physick" and Anatomy? Have the anatomist,
the physiologist, or the physician, whose business it has been to devote
themselves assiduously to that eminently practical and direct end,
the alleviation of the sufferings of mankind,--have they been able to
confine their vision more absolutely to the strictly useful? I fear they
are worst offenders of all. For if the astronomer has set before us the
infinite magnitude of space, and the practical eternity of the duration
of the universe; if the physical and chemical philosophers have
demonstrated the infinite minuteness of its constituent parts, and
the practical eternity of matter and of force; and if both have alike
proclaimed the universality of a definite and predicable order and
succession of events, the workers in biology have not only accepted all
these, but have added more startling theses of their own. For, as the
astronomers discover in the earth no centre of the universe, but an
eccentric speck, so the naturalists find man to be no centre of the
living world, but one amidst endless modifications of life; and as the
astronomer observes the mark of practically endless time set upon
the arrangements of the solar system so the student of life finds the
records of ancient forms of existence peopling the world for ages,
which, in relation to human experience, are infinite.

Furthermore, the physiologist finds life to be as dependent for its
manifesta