1856.] Science and the Bible. 637
operated on, etc.; and so finds, as another lesson, a definite and
simple relation between chemical constitution and the boiling points of
compounds, — a profounder law.
we note the amount of heat absorbed when substances pass from a liquid
state to that of a vapor, or from a solid to a liquid ; find the amount
1000 deg. F. in the former case, and 142 deg. in the latter, and
observe that this heat absorbed (or given out in the reverse changes)
does not vary the temperature of the substances undergoing the change.
In this way we ascertain another law of heat, called the law of latent heat.
We observe again, making our measurements with extreme care, that different substances expand unequally with
the same addition of heat; and, therefore, that there are specific
differences between substances. In this way we read off what is called
the specific heat of those substances, and, by comparing,
arrive at its general law. The chemical philosopher, with this law and
its details in mind, observes that there is a close relation between
these specific heats and the combining weights of elements, so exact
that one is directly deducible from the other. Thus he opens a new
chapter in the chemistry of nature ; or, rather, nature throws a flood
of new light into his mind.
searching out the constitution of matter, he simply divides the
compound into its constituents, by processes carefully studied, and
then weighs those constituents, having balances that will weigh to
thousandths of a grain. By weighing in one case after another, and
setting down the amounts, he reads, again, a grand truth, that the
elements and their compounds have definite combining weights. Then,
pursuing it farther, the law of simple ratios, in the combinations of
each element, is deciphered.
investigation of nature is thus carried on by applying our weights and
measures, as much so as in measuring a piece of cloth or weighing a
pound of lead ; and the generalizations, called laws, are the results
of comparisons among these measurements. The mind rises, through
natural induction, from specific to comprehensive truths.