Unlike but mutually-adapted physical growth and expenditure, including the functions of reproduction, are held to balance and equalize the physical well-being of the sexes. It is further claimed that their psychical powers, dependent upon and working through adapted organisms, are also thereby maintained in a perpetually-adjusted equilibrium. The hypothesis assumes true mental equivalence, which is secured through inherent, varying, constitutional provisions.
My sole claim to originality must lie in the attempt to briefly and insufficiently indicate how Nature has wrought to achieve a continuous and progressive balance of the sexes from the beginning until now. It remains to complete the work; to determine how much of one set of characters is the mathematical equivalent of counterbalancing quantities.
Extremely accurate and detailed estimates are doubtless out of the question. The simplest computations are so inexact that even the mean distance of the earth from the sun still awaits revision. However, "in time," science must be able to offer sufficiently accurate, incontrovertible proof that men and women are, or are not, intellectually peers.
A. B. Blackwell.
Somerville, N. J., March, 1876.
THE "NEW PHILOSOPHY" OF HEAT.
To the Editor of The Popular Science Monthly.
In opening a copy of Bailey's Dictionary, published in London in 1775, my eye fell upon the following: "Heat (according to the New Philosophy) very much consists in the rapidity of motion in the smaller parts of bodies, and that every way; or in the parts being rapidly agitated all ways. Its operation upon the senses we call Heat, and is estimated according to its relation to the organs of feeling, which motion of its small parts must be brisk enough to increase or surpass that of the parts of the sentient, for if it be more weak or languid, it is said to be cold."
I was under the impression that the theory concerning heat which involves this definition is of modern development. What is the truth on the subject?
E. R. Craven.
The doctrine which makes heat consist in molecular motion, or in an agitation of the minuter parts of which material things are constituted, is old as a speculation, but modern as a scientific demonstration. Locke said, more than a hundred years ago, "Heat is a very brisk agitation of the insensible parts of an object, which produces in us that sensation from which we denominate the object hot, so that what in our sensations is heat, in the object is nothing but motion." Similar views may be vaguely traced in the writings of Galileo, Bacon, Newton, Leibnitz, Descartes, Bernoulli, and Laplace. But they were unverified conjectures, and could not take their place among the principles of science until experimentally proved. This was first done by Count Rumford, in his celebrated experiments at the Munich Arsenal, and published in the "Proceedings of the Royal Society for 1798." But Rumford's results were ignored for half a century. Dr. Whewell published the history of thermotics in 1837, without mentioning him. He was far in advance of his age, both in his philosophical views regarding heat and the experimental evidence by which he sustained them. When, from 1840 to 1850, various physicists and chemists entered upon lines of research that led to the general doctrine of the convertibility or correlation of forces, the labors of Rumford began to be appreciated, and the truth concerning the nature of heat being proved in various ways, became accepted in science and part of a "new philosophy," in a sense quite different from that in which these terms were used in the last century.
