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Popular Science Monthly/Volume 9/July 1876/Correspondence

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CORRESPONDENCE.

THE WATER-HAMMER.

To the Editor of the Popular Science Monthly.

SIR: The following phenomenon can, perhaps, be explained by yourself or one of your readers: I have a water-hammer, made of a straight tube of glass, about eighteen inches long and three-quarters of an inch in diameter. At the top of the tube there are two bulbs, the upper one about half the size of the lower, with only a narrow passage of about a sixteenth of an inch in width to connect the lower bulb with the tube, and the upper bulb with the lower.

About one-third of the tube contains water. When the tube is inverted, and the water allowed to fill both bulbs, it will not, upon the tube being reversed, run out, but will remain in the bulbs for an indefinite time, until shaken or otherwise disturbed. This may be owing to adhesion simply, or, possibly, to capillary attraction, but it is not to this fact chiefly that I wish to call your attention. The water being in the bulbs, and the tube held with the bulbs upward, if a smart blow with the palm of the had be applied at the bottom of the tube, there arises, under certain conditions which I have been unable to determine, a ringing noise resembling sometimes the singing of a bird, sometimes the noise produced by a thin iron instrument—a fork, for instance—when knocked rapidly against an empty tumbler. During this time, no water escapes from the bulbs, but the water at the mouth of the lower bulb is violently agitated, as if small particles of air were quickly ascending to the height of a quarter of an inch in the bulb. Not a drop of water is displaced, the water remaining at the bottom of the tube not being perceptibly increased while the noise continues. It lasts sometimes from five to ten minutes, and it seems as though, under favorable conditions, it might continue indefinitely. Very frequently, however, the experiment does not succeed, though apparently all the conditions are exactly the same. Here, therefore, are two questions:

1. What is the reason why the water, when caused to enter the bulbs, does not flow out of them when the position of the tube is reversed, but remains stationary as if there was no such thing as gravity, and, in this case, a vacuum besides?

2. What is the reason of the singing noise above described?G. M.

New York, March 23, 1876.


To the Editor of the Popular Science Monthly.

Will you allow me to state the precise ground of objection to your criticism of my book, "The Sexes throughout Nature?" "What she proposes to do," you affirm, "is nothing less than to reduce the whole organic world, with all its vital and physical characters, into exact and demonstrable quantitative expression."

I only insist that, until science can offer us exact quantitative proof that the total of male characters is in excess of the total of female characters, no scientist should assume to determine, on scientific authority, that woman is inferior to man. I make no attempt to place my hypothesis, that, in each species of being, the sexes are true equivalents, on a "demonstrable quantitative" basis.

Though presented in the form of equations, and defended in a series of carefully argued propositions, the theory waits to be tested experimentally and quantitatively. It assumes to be nothing but a provisional hypothesis, destined to be either confirmed or rejected, as it is found to agree or not to agree with the decisive facts of Nature. I merely offer various evidence in defense of the assumption that, physical powers compared with physical, and psychical powers with psychical, the female is everywhere the equal of the male of its own species.

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.