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 At Bishop's Castle the swallows were noted to be gathering for departure ou the 10th, but many still remained on September 2nd.

At Alstonfield a great body of swifts {Hirunda apis) retired about the 10th. Hybernated specimen of the Painted Lady butterfly was seen on Derbyshire side on the 15th, and of Red Admiral on the 20th, The glow-worm was noted shining in the moist evenings after days of heavy rain. From Shifnal the Rev. J. Brooke writes—"Few butterflies, scarcely even white ones; and only one or two Red Admirals, Peacocks, and Tortoiseshells; not one Clouded Yellow, although we had such a strange Influx of this species in August, 1877. Swifts gone by the 10th."

We have already announced (p. 14l) the issue of the first part of the Proceedings of the Birmingham Philosophical Society, We now proceed to give same account of the contents, and in doing so warmly congratulate the Society on the goad work its members have already done. We trust this publication may prove to be the commencement of a long series of valuable contributions to local scientific literature. Of eighty-two pages of "Proceedings" seventy-five are covered by three papers.

The first of these is by the Rev. H. W. Watson, of Berkswell, and is on “The Kinetic Theory of Gases." Mr, Watson calls attention to the endeavours which have been made "to form a plausible theory of the constitution of a gas." He states, first of all, the theory in accordance with which the elasticity of a gas is the result of the mutual influences of the ultimate atoms of the gas upon one another. These atoms, it was supposed, mutually repelled one another, and the combined repulsion produced the outward thrust or pressure against the envelope of the gas. Mr. Watson points out how it can he demonstrated mathematically that such supposed mutual repulsion of the particles of a gas fails to account for the pressure which manifests itself, He then enters upon an explanation of the theory associated with the title of his paper. According ta this, the varying states of elasticity of gas imprisoned within any flexible and expansible envelope, of in any cylindrical chamber fitted with an air-tight movable piston, are due, not to the mutual repulsion of the gas particles, but to the varying energy with which they all vibrate across their points of mean position, The pressure upon the containing envelope always varies with the temperature of the gas; and as heat is now looked upon as a manifestation of energy of vibration. the adoption of “the kinetic theory of cases“ is but consistent with the reception already accorded to the corresponding theory #s to the nature of leat. Mr. Watson, however, very candidly shows that the kinetic theory, in one respect, fails to account for experimental results.