during hibernation by sucking his paws; but it may not be so generally known that the waste thus induced in the anterior extremities is restored by the moral consciousness of the animal that the fat he is so carefully hoarding is to confer a posthumous blessing on mankind.  This is a touching example of the adaptation of means to end, and Shakspeare, the great natural philosopher, has made use of it for one of his most striking metaphors, where he says, “that the thought of something after death must give us paws.”]

“6.  Discoursing on the elasticity of the air, the writer styles it ’the most compressible of bodies,’—­as if it had any advantage in this respect over the numerous other species of gaseous matter.  As to the illustration which he gives, namely, that ’a glass vessel full of air, placed under a receiver and then exhausted by the air-pump, will burst into atoms,’ we can only say, what every schoolboy knows, that the bursting would be inwards, unless, indeed, our meteorologist means that the external receiver was to be exhausted, and in that case he should so have expressed himself.”

[The theory of exhausted receivers is, in our opinion, worthy only of the childhood of science, when chemistry and astronomy were alchemy and astrology, and people would believe anything.  In this enlightened age of the universal subscription-paper, exhausted givers are familiar objects, but a receiver who finds the labors of his calling excessive is as non-existent as the harpy, his mythological prototype.]

“7.  In regard to the extent to which the compression of air has been actually carried, he tells us that ’Brockhaus says that air has as yet been compressed only into one-eighth of its original bulk.’  Is it possible that a writer on Meteorology is unacquainted with the well-known experiments of Dulong and Arago, and the more recent ones of Regnault, in which the compression was three times the amount here stated, or that he requires to be referred to those of Natterer, who, by a powerful condensing apparatus, has lately compressed seven hundred and twenty-six volumes of air into a single volume?”

[Any man who has succeeded in condensing seven hundred and twenty-six volumes into one deserves the applause of the reading public.  We trust M. Natterer will extend his benevolent labors to all the great libraries.  With the most perfect apparatus of compression, however, we doubt if contemporary literature will yield anything like so high an average as 1 in 726.]

“8.  In the paragraphs devoted to the optical relations of the atmosphere, our author has shown a happy faculty for making his subject obscure.  After suggesting that the refraction of the rays in the atmosphere may be due to what he calls its ‘lenticular outline,’ he defines refraction to be ’the bending of a ray passing obliquely from a rarer into a denser medium,’—­a good enough popular definition, but for its sad defectiveness.  Is