‘In all the nineteen chapters into which the work is divided there is much both to interest and to instruct the general reader, while deserving the attention of the “dietetic reformer.” . . . The author has made almost a life-long study of the subject.’—ENGLISH MECHANIC. _OTHER WORKS BY MR. MATTIEU WILLIAMS._ Crown 8vo. cloth extra, 7_s._ 6_d._ SCIENCE IN SHORT CHAPTERS. ‘Few writers on popular science know better how to steer a middle course between the Scylla of technical abstruseness and the Charybdis of empty frivolity than Mr. Mattieu Williams. He writes for intelligent people who are not technically scientific, and he expects them to understand what he tells them when he has explained it to them in his perfectly lucid fashion without any of the embellishments, in very doubtful taste, which usually pass for popularisation. The papers are not mere réchauffés of common knowledge. Almost all of them are marked by original thought, and many of them contain demonstrations or aperçus of considerable scientific value.’—PALL MALL GAZETTE. ‘There are few writers on the subjects which Mr. Williams selects whose fertility and originality are equal to his own. We read all he has to say with pleasure, and very rarely without profit.’—SCIENCE GOSSIP. ‘Mr. Mattieu Williams is undoubtedly able to present scientific subjects to the popular mind with much clearness and force: and these essays may be read with advantage by those, who, without having had special training, are yet sufficiently intelligent to take interest in the movement of events in the scientific world.’—ACADEMY. Crown 8vo. cloth limp, 2_s._ 6_d._ A SIMPLE TREATISE ON HEAT. ‘This is an unpretending little work, put forth for the purpose of expounding, in simple style, the phenomena and laws of heat. No strength is vainly spent in endeavouring to present a mathematical view of the subject. The Author passes over the ordinary range of matter to be found in most elementary treatises on heat, and enlarges upon the applications of the principles of his science—a subject which is naturally attractive to the uninitiated. Mr. Williams’s object has been well carried out, and his little book may be recommended to those who care to study this interesting branch of physics.’—POPULAR SCIENCE REVIEW. ‘We can recommend this treatise as equally exact in the information it imparts, and pleasant in the mode of imparting it. It is neither dry nor technical, but suited in all respects to the use of intelligent learners.’—TABLET. ‘Decidedly a success. The language is as simple as possible, consistently with scientific soundness, and the copiousness of illustration with which Mr. Williams’s pages abound, derived from domestic life and from the commonest operations of nature, will commend this book to the ordinary reader as well as to the young student of science.’—ACADEMY. London : CHATTO & WINDUS, Piccadilly, W. Demy 8vo. cloth extra, price 7_s._ 6_d._ THE FUEL OF THE SUN.