_St. James's Gazette._--"The book may be safely recommended to those who desire to acquire an accurate knowledge of Geodesy." _Science Gossip._--"It is the best we could recommend to all geodetic students. It is full and clear, thoroughly accurate, and up to date in all matters of earth-measurements." THE PHYSICAL PROPERTIES OF GASES. By ARTHUR L. KIMBALL, of the Johns Hopkins University. Crown 8vo, cloth, Illustrated, _5s._ _Chemical News._--"The man of culture who wishes for a general and accurate acquaintance with the physical properties of gases, will find in Mr. Kimball's work just what he requires." HEAT AS A FORM OF ENERGY. By Professor R. H. THURSTON, of Cornell University. Crown 8vo, cloth, Illustrated, _5s._ _Manchester Examiner._--"Bears out the character of its predecessors for careful and correct statement and deduction under the light of the most recent discoveries." * * * * * LONDON: WILLIAM HEINEMANN, 21 BEDFORD STREET, W.C.