III. FOODS. By Edward Smith, M.D., LL.B., F. R. S. With numerous Illustrations. $1.75.

IV. MIND AND BODY: The Theories of their Relation. By Alexander Bain, LL. D. With Four Illustrations. $1.50.

V. THE STUDY OF SOCIOLOGY. By Herbert Spencer. $1.50.

VI. THE NEW CHEMISTRY. By Professor J. P. Cooke, of Harvard University. With 31 Illustrations. $2.00.

VII. ON THE CONSERVATION OF ENERGY. By Balfour Stewart, M. A., LL. D., F. R. S. With 14 Illustrations. $1.50.

VIII. ANIMAL LOCOMOTION; or, Walking, Swimming, and Flying. By J. B. Pettigrew, M. D., F. R. S., etc. With 130 Illustrations. $1.75.

IX. RESPONSIBILITY IN MENTAL DISEASE. By Henry Maudsley, M. D. $1.50.

X. THE SCIENCE OF LAW. By Professor Sheldon Amos. $1.75.

XI. ANIMAL MECHANISM: A Treatise on Terrestrial and Aërial Locomotion. By Professor E. J. Marey. With 117 Illustrations. $1.75.