POLARISATION OF LIGHT. By W. Spottiswoode, F.R.S. With Illustrations. Fourth Edition. Crown 8vo. 3s. 6d.

THE SCIENCE OF WEIGHING AND MEASURING, AND THE STANDARDS OF MEASURE AND WEIGHT. By H. W. Chisholm, Warden of the Standards. With numerous Illustrations. Crown 8vo. 4s. 6d.

HOW TO DRAW A STRAIGHT LINE: a Lecture on Linkages. By A. B. Kempe. With Illustrations. Crown 8vo. 1s. 6d.

LIGHT: A Series of Simple, Entertaining, and Inexpensive Experiments in the Phenomena of Light, for the Use of Students of every age. By A. M. Mayer and C. Barnard. With numerous Illustrations. Crown 8vo. 2s. 6d.

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SEEING AND THINKING. By Professor W. K. Clifford, F.R.S. With Diagrams. Crown 8vo. 3s. 6d.

DEGENERATION. By Professor E. Ray Lankester, F.R.S. With Illustrations. Crown 8vo. 2s. 6d.

FASHION IN DEFORMITY, as Illustrated in the Customs of Barbarous and Civilized Races. By Professor Flower. With Illustrations. Crown 8vo. 2s. 6d.

CHARLES DARWIN. Memorial Notices reprinted from Nature. By Thomas Henry Huxley, F.R.S.; G. J. Romanes, F.R.S.; Archibald Geikie, F.R.S.; and W. T. Thiselton Dyer, F.R.S. With a Portrait engraved by C. H. Jeens. Crown 8vo. 2s. 6d.

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