Crystals

Transcriber’s Note:
The cover image was created by the transcriber and is placed in the public domain.
International Scientific Series
VOLUME XCVIII.
DIRECT REPRODUCTIONS OF AUTOCHROME PHOTOGRAPHS OF SCREEN PICTURES IN POLARISED LIGHT.
Fig. 90.—Screen Picture in Polarised Light, with Nicols crossed, of a thick Plate perpendicular to the Axis of a naturally twinned Crystal of Quartz, the left half being of right-handed Quartz and the right half of alternately left and right-handed Quartz, the Planes of Demarcation being oblique to the Plate.
Fig. 97.—Crystals of Benzoic Acid in the Act of Growth, as seen on the Screen in Polarised Light with crossed Nicols.
The International Scientific Series
A. E. H. TUTTON
D.Sc., M.A. (New College, Oxon.), F.R.S.
VICE-PRESIDENT OF THE MINERALOGICAL SOCIETY MEMBER OF THE COUNCILS OF THE CHEMICAL SOCIETY AND THE BRITISH ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE
WITH 120 ILLUSTRATIONS