A System of Mineralogy: Descriptive Mineralogy comprising the most Recent Discoveries

Abstract

II. EXCEPT in the subdivisions of the silicates, Professor Dana has adhered pretty nearly to the classification adopted in his fourth edition; which accords also in its general features, though not in its details, with that on which the minerals in the British Museum are arranged. The arrangement of the silicates in his new edition is a step that must be called tentative towards a simpler and more philosophical classification of these numerous and important salts. We certainly feel some hesitation in adopting either the terminology or the divisions Professor Dana introduces. The terms bi- and uni-silicate are not happy for the expression of oxygen ratios; not so happy, for instance, as the term singulo-silicate used for the latter by Rammelsberg, or the ortho-silicates of Odling. We own to a partiality for the view of Dr. Odling regarding the different classes of silicates, on the ground partly of the harmonious relations he introduces between these and other multibasic salts, and also from the satisfactory way in which these very important minerals group themselves as ortho-, para-, or meta-silicates. We may take another occasion for illustrating this, and pass on to Professor Dana's new and scholarlike handling of the whole question of nomenclature. A System of Mineralogy: Descriptive Mineralogy comprising the most Recent Discoveries. By James Dwight Dana, Silliman Professor of Geology and Mineralogy in Yale College, etc., aided by George Jarvis Brush, Professor of Mineralogy and Metallurgy in the Sheffield Scientific School of Yale College. Fifth edition, 8vo. pp. 827, figures 617. (London: (Trubner & Co.)