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132 lowering the water to the Provo level. A chapter is devoted to the lake sediments found within the Bonneville shore-line, after which a connected history of the Bonneville basin is given, and a parallel is drawn between this and the history of Lake Lahontan. The relation of volcanic eruption to the lake history is treated separately, as is also the effect of movements of the earth's crust in deforming the shore-lines. The volume ends with a discussion of the Equus fauna, which is not found within the limits of Lake Bonneville, but which is connected with the lacustrine history introduced into an earlier chapter. There is an appendix on Altitudes and their Determination, by Albert L. Webster, and two on geodetic problems connected with the ancient lake, by R. S. Woodward. The volume is liberally illustrated with full-page, double-page, and many smaller views, maps, diagrams, etc., many of the maps being colored, and there is a folded map of the lake, about three feet by two, which is also printed in colors.

importance is given in this book to the American colonies, in which British colonization began, and which are the most extensive; and they are historically, statistically, and comparatively presented in tables and diagrams. A distinction is drawn between the North American and the West Indian colonies, while the Bermudas and the Falkland Islands lie outside of both. The North American colonies, though they include islands, are continental; while the West Indian, though they extend to the continent, are, on the whole, a collection of island dependencies. In Canada and Newfoundland the drawbacks to colonization have been ice and snow; in the West Indies they have been tropical heat and hurricanes. In the Northern colonies nearly all the inhabitants are of European origin; in the West Indies blacks predominate. There are other historical as well as racial distinctions, but one point the two groups have in common: "They are settlements, and not mere dependencies. The heat of the West Indies has not prevented the British race from colonizing the islands, and, though the negro race has long been greatly superior in numbers to the white, the history of an island like Barbados shows that even in the tropics the connection between Great Britain and America has been that of permanent settlement rather than of passing trade or foreign rule." The Bermudas, the West Indian colonies, those of the South American coast, the Falkland Islands, and South Georgia are described, historically and geographically, and the descriptions are illustrated by good though small maps.

The relative merits of the incandescent electrical light and some other lights that are suggested are discussed by Prof. E. L. Nichols, of Cornell University, on The Artificial Light of the Future. The author finds that there are limitations to the life and usefulness of the incandescent light and of the arc light that are not likely to be overcome. Inquiring for a better light, he finds that of magnesium superior in quality and efficiency to any other as yet known. It affords, weight for weight, thirty times the light obtained from gas, with the development of much less heat, and gives the nearest approach to sunlight in whiteness; while in illuminating power each unit of it must be regarded as the equivalent of rather more than 1·25 units of gaslight. It has a quality believed to be the same as that named by Prof. Wiedemann luminescence, an effect, akin to phosphorescence, fluorescence, etc., of a different class of molecular vibrations from those which cause incandescence, to which importance is attached, enabling it to radiate light without heat. A similar quality belongs to the oxide of zinc, the properties of which as an illuminating substance are also studied.

From ''Wm. Paul Gerhard,'' consulting engineer for sanitary works, three monograph pamphlets are received, the nature and value of which are indicated by their titles. They are Architecture and Sanitation, in which the advantages of employing a sanitary engineer for building-work related to his sphere are insisted upon; Notes on Gaslighting and Gas-fitting, which abounds in practical suggestions; and the Disposal of Sewage of Isolated Country Houses, a matter