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the above title a series of five articles recently appeared in "The Popular Science Monthly," describing the aspect of the starry heavens as seen through that most available variety of the telescope—the opera-glass. These descriptions included directions for recognizing the constellations and the principal stars, and were illustrated with numerous star-maps and views of the sun and moon, while many allusions to the history and mythology of the subject added to the interest of the text. The articles called forth many lively expressions of pleasure, both from the newspaper press and from individual correspondents, which is not surprising, for the "Monthly" has seldom if ever published a series of papers whose scientific accuracy and fascinating style made them more deserving of the name of popular science than these. The series, rearranged and enlarged, is now published in book form. The volume contains an introduction, composed of matter recast from the articles in the "Monthly," devoted to telling what a good opera-glass is. This is followed by four chapters, devoted respectively to the stars of spring, summer, autumn, and winter, and a chapter on "The Moon, the Planets, and the Sun," the accounts of the planets being new. Throughout the work, and in some parts on almost every page, new matter has been introduced, intended to make the subject clearer and more interesting to the reader, and to render the book enjoyable and useful reading to those who may not care to follow out, opera-glass in hand, the directions and descriptions contained in it. Accounts of additional stars, star-groups, and other objects have been inserted, also fresh references to star-lore, as well as to advances in our knowledge of the heavens made since the series appeared in the magazine. The radiant points of some of the principal meteor-showers have been indicated; also the places in the heavens of the points known as the solstices and equinoxes. Additional descriptions have also been introduced of the revolution of the heavens and its effect upon the places of the constellations at different seasons and different hours. New matter has been added on the history of the Pleiades; about Sirius and Procyon, and their strange companion-stars; and about star-clusters. All the illustrations of the article on "The Stars of Spring" were redrawn and re-engraved for the book, and several new ones have been added in this chapter and in that on "The Moon, the Planets, and the Sun." The volume is printed in large, clear type, on fine paper, and is bound in a notably tasteful and appropriate style.

work is described by the translator as containing all that is necessary for an accurate and complete determination of the rock-making minerals. In the first part of the volume the optical properties of minerals are described, with some account of their morphological characters, their phenomena of cohesion and chemical properties. In the second or descriptive part the minerals treated are arranged according to their system of crystallization, being divided into two groups, isotropic and anisotropic minerals. The former group comprises amorphous substances and those belonging to the isometric system; the latter group is subdivided into minerals with one optic axis (tetragonal and hexagonal systems), and those with two optic axes (orthorhombic, monoclinic, and triclinic systems). There are, besides these, a few crypto-crystalline substances, which are placed under the head of aggregates. Each section in the first part, and each species in the second, is preceded by a list of the literature of the subject. Twenty-six plates of photo-micrographs and one hundred and twenty-one woodcuts illustrate the text.

aim of this work is to aid improvement in a department where improvement has been sadly needed. School-houses have been like barns in the country, and like warehouses in the city, rather than fit places for children to exist and study in. The book