Page:Popular Science Monthly Volume 32.djvu/876

854 library of every American consul, and the purchase of a sufficient number of copies to supply those officers would be a very proper transaction on the part of the State Department.

of the "Century" magazine will give this handsome volume a cordial welcome without the formality of an introduction, for the chapters of which it is composed have appeared from time to time as illustrated articles in that periodical. Those who are not already acquainted with the fascinating style in which the author depicts the wonders of modern astronomy will derive even more pleasure from the book. In explanation of his title, "The New Astronomy," Professor Langley says that until very lately the prime object of astronomy has been "to say where any heavenly body is, and not what it is," but that, within a comparatively few years, a new branch of the science has arisen, "which studies sun, moon, and stars for what they are in themselves and in relation to ourselves." This branch of astronomy, sometimes called celestial physics, deals with the constitution, condition, and configuration of the sun, moon, and planets; of meteors, comets, and stars. The view of this field which Professor Langley gives is general rather than detailed, for his book is not addressed to the professional reader, but is intended to solicit for the "new" astronomy the interest and support of the educated public. It is admirably adapted to produce this effect. Its descriptions are picturesque without bending the lines of fact, and its language is vivid without being inaccurate. Ninety-three figures, many of them of full-page size, embellish the volume, and the paper, printing, and design of the cover are of the handsomest. Four of the eight chapters of the work are devoted to the sun. The author takes up first the spots on the sun, those immense blotches sometimes exceeding in extent the whole surface of our globe, and tells what is known as to their cause. He regards as not proved the idea that sun-spots have an influence on the weather, thereby affecting harvests on the earth, but a connection between the spots and terrestrial magnetic disturbances he deems sufficiently established. The sun's corona, as seen in eclipses, and the solar prominences are next described. In the two chapters on the sun's energy some idea of the quantity of heat radiated from the sun is given, and the question of how the solar fire is fed is discussed. The absolute dependence of all activity and life on earth upon the supply of heat received from the sun is pointed out, and the idea of a greater need for utilizing this heat in the future by means of solar engines is suggested. Of the planets, Saturn, Jupiter, and Mars are selected for special attention. The moon is described with gratifying fullness, and an excellent idea of its surface is given by the reproductions of lunar photographs, and of photographs of volcanic formations on the earth, and of other wrinkled and cracked surfaces, which are inserted for comparison. The phenomena of meteors and comets are presented in the same enthusiastic style which characterizes the rest of the book. The concluding chapter embodies some of the results of the application of the spectroscope to stellar research. The volume is an admirable one for the library of the cultured general reader, for it gives information without an array of figures which are as wearying to everybody but specialists as they are interesting to that class; it presents conceptions of the vast magnitudes, distances, and forces of the visible universe in the form in which they can be best grasped; and while it inspires a respect for the great results which have been accomplished by the genius and industry of modern astronomers, it also conveys a sense of the boundless regions of space beyond the range of their instruments, for the present unknown to earthly intelligence, and, perhaps, forever unknowable.

above-named edition of Professor Proctor's "Half-Hours" appears with maps and text specially prepared for American students. It is an atlas of twelve maps, showing the position of the principal star groups throughout the year, with an explanation of each map, and an introduction.