Page:Popular Science Monthly Volume 21.djvu/574

This page has been proofread, but needs to be validated.

Extra Census Bulletins: Tables showing the Cereal Production of the United States by Counties, 1881, Pp. 36; Report on the Manufacture of Fire-Arms and Ammunition, by Charles H. Fitch, 1882, Pp. 36; Tables showing the Cotton Production of the United States by Counties, 1881, Pp. 5; Report on the Cotton Production of Louisiana, by Eugene W. Hilgard, 1881, Pp. 99. Washington: Government Printing-Office.

Report on Experiments and Investigations to develop a System of Submarine Mines. By Lieutenant-Colonel Henry L. Abbott. Washington: Government Printing-Office. 1881. Pp. 444.

Memoirs of the Science Department of the University of Tokio. No. 6, The Chemistry of Saki-Brewing, by R. W. Atkinson, B. So., Pp. 73; No. 7, Report on the Meteorology of Tokio for the Year 1880, Pp. 77, with Plates; and, The Wave-Lengths of some of the Principal Fraunhofer Lines of the Solar Spectrum, by T. C. Mendenhall. Ph.D., Pp. 27. Published by the university. Tokio, 1881.

Psychology of the Salem Witchcraft of 1692 By George M. Beard, M.D. New York: G. P. Putnam's Sons. 1882. Pp. 112. $1.

The Science of Ethics. By Leslie Stephen. New York: G. P. Putnam's Sons. 1882. Pp. 462. $4.

Antinous. A Romance of Ancient Rome. By George Taylor. From the German by Mary J. Safford. New York: William S. Gottsberger. 1882. Pp. 343. 75 cents.

Kant's Critique of Pure Reason. A Critical Exposition. By George S. Morris, Ph.D. Chicago: S. C. Griggs & Co. 1882. Pp. 272. $1.25.

Science Ladders. Edited by N. d'Anvers. No. 1. Forms of Land and Water, illustrated, Pp. 67; No. 3, Vegetable Life, illustrated, Pp. 78. New York: G. P. Putnam's Sons. 1882. 50 cents each.

Our Merchant Marine. By David A. Wells. New York: G. P. Putnam's Sons. Pp. 219. $1.25.

The Gospel of Law. By S. J Stewart. Boston: George H. Eilis. 1882. Pp. 326. $1 25.

A Geographical Reader. Compiled by James Johonnot. New York: D. Appleton & Co. 1882. $1.25.

Geological Sketches at Home and Abroad. By Archibald Geikie, LL.D., etc. With Illustrations. New York: Macmillan & Co. 1882. $1.75.

Physiognomy. A Practical and Scientific Treatise. By Mary Olmsted Stanton. Printed for the Author. San Francisco. 1831. Pp. 851.

What is Bright's Disease? Its Curability. Philadelphia: Published by the Author. 1882. Illustrated. Pp. 152. $1.

A Practical Treatise on Diseases of the Skin. By Louis A. Duhring. M.D. Third edition, revised and enlarged. Philadelphia: J. B. Lippincott & Co. 1.82. Pp. 685. $6.


The Great Telescope at Princeton.—The new telescope for the Halsted Observatory at Princeton has been mounted within the past few weeks, and is now ready for work. In magnitude it ranks at present as fourth among the great refracting telescopes of the world, and second in the United States. Its only superiors in size are the Vienna refractor, of twenty-seven inches diameter, the telescope of the Naval Observatory at Washington, twenty-six inches in diameter, and the telescope of Mr. Newhall, at Newcastle, in England, which has an aperture of twenty-five inches. A number of still larger instruments are indeed under construction, but it will be some time before any of them are actually in place. The object-glass of the Princeton telescope is twenty-three inches in diameter, and has a focal length of thirty feet. The glass disks were cast by Feil, in Paris, but the telescope was made by Alvan Clark & Sons, of Cambridge. Though the telescope is a little smaller than the Washington equatorial, its mounting is considerably heavier and firmer, and is improved in many respects. The regulator of the driving-clock is unusually-powerful, and, to prevent friction and wear of its pivots, its shaft is floated in mercury. The clamps and slow-motions are all managed without removing the eye from the eye-piece, and the declination circle is also read from the eye-end by a new and ingenious arrangement of the makers. The object-glass is peculiar in having its two lenses separated by a space of about seven inches, so as to allow a free circulation of air between them, thus greatly diminishing the disturbing effect of changes of temperature. This construction secures also freedom from the "ghosts" (formed by reflection between the lenses) which are so troublesome in many large instruments. The curves of the lenses are not those usually employed, but are somewhat like those of the Gaussian system, though not so deep. The color and spherical aberration are very perfectly corrected, and the performance of the glass, so far as can be judged from a few nights' work, is extremely fine. The instrument is, of course, provided with all the usual micrometers, eye-pieces, and other accessories, but as its chief occupation, for the present at least, is to be in the line of stellar spectroscopy, special attention has been given to the spectroscope, which is the most powerful ever made for star-work. It is a direct-vision instrument, on the plan of that used for some years back at Greenwich, though much larger. It was constructed by Hilger, of London, under the kind supervision of Mr. Christie (the present Astronomer Royal), in accordance with his own designs. It has