The eminence of Professor Young as an original investigator in astronomy, a lecturer and writer on the subject, and an instructor of college classes, and his scrupulous care in preparing this volume, led the publishers to present the work with the highest confidence; and this confidence has been fully justified by the event. More than one hundred colleges adopted the work within a year from its publication. _Young's Elements of Astronomy._ A Text-Book for use in High Schools and Academies. With a Uranography. By CHARLES A. YOUNG, Ph.D., LL.D., Professor of Astronomy in the College of New Jersey (Princeton), and author of _A General Astronomy_, _The Sun_, etc. 12mo. Half leather. x + 472 pages, and four star maps. Mailing Price, $1.55; for Introduction, $1.40; allowance for old book in exchange, 30 cents. _Uranography._ From Young's Elements of Astronomy. 12mo. Flexible covers. 42 pages, besides four star maps. By mail, 35 cents; for Introduction, 30 cents. This volume is a new work, and not a mere abridgment of the author's _General Astronomy_. Much of the material of the larger book has naturally been incorporated in this, and many of its illustrations are used; but everything has been worked over, with reference to the high school course. Special attention has been paid to making all statements correct and accurate _as far as they go_. Many of them are necessarily incomplete, on account of the elementary character of the work; but it is hoped that this incompleteness has never been allowed to become untruth, and that the pupil will not afterwards have to unlearn anything the book has taught him. In the text no mathematics higher than elementary algebra and geometry is introduced; in the foot-notes and in the Appendix an occasional trigonometric formula appears, for the benefit of the very considerable number of high school students who understand such expressions. This fact should be particularly noted, for it is a special aim of the book to teach astronomy scientifically without requiring more knowledge and skill in mathematics than can be expected of high school pupils. Many things of real, but secondary, importance have been treated of in fine print; and others which, while they certainly ought to be found within the covers of a high school text-book of astronomy, are not essential to the course, are relegated to the Appendix. A brief URANOGRAPHY is also presented, covering the constellations visible in the United States, with maps on a scale sufficient for the easy identification of all the principal stars. It includes also a list of such telescopic objects in each constellation as are easily found and lie within the power of a small telescope. _Plant Organization._ By R. HALSTED WARD, M.D., F.R.M.S., Professor of Botany in the Rensselaer Polytechnic Institute, Troy, N.Y. Quarto. 176 pages. Illustrated. Flexible boards. Mailing Price, 85 cents; for Introd., 75 cents.