NATURAL SCIENCE. 99 



Young's Elements of Astronomy. 



A Text-Book for use in High Schools and Academies. With a Uranog- 

 raphy. 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 Sitn, etc. 12mo. Half leather, x + 472 pages, and 

 four star maps. Mailing Price, $1.55; for Introduction, $1.40; allow- 

 ance 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. 



HHHIS 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 il- 

 lustrations 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 incom- 

 plete, 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 constella- 

 tions 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. 



