6 SCIENCE AND PHILOSOPHY. 



Hours of Exercise in the Alps. By Prof. JOHN TYNDALL. With Illustra 

 tions. 1 21110. Cloth, $2.00. 



Faraday as a Discoverer. A Memoir. By Prof. JOHN TYNDALL. 12mo. 



Cloth, $1.00. 



Fragments of Science for Unscientific People. A Series of Detached 

 Essays, Lectures, and Reviews. By Prof. JOHN TYNDALL. lie-vised and en 

 larged edition. 12mo. Cloth, $2.50.&quot; 



Address delivered before the British Association, assembled at 



Belfast. By Prof. JOHN TYNDALL. Revised, with Additions, by the Author, 

 since the Delivery. 12mo. Paper, 50 cents. 



Essays on the Floating- Matter of the Air, in Relation to Pu 

 trefaction and Infection. By Prof. JOHN TYNDALL. With Illustrations. 

 12mo. Cloth, $1.50. 



Ressarchfts on Biamagmetism and Magn^-Crystallic Action. In 

 cluding the Question of I Hamagnetic Polarity. By Prof. JOHN TYNDALL. With 

 10 Plates. 12mo. Cloth, $1.50. 



Louis Pasteur: His Life and Labors. By his SON-IN-LAW. Translated from 

 the French by LADY CLAUD HAMILTON. With an Introduction by Prof. JOHN 

 TYNDALL. 12mo. Cloth, $1.25. 



WORKS OF PROFESSOR R. A. PROCTOR. 



The Moon: Her Motions, Aspect, Scenery, and Physical Condition*, with Two 

 Lunar Photographs, and many Illustrations. By R. A. PKOCTOU. New edition. 

 12ino. Cloth, 13.50. 



The Expanse of Heaven. A Scries of E*KIVS on the Wonders of the Firma 

 ment. By R. A. PEOCTOR. 12mo. Cloth, $2.&amp;lt;;6. 



Ligrht Science for Leisure Hours. Familiar Essays on Scientific Subjects, 

 Natural Phenomena, etc. By R. A. PROCTOR. 12mo. Cloth, $1.75. 



Other Worlds than Ours: The Plurality of Worlds, studied under the Lipht 

 of Recent Scientific Researches. By E. A . PROCTOR. With Illustrations, some 

 colored. 12mo. Cloth, $2.50. 



Our Place amonsr Infinities. A Series of Essays contrasting our Little 

 Abode in Space and Time with the Infinities around us. To which are added 

 Essays on the Jewish Sabbath and Astrology. By R. A. PROCTOR. 12mo. 

 Cloth, $1.75. 



ASTRONOMY. 



Elements of Astronomy. By ROBERT STO-WKTL BALL. T,L. P., F.R.S., 



Andrews Professor of Astronomy in the University of Dublin, Roval Astronomer 

 of Ireland. With Illustrations. 10mo. Cloth, $2.25. 



Origin of the Stars, and the Causes of their Motion and their 

 Lig-ht. By JACOB ENNIS. 12mo. Cloth. $2.00. 



Elements of Astronomy; accompanied with numerous IllustraMons. a Colored 

 Representation of the Solar, Stellar, and Nebular Spectra, and Arapo s Celestial 

 Charts of the Northern and the Southern Hemispheres. By J. NORMAN LOCK- 

 YER. Fellow of the Royal Astronomical Society. Editor of &quot;Nature.&quot; etc. Ameri 

 can edition, revised and specially adapted to the Schools of the United States. 

 12mo. Cloth, $1.50. 



Astronomy with an Opera-Glass. A Popular Introduction to the Study 

 of the Starry Heavens with the Simplest of Optical Instruments. With Map s 

 and Directions to facilitate the Recognition of the Constellations and the Principal 

 Stars visible to the Naked Eye. By Q A BRETT P. SKRVI-B. (Svo. Cloth, $1.50. 



Outlines of Astronomy. By Sir J. J. W. HKRSCHEL. With Plates and 

 Woodcuts. Eleventh editiou. Svo. Cloth, $4.00. 



