WORKS Of RICHARD ANTHONY PROCTOR. 



OTHER WORLDS THAN OURS: The Plurality of Worlds, studied 

 under the Light of Recent Scientific Researches. With Illustrations, 

 some colored. 12nio. Cloth. Price, $2.50. 



LIGHT SCIENCE FOR LEISURE HOURS. A Series of Familiar 

 Essays on Scientific Subjects, Natural Phenomena, etc. 1 vol., 

 12mo. Cloth. Price, $1.75. 



ESSAYS ON ASTRONOMY. A Series of Papers on Planets and Mete- 

 ors, the Sun, Stars, etc. With 10 Plates and 24 Wood Engravings. 

 1 vol., 8vo. Cloth. Price, $4.50. 



THE MOON : her Motions, Aspect, Scenery, and Physical Conditions. 

 With Three Lunar Photographs, and many Plates, Charts, etc. 1 

 vol., 8vo. Cloth. Price, $5.00. 



THE EXPANSE OF HEAVEN. A Series of Essays on the Wonders 

 of the Firmament. 1 vol., 12mo. Cloth. Price, $2.00. 



OUR PLACE AMONG 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. 

 1 vol., 12mo. Cloth. Price, $1.75. 



HELMHOLTZ (H.), Professor of Physics in the University of Berlin. 

 Popular Lectures on Scientific Subjects. Translated by E. Atkinson, 

 Ph.D., F. C. S. With an Introduction by Prof. Tyndall. 12mo. 

 Cloth. Price, $2.00. 



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