SCIENCE.— AD VER TISEMENTS. 



Dec. 1,1896. Just Published. Sixth Edition of 



THE MICROSCOPE ^S^L^^^T^.l'bT- 



By SIMON HENRY QAQE, Prolessor of Microscopy, His- 

 tology and Embryology in Cornell University and the 

 New York State Veterinary College, Ithaca, N. Y., U.S A. 

 Sixth edition, rewritten, greatly enlarged, and Illustrated 

 by 165 figures in the text. Price, $1.50, postpaid. 



COMSTOCK PUBLISHING CO., Ithaca, N. Y, 



Now READY. 



Light, Visible and Invisible. 



By SILVANUS P. THOMPSON, D.Se., 



F.B.S., M.M.L, Principal of, and Professor of Physics in, 



the City and^Guild's Technical College^ 



Finsbury, London. 



With Numerous Illustrations. 

 12mo. Cloth, pp. xii + 294. Price $1.50. 



CONTENTS OF THE VOLUME: 



Light and Shadows. 



The Visible Spectrum and the Eye. 



Polarization of Light. 



The Invisible Spectrum (ultra-violet part). 



The Invisible Spectrum (infra-red part). 



Eontgen Light. 



This volume brings up to date the late discoveries and 

 theories, and it will be found invaluable both to the student 

 and to the general reader. The subject is treated in a sim- 

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THE mmm company, SS Fifth Ave,. New York. 



NEW CATALOGUE. 



We have recently issued a new edition, revised and en- 

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HOUGH'S "AMERICAN WOODS" 



A publication illustrated by actual specimens. 



WOODS FOR THE STEREOPTICON 



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Fhjsical Gbical, Microscopical i Electrical ipparatus 



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