NATURE 



[August 24, 1905 



MR. EDWARD ARNOLD'S NEW BOOKS. 



THE EVOLUTION THEORY. 



By AUGUST WEISMANN, 



Professor of Zoology in Ihe University of Freiburg. 



TRANSLATED BY 



Professor J. ARTHUR THOMSON and MARGARET THOMSON. 



Two volumes, Royal 8vo. With many Illustrations. 32s.net. 



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AN INTRODUCTION TO 



THE THEORY OF OPTICS. 



By ARTHUR SCHUSTER, Ph.D., Sc.D., F.R.S., 



Professor of Physics at the University of Manchester. Demy 8vo. 

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T/Mi:S.~" We have in Dr. Schustei's book a notable addition to the 

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THE CHEMICAL SYNTHESIS 

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And the Inter-Relations between Organic Compounds. 

 By R. MELDOLA, F.R.S., V.P.C.S., F.I.C., &c., 



Professor of Chemisiry in the City and Guilds of London Technical College, 

 Finsljjry. Super Royal Svo. 21s.net. 



THE BECQUEREL RAYS 



AND THE PROPERTIES OF RADIUM. 



By the Hon. R. J. STRUTT, 



Fellow of Trinity College, Cambridge. Demy Svo. With Diagrams. 

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London: EDWARD ARNOLD,*! & 43 Maddox St., W. 



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MIT 198 ABBILDUNGEN I M TEXT UND AUF 12 TAFELN. 



GK. S". 1905. 



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