The International Scientific Series. (Continued.) 



19. ANIMAL PARASITES AND MESSMATES. By Professor P. J. VAN BEN- 

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 -30. FERMENTATION. By Professor P. SCHUTZENBERGER. With 28 Illustra- 

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2L THE FIVE SENSES OF MAN. By Professor JULIUS BERNSTEIN, Univer- 

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22. THE THEORY OF SOUND IN ITS RELATION TO MUSIC. By Pro- 

 fessor PIETRO BLASERNA, Royal University of Rome. With numerous 

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23 STUDIES IN SPECTRUM ANALYSIS. By J. NORMAN LOCKTER, F. R. S. 

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24. A HISTORY OF THE GROWTH OF THE STEAM-ENGINE. By Pro- 



fessor R. H. THURSTON, Cornell University. With 163 Illustrations, f 2.50. 



25. EDUCATION AS A SCIENCE. By ALEXANDER BAIN, LL. D. $1.75. 



26. STUDENTS' TEXT-BOOK OF COLOR ; or, Modern Chromatics. With 



Applications to Art and Industry. By Professor OGDEN N. ROOD, Colum- 

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27. THE HUMAN SPECIES. By Professor A. DE QUATREFAGES, Museum of 



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28. THE CRAYFISH : An Introduction to the Study of ZcOlogy. By T. H. 



HUXLEY, F. R. S. With 82 Illustrations. $1.75. 



29. THE ATOMIC THEORY. By Professor A. WURTZ. Translated by E. 



Cleminshaw, F. C. S. With Illustrative Chart. $1.50. 



80. ANIMAL LIFE AS AFFECTED BY THE NATURAL CONDITIONS OF 



EXISTENCE. By Professor KARL SEMPER, University of Wurzburg. 

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81. SIGHT : An Exposition of the Principles of Monocular and Binocular Vision. 



By Professor JOSEPH LE CONTE, LL. D., University of California. With 



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 85. GENERAL PHYSIOLOGY OF MUSCLES AND NERVES. By Professor 



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84. THE SUN. By Professor C. A. YOCTNG, College of New Jersey. With 83 



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85. VOLCANOES ; What they Are and What they Teach. By Professor JOHN 



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86. SUICIDE : An Eseay in Comparative Moral Statistics. By Professor HENRY 



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87. THE FORMATION OF VEGETABLE MOULD, THROUGH THE AC- 



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