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SCIENCE.— AD VER TISEMENTS. 



NEW CATALOGUE. 



We liave recently issued a new edition, revised and 

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Books on Chemistry, Chemical 

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It is arranged by subjects, and includes all the 

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A copy of this Catalogue will be sent free by mail 

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D. Van Nostrand Company, 



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23 Murray St. and 27 Warren St., New York. 

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Computation Rules 



and Logarithms. 



With Tables of other Useful Functions. By Silas 

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The Elements of Physics. 



A College Text-Book. By Edwakd L. Nichols, 

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 Vol. I. Mechanics and Heat. 8vo, cloth, $1.50 net. 



The Child and Childhood in 

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(The Child in Primitive Culture.) By Alexan- 

 der Francis Chaivibeelain, M.A., Ph.D., Lecturer 

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