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The Editors beg to return tlieir thanks to their respective Corre- 

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They have also to acknowledge the receipt of the following, to which 

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Mr. Graham on the Finite Extent of the Atmosphere. 



Dr. Reads on the Nature of Light and Shadow. 



Mr. Haworth on New Succulent Plants. 



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PHARMACOFCEIA londinensis, 



Iterum recognita et retractata, 1824', p. 6. 

 "ACIDUM ACETICUM FORTIUS," 

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THENARD'S TREATISE ON CHEMICAL ANALYSIS, trans- 

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SCIENTIFIC LIBRARY, for the Use of Schools, Private Students, 

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This Day is published, price 4j. 6d. 



A SYSTEM OF POPULAR GEOMETRY, containing in a few 

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London : Published for John Taylor, by James Duncan, 37, Pater- 

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