^•DTBXiic.A.a'ioisrs oe the 



JOHNS HOPKINS UNIVERSITY, 



I. American Journal of Mathematics. S. Newcomb, Editor, and T. Craig, 



Associate Editor. Quarterly. 4to. Volume XI in progress. $5 per 

 volume. 



II. American Chemical Journal. — I. Eemsbn, Editor. 8 Nos. yearly. 8vo. 



Volume XI in progress. $4 per volume. 

 HI. American Journal of Philology. — B. L. G-ildersleeve, Editor. Quar- 

 terly. 8vo. Volume IX in progress. $3 per volume. 



IV. Studies from the Biological Laboratory. — Including the Chesapeake 



Zoological Laboratory. H. N. Martin, Editor, and W. K. Brooks, Asso- 

 ciate Editor. 8vo. Volume IV in progress. $5 per volume. 



V. Studies in Historical and Political Science. — H. B. Adams, Editor. 



Monthly. 8vo. Volume VII iD progress. $3 per volume. 



VI. Johns Hopkins University Circulars. — Containing reports of scientific 



and literary work in progress in Baltimore. 4to. Vol. VIII in progress. 

 $1 per year. 



VII. Annual Report.— Presented by the President to the Board of Trustees 

 reviewing the operations of the University during the past academic year. 



VH. Annual Register. — Giving the list of officers and students, and stating 

 the regulations, etc., of the University. Published at the close of the Aca- 

 demic year. 



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Manufacturers of Balances and Weights of Precision for Chem- 

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AMERICAN JOURNAL OF SCIENCE. 



Founded by Professor Silliman in 1818. 



Devoted to Chemistry, Physics, Geology, Physical Geography, Mineralogy, 

 Natural History, Astronomy, and Meteorology. 



Editors: James D. Dana and Edward S. Dana. 



Associate Editors: J. P. Cooke, Jr., George L. Good ale, and John Trow- 

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Two volumes of 480 pages each, published annually in MONTHLY NUMBERS. 



This Journal ended its first series of 50 volumes as a quarterly in 1845, and its 

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 menced in 1871. 



Twenty copies of each original communication are, if requested, struck off for 

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