﻿BECKER BROTHERS, 



No, 6 Murray Street, New York, 



Manufacturers of Balances and Weights of Precision for Chem- 

 ists, Assayers, Jewelers, Druggists, and in general for every use 

 where accuracy is required. 

 April, 1871.— [tf.] 



MINERALOGY AND GEOLOGY. 



PROFESSORS and COLLECTORS interested in the above Sciences and 

 VISITORS to LONDON are invited to inspect SAMUEL HENSON'S 

 Collection of MINERALS, ROCKS, GEMS and PRECIOUS STONES. 



BLOWPIPE CASES AND APPARATUS. 

 Catalogue on application. 



SAMUEL HENSON, 



277 STRAND, LONDON, Opposite Norfolk Street, 

 July, 6t. 



PUBLICiLTIOISrS OIE 1 TJE3IE 



JOHNS HOPKINS UNIVERSITY. 



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



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

 volume. 



II. American Chemical Journal. — I. Remsen, Editor. Bi-monthly. 8vo. 



Volume VIII in progress. $3 per volume. 



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



terly. 8vo. Volume VII 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 III in progress. $5 per volume. 



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



Monthly. 8vo. Volume IV in progress. $3 per volume. 



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



and literary work in progress in Baltimore. 4to. Vol. V in progress. $1 

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

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



VIE. 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. 



Communications in respect to exchanges and remittances may be 

 sent to the Johns Hopkins University (Publication Agency), Baltimore, 

 Maryland. 



MUSPRATTS CHEMISTRY. 



FOURTH GERMAN EDITION. 



By Stohmann & Kerl and many other chemists, now publishing in 7 volumes, 

 4°, by subscription, in fortnightly parts, at 40 cents, duty paid. If desired, the 

 parts can be mailed from our Leipzig house, direct, at 32 cents; duty, if any, to 

 be paid by addressee. Scientific Catalogue on application. 



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