B % WESTERMANN & CO., 



(Established 1848.) 



838 Broadway . . . NEW YORK, 



FOREIGN BOOKSELLERS AND IMPORTERS. 

 QUSTAV E. STECHERT, 



766 Broadway, New York. 



Importer of Scientific Books and Periodicals. 

 Branches : Leipzig, Hospital Str. 16 ; London, 26 

 King William Str., Strand. 



PHOTO -MICROGRAPHY. 



GAYTON A. DOUGLASS & CO. 



Merchants in all supplies pertaining to 

 Photography. 



Catalogues furnished on application. 

 Correspondence solicited. 



185 & 187 Wabash Ave., Chicago. 

 SAMUEL HENSON, 



Mineralogist and Geologist, 



invites visitors to London to inspect his choice speci- 

 mens of Minerals, Gems, and Polished Stones. 

 Catalogue on application. 



SAMUEL HENSON, 277 Strand, London, 



OPPOSITE NORFOLK STREET. 



SCIENCE 



1 



"THE ELECTRICAL REVIEW," 



An illustrated weekly journal, is theacknowledged lead- 

 er in the world of electrical science. Edited with cart, 

 it* editorial opinion is reliable, its news columns bright 

 and instructive. $3.00 per year ; single copies, 10 cents. 

 23 PARK EOW, NEW YORK. 

 Best advertising medium in the electrical field. 



I 



MAGAZINES AND REVIEWS!! 



Complete sets of all the leading Magazines and Reviews and 

 back numbers of several thousand periodicals, for sale at low 

 rates. Full files of Science, either bound or unbound, or odd 

 volumes and numbers supplied. Subscriptions taken on favorable 

 terms for any periodical either American or foreign. Address 

 THE AMERICAN AND FOREIGN MAGAZINE DEPOT, 

 47 Dey street, Kew York City. 



GERMAN SIMPLIFIED. 



An eminently practical new method for learning the German lan- 

 guage. Edition fcr self-instruction, in 12 numbers, at 10 cents each, 

 sold separately ; school edition (without keys), bound in cloth. $1.25. 

 For sale by all booksellers ; sent post-paid on receipt of price by Prof- 

 A. KNOFLACH. 140 Nassau St., New York. Prospectus mailed free. 



THE CHEAPEST AND BEST 



IP 



PARK PLACE, NEW YORK 



FOR SALE. 



A GEOLOGICAL MAP OF THE STATE OF NEW 

 YORK, issued with legislative authority in 1842. Price $15. 



Please address L. \V. O., office Science, 47 Lafayette Place, 

 New York. 



AN ILLUSTRATED WEEKLY JOURNAL. THE SCIENCE 

 COMPANY, OWNERS AND PUBLISHERS. 



Officers and Directors. — D. C. Gilman, of Baltimore, President! 

 Simon Newcomb, of Washington, Vice-President; Gardiner G. Hub- 

 bard, of Washington : Alrx. Graham Bell, of Washington ; O. C. 

 Mafsh, of New Haven • T. W. Powell, of Washington; W. P. Trow- 

 bridge, of New York ; S. H. Scudder, of Cambridge. 



SCIENCE appears every Friday. Volumes begin in July and January. 

 Conimunications will be welcomed from any quarter. Rejected manu- 

 scripts will be returned to the authors only when the requisite amount of 

 postage accompanies the manuscript. 



Address all correspondence about contents of paper to 

 " Editor of Science," 



47 Lafayette Place, 



New York. 



Subscriptions.— In United States and Canada, $5 a year. 



In Great Britain and Europe, $6 a year. 



Address all financial correspondence to 



" Publisher of Science," 



743 Broadway, 



New York. 



The Treasurer of the Science Company will in all cases send 

 a receipt for money paid to the publisher. 



SUMMER COURSE Itt BOTANY. 



At the Botanic Garden of Harvard University, 

 Cambridge, Mass. 



The Course will begi?i Thursday, July 1, and 

 end Saturday, July SI, 1886. 



Instruction will be given in the Principles of Mor- 

 phology, Outlines of Descriptive Botany, and the Ele- 

 ments of Vegetable Physiology, by Prof. Goodale. 



Mr. F. L. Sargent will give instruction in Methods 

 for identifying Flowering Plants and the more com- 

 mon Cryptogamic Genera. 



The course is designed especially for teachers. Fee 

 for the course $25.00. For further information, address 



Mr. F. L. SARGENT, 417 Broadway, 



CAMBRIDGE, MASS. 



'jphe Travelers Insurance Company 



of Hartford, Conn., organized 1864, issues both Life Policies and 

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 diately on receipt of satisfactory proofs. 



Straight Cut Cigarettes. 



People of refined taste who desire 

 exceptionally fine cigarettes should use 

 only our STRAIGHT CUT, put up 

 11 satin packets and boxes of 10s. 20s. 

 50s. and 100s. 



14 FIRST PRIZE MEDALS. 



WM. S. KIMBALL & CO. 



