ADVERTISEMENTS. 



JAMES W. QUEEN & CO., 



OPTICIANS : 924 Chestnut St., Phila. - 



Manufacturers and Importers of 



PHYSICAL AND CHEMICAL APPARATUS, 



New Toepler Holiz Electrical Machines, Instruments of Precision, Electrical 

 Test Instruments, Spectroscopes and fine Optical Apparatus. 



MiCROSCOPES AND ACCESSORIES, 



Mathematical Instruments, Spectacles, Telescopes, 

 Photographic Cameras, etc., and all kinds of 

 Optical and Scientific Instruments. 



Abridged catalogue containing list of 

 our 16 catalogues sent on application. 



ACWE wo. 4. MICROSCOPE 



JA3.'.V.QUEErjS<C0.P;ill.A 



W. H.WALMSLEY&CO. 



SUCCESSORS TO 



K. & J. BECK, 



1016 Chestnut Street, Phila. 



Microscopes and all Acces- 

 sories and Apparatus. Pho- 

 tographic and Photo-Min- 

 fraphic Apparatus and Out- 

 ts. 



Spectacles, Eye Glasses, 

 Opera and Marine Glasses, 

 etc., etc. 



Illustrated Price List mailed 

 free to any address. Mention 

 Science in corresponding with 



^■^i^. 



T'he Travelers Insurance Company 



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

 and A ccident Policies. Only large accident company in America. 

 Only $5 a year to professional and business men for each f 1,000 

 insurance, with $5 weekly indemnity. Has paid policy-Iiolders 

 nearly $11,000,000. All policies non-forfeitable. All claims paid, 

 without discount, and immediately on receipt of satisfactory proof. 



QUSTAV E. STECHERT, 



766 Broadway, Ncv York. 

 Itnporter of Scientific Books and Periodicals. 

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

 King William Str., Strqnd. 



DIAMONDS. 



A very large stock and great variety of diamonds constantly orj 

 hand. An assortment will be sent for examination in this city or 

 vicinity when reliable parties desire it. WALTHAM 

 WATCHES, RICH JEWELRY, FRENCH MARBLE 

 CLOCKS, BRONZES, STERLING SILVERWARE, ETC. 



2 MAIDEN LANE, N. Y. 



STUART & SHEPARD. 



HOW TO STRENGTHEN THE MEMORY. 



By M. L. HoLBROOK, M.D. 



Science says: "It was with this prejudice that we took up 

 Dr. Holbrook'sbook; but the perusal of the preface and the in- 

 troductory sections alone proved that for once at least a prejudice 

 against books on training the memory was unfounded. Dr. Hoi- 

 brook writes with a physiological and psychological knowledge of 

 his subject, and he treats it in a plain, straightforward, common 

 sense way." 



Price by Mail, $1,00. 



M. L. HOLBROOK CO , 13 Laight St., New York. 



KIMBALL'S SATIN STRAIGHT CUT 

 CIGARETTES. 



People of refined taste who desire 



exceptionally fine cigarettes should use 



_ only our STRAIGHT CUT, put up 



i\ in satin packets and boxes of 10s. 20s. 



50s. and loos. 



FIRST PRIZE MEDALS. 



WM. S. KIMBALL & CO. 



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The American Investment Company, of Em- 



mettsburg, Iowa, with a paid-up capital Of $600,000, 

 surplus $75,000, offers first Mortgage Loans drawing 

 seven per cent., both Principal and Interest fully gfuar- 

 ranteed. Also 6 per cent. lo-year Debenture Bonds secured 

 by 105 per cent, of first Mortgage Loans held in trust by the 



Mercantile Trust Company, N. Y. 5 per cent, cer- 

 tificates of deposit for periods under one year. Write for full 

 information and references to the company at 1 50 NaSSau 

 St., N. Y. A. L. Ormsby, Vice-Pres. and General Manager. 



