SCIENCE.— AD VER TISEMENTS. 



cAbsoIutely Reliable Alivay^ 



emin^ton 



Standard Typewriter. 



NEW MODELS. 

 Wyckoff, Seamans & Benedict 



327 Broadway, New York. 



THIN SECTIONS (Microscopic) 

 OF ROCKS, MINERALS, FOSSILS, ETC., 



carefully mounted, and for sale at selection from list or in ar- 

 ranged collections, with descriptive commentaries (prepared by 

 experienced Ijthologistp). CorrL-sponding rock specimens. 



GRINDING MACHINES 



with latest improvements and fitted to foot power, electric motor, 

 etc. Of best construction, but low in price; adapted to slicing 

 and polishing all roct substances hard or soft ; witb suitable laps 

 for preparation of thin sections for m'icroscope. Send for circulars, 

 GUSTAVUS D. JULIEN, 932 Bloomfield St., Hoboken, New Jersey. 



The Microscope and Microscopical Methods 



Sixth Edition. Fully Illustrated. 

 By SIMON HENRY GAGE, of Cornell University. 



This book is a product of the laboratory and is designed 

 for actual laboratory use. It deals with the modern micro- 

 scope and its accessories, microscopical methods, including 

 photo-micrography, etc., and has in view the especial needs 

 of students, teachers and professional men. Postpaid, $1,50 

 COMSTOCK PUBLISHING CO., Ithaca, N. Y. 



DYSPEPSIA 



Horsford's Acid Phosphate 



reaches various forms of Dys- 

 pepsia that no other medicine 

 seems to touch. It assists the 

 weakened stomach and makes 

 the process of digestion natural 

 and easy. Pleasant to take. 



For sale by all Druggists 



NEW CATALOGUE. 



We have recently issued a new edition, revised and en- 

 larged to 64 pages, of our catalogue of 



Books on Cbetnistry, Clieinical 

 Teclinology and Physics. 



It is arranged by subjects, and includes all the standard 

 books in Chemical" and Physical Science, as well as the re- 

 cent literature up to date. 



A copy of this Catalogue will be sent free by mail to any 



D. Van Nostrand Company, 



Publishers and Importers of Scientific Books, 

 23 Murray St. and 27 Warren St., New York.. 



WJVl. GAERTNER & CO., Scientific Instrument Worlis 



Manufacturers of ASTRONOMICAL AND PHYSICAL, APPARATUS of modern design and lilgli-grade work- 



mansliip. SPECIALTIES : Equatorial Telescopes, Micrometers, Spectroscopes, Linear and Circular Dividing 



Engines, Comparators, Michelson Interferometers, Bolometers, etc., etc. General Laboratory Apparatus. 



Universal Laboratory Supports. „., , ^ ,. „.^.^ „^, .,...- 



Heferences from Leading Seientists. Catalogue on Application. 



Extra Fine Cabinet Specimens. 



Rare Species. Loose Crystals. 



Cheap Educational Specimens. 



SrsTEMATic Collections. 



Blowpipe Minerals by the Pound. 

 Our Stock greatly enriched by Mr. Englishes Recent Tour of Europe. Write for full particulars, and for free 

 Price Lists and Bulletins. 124 pp. Catalogue (87 cuts) describing every species, 25c. in paper, 60c. in cloth. 



GEO. L. ENGLISH & CO.. Mineralogists. 64 E. 12tli St., New York» 



