SCIENCE. 



in 



Electrical Batteries for Medical Purposes. 



J HE ^iY^TJE^N J^LECTFflC ^ANUFACTUF(IJ^q pO. 



CHICAGO, 



NEW YORK, 



Manufacturers of and Dealers in 



STATIONARY GALVANIC BATTERIES, PORTABLE HIG 

 ELECTROMOTIVE FORCE BATTERIES, CHLORIDE 

 OF SILVER BATTERIES, GALVANO-CAUTERY 

 BATTERIES, FARADAIC BATTERIES, POCKET 

 BATTERIES, BATH APPARATUS, AND 

 ELECTRODES. 



Dr. Butler's Plumbago Rheostat, 



PLIABLE SPONGE ELECTRODES, &c, &c 



EDISON'S 



Electric Pen & Duplicating Press, 



yin f xtremely Useful Jnvention 



FOR 



DUPLICATING WRITTEN OR PRINTED MATTER. 



CATALOGUES ON APPLICATION. 



Address all Orders to 



Western Electric Man'f'g Co. 



38 Union Square, 

 — NEW YORK — 



CITY. .^PRICE 



8,000 Copies from a Single Writing, at the Rate of 400 an Hour. 



li is successfully used by Schools, Colleges, Banks, Commission Houses, Mercantile Firms, Lawyers, 

 linisters, Copyists, and every person or firm desiring a number of duplicates of any document. 



10,000 fens now in JJse and i\e Pemand £teadily jncreasing! 

 No. 1, $25.00; No. 2, $30.00; No. 3, $35.00, 



Full Description and Samples of Work sent on Application, 



EDISON'S ELECTRIC PEN AND PRESS, 



38 Union Square. New York Citv. 



JAMES W. QUEEN & CO. 

 OPTICIANS, 



924 Chestnut St., Philadelphia, Pa. 



The Few $50 Microscope 



{See Illustration.) 

 Write for Catalogue of Magnifying 

 Glasses, Microscopes, Microscopic 

 Objects, Microscopic Books, Mi- 

 croscopic Object Glasses, Micros- 

 copic Accessories, Mounting Ma- 

 terials, &c, and mention this 

 YJournal. 



Catalogues in 4 parts as follows : 

 Part 1st, Mathematical Instruments. 

 " 2d Optical Instruments. 

 lk 3d Magic Lanterns and Slides. 

 " 4th Physical Instruments. 



From our own experience we can confidently recommend to all 

 Nervous and Debilitated persons 



dr. crosby's brain and nerve pood, 



The Vitalized Phosphites, 



BECAUSE 



It is largely prescribed by Physicians. 



It is much taken by Clergymen, School Teachers, Lawyers, 

 Students, and all who over-use the brain. 



It cures Nervous Disorders, especially where it exists with Debility 



By curing Debility, it prevents Consumption. 



Many who have been great sufferers with Nervousness, Sleep- 

 lessness and Neuralgia, speak of it in the highest praise. 



It gives vigor to the mental and bodily growth of children, and 

 makes a less fretful and happier childhood. 



Every Wholesale Druggist in the U. S. buys it in large quantities. 



SCIENCE 



A. WEEKLY JOURNAL OF SCIENTIFIC PROGRESS 



Vol. II, No. 54, July 9, 1881. 



CONTENTS. 



Observations upon the Comet at Princeton, by Prof. C. A. Young ; Primordial Cosmic Rings, by Edgar L. Larkin ; 

 Seismology in Japan ; The Use of Water as a Fuel, by Dr. George W. Rachel ; Dr. Gunther's Ichthyology, by Prof. 

 Theod. Gill ; Descartes and the Barometric Theory ; Correspondence : On Ether, by B.; The Comet, by Edgar L. 

 Larkin. 



Subscription Four Dollars a Year. 



Single Numbers, Ten Cents. 



