SCIENCE.— AB VER TISEMENTS. 



RARE MINERALS. 



THAUMASITE, from Paterson, N. J., a sulphate, silicate and 



carbonate of calcium, pure white, 2Sc. 

 EKDEMITE, bright yellow on red wulfenite, Arizona, SOc. 

 NATIVE ARSENIC, Japan, % to J^-iuch crsytallized balls, 



25c, 3Sc. 



Collections for Schools. 



ALPHA COLLECTION, twenty-flve specimens in trays, con- 

 tained in a neat wooden box and accompanied by a i6- 

 page guide book (XIII., Guide ior Science Teaching, Bos- 

 ton Society of Natural History), Price, complete, $(.00. 



CABINET COLLECTIONS, 100 specimens, small size, $5.00. 

 100 specimens, large size, $10.00. These specimens are 

 each accompanied by a label giving name, system of 

 crystallization, chemical formula, and locality, and make 

 a good working collection for a student. 



EXCELSIOR COLLECTION for high schools and colleges. 

 200 specimens, nicely mounted on wooden blocks, with 

 beveled fronts for receiving labels. Price, packed, 

 $100.00. mchool Bulletin inst out. 



Loose Crystals. 



Small packages of free crystals for crystallographio study 

 may be sent for inspection by mail at small coat. Ap- 

 proval boxes of cabinet specimens by express or freight. 



ROY HOPPING, 



MINERAL DEALER, 



504-506 Liberty Building, 



Liberty and Greenwich Sts. 



NEW YORK. 



McGILL UNIVERSITY, MONTREAL, 



CHAIR OF ZOOLOGY. 



The Governors of McGill University are prepared to re- 

 ceive applications for appointmeut to the newly-founded 

 Professorship of Zoology. Salary, $2600 per annum. Candi- 

 dates are requested to forward applications, with any testi- 

 monials and references they may desire to submit, on or be- 

 fore first of June to 



Secretary, McGill University, Montreal. 



P'imhi>!<>n Cnceilc •*■ l^^S^ collection of Upper 

 uaHIUridll rUoSllo. Mississippi Cambrian fossils 

 from the St. Croix (Potsdam) sandstone for sale. Mostly 

 Trilobites. Send for low prices. 



W. A. FINKELNBURG, WINONA, MiNN. 



Dec. 1, 1896. Just Publislied. Sixth Edition of 



THE MICROSCOPE ^S^uTE^IfoT" 



By SIMON HENRY OAQE, Professor of Microscopy, His- 

 tology and Embryology in Cornell University and the 

 New York State Veterinary College, Ithaca, N. Y., U.S A. 

 Sixth edition, rewritten, greatly enlarged, and illustrated 

 by 166 figures in the text. Price, $1 .50, postpaid. 



COMSTOCK PUBLISHING CO., Ithaca, N. Y. 



Harvard University. 



Lawrence Scientific School 



OFFERS COURSES IN 



C?lvll Engineering, 



Mechanical Engineering, 



Electrical Engineering, 



Mining Engineering, 



Arcbiteciure, 



Chemistry, 

 Geology, 



Botany and Zoology, 

 General Science, 



Science for Teachers, 



Anatomy and Physiology (as a preparation for Medical Schools) 



For Desoriptive Pamphlet apply to 



M. CHAMBERLAIN, Secretary, 

 N, 8. SHALER, Dean, Cambridge, Majss 



A7^/c 



For Brain-Workers, the Weak and 

 Debilitated. 



Horsford's Acid Phosphate 



is without exception, the Best Remedy 

 for reheving Mental and Nervous Ex- 

 haustion; and where the system has 

 become debihtated by disease, it acts 

 as a general tonic and vitalizer, afford- 

 ing sustenance to both mind and body. 



Dr. E. Cornell Esten, Philadelphia, Pa., 

 says : "I have met with the greatest and most 

 satisfactory results in dyspepsia and general de- 

 rangement of the cerebral and nervous systems, 

 causing debility and exhaustion." 



Descriptive pamphlet free on application to 

 Rumford Chemical Worlds, Providence, R. I. 



For sale by all Druggists. 



Beware of Substitutes and Imitations. 



lE'ojc la CJexi'ts 



I will mail a finely finished original photo, 

 cabinet size, of Sioux Indian Cliief, SITTINO 

 BULL, witli his Signature. Have 200 sub- 

 jects, all different, of leading Western Indians. 

 First-class wor''^. Cabinet Size for 10 cents each. Some sent 

 on selection. Give reference. After seeing sample you will 

 want others' Indian Costume, Ornament! and Weapons. 

 15 000 Flint Stone Ancient Indian Relics. 100,000 Mineral 

 and Fossil Specimens. Catalogue ior stamp. 13th year. 

 Ii. W. STILWEIili, Deadwood, South. Dak. 



HOUGH'S 'mRICAN WOODS" 



A publication illustrated by actual specimens. 



WOODS FOR THE STEREOPTICON 



Enabling you to show upon the screen characteristic 

 structures projected from nature itself. 



WOODS FOR THE MICROSCOPE 



Sections 1-1200 in. thick showing three distinct views oi 

 grain under each cover glass. 



WOOD SPECIMENS FOR CLASS USE 



Nothing equals these tor use in the class-room. 



VIEWS OF TYPICAL TREES 



From Nature, photographs and stereopticon views. 



WOODEN CROSS-SECTION CARDS 



Perfectly adapted to printing (with type or steel plate), 

 painting, India ink work, etc. 

 If you are interested in wood or trees in any way send for 

 our circulars and sample specimens. 



.Address R. B. HOUGH, Lowville. N. Y. 



