5oS, 



SCIENCE 



New Series. 



Vol. VIII. No. 192, 



Friday, September 2, 



Single Copies, 15 CTS. 

 Annual Subscbiption, $5.00 



General Electric Co/s 



FLUOROSCOPES 



PlatiDO=cyanide of Barium, or Tungstate of Calcium Screens. 



i">L<yy yv-ivi!^i i \juL( vacuum requlator. 



EFFICIENT. 



LONG-LIVED. 



ROENTGEN RAY APPARATUS of all kinds. 



Catalogue No. 9050. 



Candelabra, Miniature and Decorative Lamps. 



Catalogue 'So. 9044. 



EHisoQ Decorative aoil piiiiiatDre Lanip Departieiit, 



(.GENERAL LECTRIC COMPANY.) 



HARRISON. N. J. 



MINERALS. 



SPHERULITES from Colorado at from 30c. to 82 for 

 a specimen 4 inches in diameter, sections 50c. and 31.50. 

 TRIDTMITE from New Mexico, ?1.26. New lot of 

 fine CKSrSTAlLIZED COPPERS from Late Superior, 75c. to S30. CALCITE containing native 

 copper, 10c. to J1.50. MASSIVE DATOI.ITB, Lake Saperior, SI to S2. NATIVE SELVBK ON 

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WARD'S NATURAL SCIENCE ESTABLISHMENT, 18 to 28 College Ave., Rochester, N.Y. 



IVIAX KOHLi^ Ghemnitx^ Crerxnany^ 



FIRST EUROPEAN MAKER OF 



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Special Manufacturer of Roentgen X-Ray Outfits. 



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Price List No. 10 of Pliysical Instruments ; nearly 400 pages and more than 1300 engravings (in German, English 

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SS- BEFEREXCES FROM LEADINO EXPERTS. '&!. 



Representative: Nlessrs. EIMER & AMEND, 205-211 Third Avenue, New York. 



