SCIENCE 



Friday, March 2, 1900. 



Single Copies, 15 cts. 

 Annual Subscription, SB. 00 



V/M. OAERTNER «& CO. 



Astronomical and Physical Apparatus 



152-158 EAST 56th ST., CHICAGO 



SPECIALTIES 



Stad 



SIMPLE MICROMETER lor use with 

 our Standard Microscope and Telescope 



ftRD Apparatus of New and Improved Designs 

 Reading Microscopes and Telescopes 

 Astronomical telescopes Heliostats 



Spectroscopes Dividing Engines, Comparators 



MicHELSON Interferometers General Laboratory Apparatus 



bolometers Universal Laboratory Supports 



MIITIATXJKE IITCANDESCENT LAMPS. 

 MINIATURE LAMP RECEPTACLES. 

 X-RAT TUBES AND APPARATUS. 

 FLUOROSCOPES — . 



Catalogues on Application. 



Edison Decorative and Miniatnre Lamp Department, 



(General. Electric Company), 



HARRISON, N. J. 



"¥^^^Q[C< "TT" TT^X^hff ^'^^ Green River, Wyo., fish of the Bridger Eocene period are 

 A. ^Jr^^^^A..^^ A. A.^^^^% very handsomely preserved and make unusually appropriate, 

 - and striking wall pieces for the naturalist's library. 



We have them in quantity and can sell at from %\ to $16 each. Framing extra if desired. 



WARD'S NATURAL SCIENCE ESTABLISHMENT, 30 to 40 College Ave., Rochester, N.Y. 



Catalogue X 



is a complete price-list of Ammeters, Voltmeters, Wattmeters, 

 etc., made by the Weston Electrical Instrument Co. 



As Selling Agent for these Standard instruments I give 

 special care to college business and bold myself ready to quote 

 lowest prices to educational institutions. 



Ask for Catalogue X and write me in detail about your re- 

 quirements. 



JAHES Q. 



1034 Drexel Building 



BIDDLE 



PHILADELPHIA 



\9^J 



NatloS^ 



^ 



