New Series 



Vol. XXXVII. No. 942 



Friday, January 17, 1913 



Single Copies, 15 Cts. 

 Annual Subscription , 85.00 



For many years we have carried in our New York house a 

 comprehensive selection of the Scientific Instruments made by 

 the well-known firm of 



CARL ZEISS, OF JENA 



which has been duly appreciated by industrial and educational 

 scientists desiring immediate delivery of their requirements, or 

 wishing: to inspect an instrument before purchasing. 



The most up-to-date models and new lines are promptly 

 added to our stock, to which we invite inspection. 



'pT«?=^ 



Literature descripti've of any ZEISS products 

 •will be gladly sent free upon request. | 



MICROSCOPES 



REFRACTOMETERS 



INTERFEROMETERS 



For Gas and Water 



HAEMACYTOMETERS 



ETC., ETC. 



Orders for duty free importation are executed as promptly as possible, 

 at duty free rates 



Headquarters for Educational and Industrial Laboratory Supplies. 



NEW YORK 

 205-211 Third Ave. 



PITTSBURGH, PA. 

 8035 Jenkins Arcade BIdg. 



..-^stnisn \nsii 

 JAN 1819: 



