SCIENCE 



New Series 



Vol. LIV, No. 1408 



Friday, December 23, 1921 



Single Copies, 15 Ors. 

 Annual Subscription, 86.00 



A full line of polari- 

 scopes and accessories in 

 stock for immediate 

 shipment. 



The accessories include 

 polariscope tubes, 

 lamps, etc. Quartz 

 plates can usually be 

 supplied, present price 

 $30.00. 



Polariscopes are at 

 piesent in stock for 

 prompt shipment at the 

 following prices : 



No. 5440 either S& H. or Pellin makes $ 300.00. 



No. 5444 for tubes up to 400 mm 350.00. 



No. 5445 Bausch & Lomb polariscope, for tubes up to 400 mm 525.00. 



No. 5446 S& H., triple field for 200 mm. tubes 375.00. 



No. 5456 Half shadow with Lippich polarizer, for tubes up to 400 mm 475.00. 



No. 5480 Landolt, with Lippich triple field polarizer for tubes up to 220 mm. 500.00. 



Above numbers are taken from our AA catalog. Write for section of catalog 

 or additional information. 



AND ^ imiiiii I I i m i M 



imEr ^^mend 



NEW YORK, N. Y. V^^^ PITTSBURGH OFFICE 



3rd Ave., 18th to I9th St. NJ!L^>^ 4048 Jenkins Anade 



Washington, D. C. Display|Rooin, Suite 601, Evening Star B'Id'g., 

 Penna. Ave. & 11th Street 



