486 SCHLESINGER-NEW PHOTOGRAPHIC INSTRUMENT. 



the same declinations. The instrument is intended for cooperation 

 with the meridian circle in the determination of the positions of 

 several hundred comparison stars in a narrow zone, upon which in 

 turn can be based the compilation, by photographic observations, 

 of zone catalogues of many thousands of stars. 



Allegheny Observatory of the 

 University of Pittsburgh. 



