PRITCIIARD S WEDGE PHOTOMETER. 



30 





chart of the region following y Pegasi. 



They are designated by corresponding 



On the original chart their magnitudes were given as follows, 

 viz.: No. 1, 10th; No. 2, 11th; No. 3, 11th; No. 4, 11th; No. 5, 11th; and No. 6, 



numbers in Fig. 1. 



1 3 th. 



Of course these magnitudes, shown by the symbols on the chart, are only 



intended to be roughly accurate, no gradations smaller than whole magnitudes 



being indicated. The 



tained in the original chart, but added by the Princeton telescope 



points surrounded by dotted circles indicate stars not con- 



The observa- 



2 



m 



S. 5 







N.5 



2 



Region following y Pegasi. Photometer Stars. Octorer, November, 1SS6 



3 



m 



2p 20' 



2 m 40* 



Scale of magnitudes 



10 



11 



* 



12 



3° 

 13 14 



3° 20' 



Fig. 1. 



tions 



were made in 



d 3, then fi 



the following order 



each of 3, 2 



d 1 



F 



fi 



extinctions of Nos. 1, 2, 



reverse 



ord 



th 



whole thirty ex- 



tinctions taking about an hour and a quarter, 

 made of the smaller stars, 4, 5, and 6. On the first 



Then five extinctions ench were 



- 



only No. 5 



i observed. 



In reducing the 



observations, the mean of 



ty readings of the first 



taken, and the mean of 



the readings of each of the stars was compared 



th th 



is mean 



In the table bel 



2> 



etc. are the diff 



between th 



for each star and the mean of Nos. 1, 2, and 3 



r are the differences betw 



the individual 



nd 



mean 



for the 



four 



evenings. A plus sign in the A column denotes that the star was brighter than 



