124 TRANSACTIONS OF THE [mAY 9, 



Further Experiments in Connection with Vacuum Discharges. 



Dr. Pupin's paper was illustrated by photographs of experimental 

 and actual corona of the sun. 



Dr. Bolton asked what were the gases he introduced into the 

 vacuum flasks, and suggested that certain gases might produce light 

 more easily photographed, provided the mechanical effects sought 

 were secured. 



Dr. Pupin said he used ordinary air and alcohol vapor, the latter 

 giving a very white light. 



Prof. Rees spoke of the opportune character of Dr. Pupin's re- 

 searches in their bearing on the theory of Schaberle. 



Mr. J acoby exhibited a negative of the stars surrounding j3-Cygni, 

 which had been taken at Columbia College Observatory, April 19, 

 1892. A comparison of this negative with the results deduced 

 from Mr. Rutherfurd's negatives of the same stars showed that the 

 discrepancies between the latter and Argelander's Diirchmusteruvg 

 were due partly to omissions in the Durchmusterung and partly 

 to insufficient sensitiveness of Mr. Rutherfurd's plates. Attention- 

 was particularly called to the stars numbered 27 and 28 in Mr. 

 Rutherfurd's list. These two form a double on the Rutherfurd 

 plates; and while they are plainly separated on the latter, on the 

 Columbia College negative the image of the smaller star appears as 

 a sort of elongation of the larger star image. This appearance 

 may, however, be due to the enlargement of the images upon the 

 very sensitive dry plates. 



Vice-President Bolton resumed the chair, and the Academy 

 adjourned. 



May 9th, 1892. 

 Stated Meeting, 



Prof. J. K. Rees in the chair. Sixty persons present. 



The minutes of April 25th were read and approved. 



Morris Loeb, Ph.D., of the University of the City of New York, 

 was proposed as a Resident Member b}^ Dr. H. Carrington Bolton ; 

 the nomination was referred to the Council. 



The Secretary read the following papers by title : — 



