Record. liii 



character. They could be seen while they were being photo- 

 graphed. They looked like little spheres of light, which 

 traveled over a non-conducting plate, formiug the insulation 

 of a condenser. They traveled very slowly among the sparks 

 of the ordinary disruptive discharge. Their speed was usually 

 at the rate of an inch in three or four minutes. Their tracks 

 showed with the greatest sharpness among the more indistinct 

 flashes of miniature lightning. They sometimes jump for a 

 quarter to a third of an inch, with such quickness that the 

 eye can hardly follow them. Five or six such spheres of 

 light sometimes appear at once, each following its own 

 track. Sometimes one will cross a track previously traoed by 

 another, but it never follows the track of another. 



By proper illumination of the room, the effects of the 

 spark discharge can be nearly obliterated in the negative, but 

 the paths of the ball discharges are not materially affected. 

 One negative thus treated had been exposed for thirty-five 

 minutes, and the ball lightning tracks were most elaborate. 

 The branching network of lines must have been produced by 

 hundreds of these little spheres. 



The same result can be attained by fixing the negatives 

 without any developing process. Everything then vanishes 

 from the plate but the tracks of the ball discharges. 



Professor Nipher stated that this phenomenon could not be 

 identified as the same thing as ball lightning, since the latter 

 had not been studied. But it responds to the same de- 

 cription in many ways. As soon as the ball lightning effects 

 appear, the behavior of the machine changes in a very re- 

 markable way. 



Mr. Koch exhibited an electric fire annunciator. 



Mr. Victor Goetz and Rev. James W. Lee, of St. Louis, 

 Professor George Lefevre and Mr. Charles Thorn, of Co- 

 lumbia, Missouri, and Professor C. S. Oglevee, of Lincoln, 

 Illinois, were elected to active membership. 



Six persons were proposed for active membership. 



