THE 



AMERICAN JOURNAL OF SCIENCE 



l\ 



[THIRD SERIES.] 



Art. XXXII. — On the Action of Vacuum Discharge 

 Streamers upon each other; by M. I. Pupiist, Ph.D., of 

 Columbia College. With Plate XII. 



- Fv 



Various phenomena which I observed in the course of an 

 investigation on the coronal effects produced by electrical dis- 

 charges through rarefied gases, led me to the belief that under 

 certain conditions two electric current filaments in a rarefied 

 gas may act upon each other oppositely to the direction of 

 their mutual electrodynamic. action, and that this additional 

 action may sometimes be far predominant over the electro- 

 dynamic action ; that is to say, we have a strong repulsion where 

 electrodynamic action would produce an attraction. A brief 

 account of these investigations was given on Feb. 8th, before 

 the Astronomical Section of the New York Academy of 

 Sciences. The following paper is limited to the description 

 of the experiments by means of which the existence of the 

 above mentioned action was definitely proved. 



Pig. 1 represents the apparatus first employed. Four glass 

 bulbs, A, B, C, D, each having a capacity of about a liter, are 

 connected by four glass tubes of small bore to a glass reservoir 

 E. A stopcock F serves to connect the apparatus to a mer- 

 cury pump. The reservoir has a diameter of 10 cm and a length 

 of 22 cm . The mouths e, f, g, h, oUhe four narrow-bore tubes 

 form a square whose side is 10 cm long. The bulbs are covered 

 with tinfoil and the tinfoil is then well coated with paraffin. 



Am. Jour. Sci— Third Series, Vol. XLIII, No. 256.— April, 1892. 

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