Transactions of The Royal Society of Canada 



SECTION III 

 Series III DECEMBER 1914 Vol. VIII 



Note on the Possible Effect of a Longitudinal Magnetic Field on a Radial 

 Current in a Bunsen Flame. 



By A. A. Scott. 



(Presented by Dr. A. S. Eve, F.R.S.C.) 

 (Read May 28, 1914) 



In the following investigation, although no positive results were 

 obtained, it was thought advisable to place on record the magnitude 

 of the various quantities entering into the experiment for the benefit 

 of workers in the same field. 



Strutt 1 has recently shown that the difference of potential ne- 

 cessary to produce a discharge of electricity between a long cylin- 

 drical electrode and an axial electrode in an exhausted vessel is greatly 

 diminished by a longitudinal magnetic field. Horton 2 has made a 

 similar experiment using a hot platinum strip as an electrode. 



It seemed possible that an effect might be obtained even at 

 atmospheric pressure when the flame of a Bunsen burner was employed 

 as a conducting medium. Accordingly the apparatus illustrated 

 herewith was arranged. (Fig. 1) 



The flame of a Bunsen burner was surrounded by a cylinder of 

 brass gauze in contact with the flame. A brass rod occupied the 

 axis of the cylinder. An electromagnet was placed in such a position 

 that a longitudinal magnetic field could be produced in the flame by 

 means of annular pole pieces. The gauze and the rod were connected 

 to a battery, a moving coil galvanometer and a reversing key through 

 a resistance of thirteen megohms. The gauze and the pole pieces 

 were insulated with mica. 



The results for an unsalted flame are shown graphically by the 

 following curves. The abscissae represent volts and the ordinates 

 divisions of the galvanometer scale. Small currents were obtained 



1 Strutt, Pro. Roy. Soc, vol. lxxxix, p. 68, 1913. Townsend, Phil. Mag., Oct. 

 1913. 



2 Horton, Phil. Mag., Nov. 1913. 



Sec. Ill, 1914—9 



