154 Intelligence and Miscellaneous Articles. 



The following are the results which 1 have obtained in testing* the 

 electrical condition of the flame of a Bunsen burner with a Sir Wil- 

 liam Thomson's quadrant electrometer. The degrees given refer to 

 the arbitrary divisions of the scale, upon which a spot of light is 

 reflected from the mirror of the instrument. 



Upon connecting the testing-plate of one pair of quadrants of the 

 instrument with the flame, while the other pair were connected with 

 the metallic burner and with the earth, the flame was found to be 

 negatively electrified. 



The following are some of the experiments, selected from a series 

 that were made. 



Exp. 1. Flame 12 centims. high ; plate at the height of 7 centims. 

 A negative indication of 130°, very steady. 



Exp. 2. A platinum wire, substituted for the plate, and meeting 

 the flame 3 centims. above the burner, gave a deflection of 30° in a 

 negative direction. 



Exp. 3. With the testing-plate just above the tip of the flame, 

 the instrument showed a positive deflection of 70 to 80 degrees. 



Exp. 4. With the testing-plate 5 millims. from the outer surface of 

 the flame, on all sides, a feeble positive charge was obtained, the air in 

 contact with the flame being apparently charged positively, the indi- 

 cation in no case exceeding fifty or sixty degrees on the scale of the 

 electrometer. 



Exp. 5. The metallic tip of the burner w^as found to be charged 

 positively, giving an indication closely agreeing in the number of 

 degrees with that corresponding to the negative indication of the 

 flame. This indication was quite constant. 



Exp. 6. When a glass tip was substituted for the metalHc tip, no 

 charge was found upon it. This was the case when any non-con- 

 ducting body formed the tip. 



Exp. 7. A glass tip having been substituted for the metallic one, 

 a platinum wire was inserted below the oriflce and carefully pushed 

 upward until it occupied the centre of the interior cone of flame. 

 A very feeble indication of negative electricity was the result. 



While, with the Bunsen burner, the flame and the metallic tip are 

 in decided electrical opposition, the one having a negative charge 

 and the other a nearly equal positive charge, in spirit-flames the 

 two opposite states recombine, the wick of the lamp and the fluid 

 contained in the vessel connecting the two charges. The flame, 

 therefore, merely takes the potential of the atmospheric electricity 

 at the place where it is situated. 



The electrical condition of the flame of a Bunsen burner when 

 tested by a sensitive galvanometer gives in the main the same results 

 as those obtained by Prof. Buff from spirit-flames. The quantity of 

 electricity in the current passing from the flame to the tip is exceed- 

 ingly small ; whereas we have seen above that the terminal immersed 

 in the gas-flame has a tension a little exceeding that of the negative 

 pole of a Daniell's element. 



The air in the room, at the time the above experiments were first 

 performed, was charged positively to about the tension of the positive 



