J. Trowbridge—Electrical Condition of Gas Flames. i 
generally negative. By placing a setts isle upon the prime 
conductor of an electrical machine, he was enabled to change 
the jecuiion of the air from a positive to a negative state and 
the reverse. He —— separates 8 results obtained from 
the idioelectric effect of the flame, w he states, in no case 
gave a tension equal to siaeda pole of a Daniel's element. 
uring the past ——— observations made in the laboratory 
tend to confirm these views. ave, however, found on some 
days the air eras octal positive. The room is in the 
north-west corner of the building, and there was a strong north- 
west wind blowing at the times this was observed. I noticed, 
also, while experimenting with the flame of a Bunsen burner 
placed near ‘the water drop Aen used by Sir William Thomson 
in investigating the electrical state of the atmosphere, that the 
positive charge of the air in the neighborhood greatly decreased, 
and in some Instances became feebly negative, by the presence 
of the flame. 
pelo lead : 
1. The flame of a Bunson burner is negative while positive 
electricity accumulates on the burner itself, if it is a con- 
ductor. With orifices made of non-conductors, no charge was 
pera Anaya the tip. 
e stratum of air in contact with the outer cone of flame 
nee ‘a chily charged with positive electricity. The partly con- 
gas of the interior cone is neutral. 
8. The presence of flames tends to change the nature of the 
atmospheric electricity at the given place, reducing a positive 
tension to a feebly negative one. 
