ELECTRICITY OF THE BLOWPIPE FLAME. 393 



Buff, have published very interesting results on the effects of 

 flame as to conduction and production of voltaic electricity. 



The experiments of which I am about to give a notice 

 were for the greater part made before I had read the papers 

 of the two last authors ; and while they differ in results from 

 theirs, they give a means of producing a voltaic current from 

 flame far more distinct and powerful than any which I have 

 tried or read of. 



The flame I have worked with is that of naphtha or spirit 

 of wine, urged by an ordinary glass-worker's blowpipe ;' and 

 with a galvanometer, the needles of which are barely deflected 

 to 2 by any current which I can procure by the flame of a 

 common spirit-lamp, I can by the blowpipe flame procure de- 

 flections of 20 or even 30, and with great certainty and 

 uniformity of direction. 



I am not aware that the blowpipe flame has ever been used 

 for the production - of electricity, though I see by M. E. Bec- 

 querel's recent paper that M. Becquerel, sen., has used it as a 

 means of adventitiously heating a spiral placed in another 

 flame. 



Two platinum wires of six inches long and -^th of an inch 

 diameter have their ends formed into coils of th of an inch 

 long and wide ; these wires are attached to copper wires in- 

 sulated by glass stands, and having their farther extremities 

 connected with a galvanometer. My galvanometer is by 

 Ruhmkorff ; the wire is not as long as those now constructed, 

 being only 544 feet, but I have so magnetised the needles as 

 to render them highly astatic ; they take four minutes to make 

 one oscillation. 



An additional binding screw is connected with the wire at 

 54 feet of its length, so that I can ascertain by the same 

 instrument the effect of a slighter resistance. 



When the flame of a spirit-lamp is urged by the blowpipe 

 one of the above-mentioned coils is placed in the full yellow 

 flame just beyond the apex of the blue cone, and the other 

 near the orifice of the brass jet, or at what may be called the 

 root of the flame, just beyond the base of the blue cone, the 

 distance ^between the two coils being 2\ inches. The coil in 

 the full flame is at a white heat and brilliantly incandescent, the 



