204 E.. H. Hall on a New Action of the 
tact was insured by pressing firmly down on each end of the 
strip of gold leaf a thick piece of brass polished on the under- 
side. ‘To these pieces of brass the wires froma single Bunsen 
cell were soldered. The portion of the gold leaf strip not cov- 
ered by the pieces of brass was about 54 cm. in length-and had 
a resistance of about 2 ohms. The poles of a high resistance 
Thomson galvanometer were placed in connection with points 
opposite each other on the edges of the strip of gold leaf mid- 
way between the pieces of brass. The glass plate bearing the 
gold leaf was fastened, as the first one had been, by a so 
cement to the flat end of one pole of the magnet, the other pole 
of the magnet being brought to within about 6mm. of the 
strip of gold leaf. 
The apparatus being arranged as above described, on the 
12th of November a series of observations was made for the 
purpose of determining the variations of the observed effect 
with known variations of the magnetic force and the strength 
of current through the gold leaf. 
eriments were hastily and roughly made, but are 
sufficiently accurate, it is thought, to determine the law of va- 
riation above mentioned, as well as the order of magnitude of 
the current through the Thomson galvanometer compared with 
the current through the gold leaf and the intensity of the mag- 
netic field. 
The results obtained are as follows: 
=i dan ee kas! 
vw. MM. 
0616 11420 H 00000000232 303000000000" 
"0249 Li240 “00000000085 829000000000" 
‘0389 11060 “ °00000000135 319600000000" 
0598 7670::* 00000000147 312000000000" 
0595 B00 :** 00000000104 326000000000" 
