Correspondence. — 115 
To experiment with this elegant little machine, the conductors for - 
receiving the electricity developed are fastened in the clamps BB; if 
these conductors communicate with the ovter and inner surfaces of a 
hey charge it as well as if the jar were put in connection 
with an ordinary electrical machine. If we connect with this apparatus 
the two balls of an electric egg, a series of sparks is produced, forming 
a true flame, poet si the negative to the sian pole, which de- 
onstrates once more the curious fact discovered by M. Neef, that 
electric light eepakik <Biaat at the mre pole of the pile. The 
fact is much more marked when a vacuu made ; as the air ges 
the “ee the igh becomes more distinct, pe when the vacuum ap- 
M, Sinsteden, who has paid much attention to subjects i a kind, 
has arrived at similar results. It was he who sug gested t ost im- 
of the t two eh gre a result some by enveloping each in two 
ed 
bi of tension, as if i In communication witb. an electrical ma 
" t, Mr. Henry and M, Riess have a long time since inde observa- 
pa of a similar character.t 
this machine may also give shocks, By fastening in the clamps BB, 
: «extremities of the conductors which end in the handles, and taking 
( t 
connection with fps 8 facts Wiseh have been stated, it is important 
to mention 4 singular observation made by M. Ru Ruhmkorff, which he 
allo sin ce brought out It h has been seen that the hammer and anvil 
are covered with aetiok foil. But if ca gaaere be substituted, no 
Sensible, sign of static lsainalty is. observed, a ~ hardly any sensation 
of felt. on touching the conductors. with the tongue. Sinsteden 
ewe this singular. effect to the greater pen ate of silver and 
Mae ee is less Resiataagr This does not appear to us admissible, 
or bserved that copper, ‘which is nearly as good a 
eri a oa ial affords nearly the same effects as Pp atinum. 
the fo 
Rives phan apical yy Miraud.—An electro- 
g- 2) is eaieed horizontally, or vena on a flat surface, 
con i connection on one s of the poles of a gal- 
on the other with a ‘fexible “apeiog, GH, which car- 
ies at Ca a plate of soft iron. This spring rests against another spring 
So 
betwee of M. Ruhmkorff and the compan d electro- 
s d ames De (Song ve se apparatus appeas 10 o be “hut little 
: ae & creel poe Journal, vo! pa, 252, 1839.—. 
endorif’s jie May, 1852, Fer 
5: 
a of Dr, er pane Rages ea we be added. There are many points of 
