342 J. Nicklés on Different Applications on Magnetic Aitraction. 
Under the new conditions, obstacles were encountered which 
were unknown in my laboratory researches. Still, without modi- 
fying the wheels, which was not allowed, I undertook to apply 
the method of magnetization above described. 
As the experiments have led to some curious results not devoid 
of scientific interest, I will enter into some details which may at 
will be the battery, and particularly the helices. The helices 
when once constructed must remain as they are, while, by the 
different modes of combination of which a battery is susceptible, 
we can always apportion more or less the tension of the fluid to 
the resistance to be overcome. 
Helices of Magnetization. 
Considering only the works hitherto published on magnetiza- 
tion, the nature of helices should be easily resolved. In fact, ac- 
cording to Dal Negro, Fechner, Lenz and Jacobi,* : 
1. The magnetic intensity developed is proportioned to the in- 
tensity of the current. 'The nature of the application is opposed, 
it is true, to a galvanic development of great power; but it may 
be supplied, if, as Lenz and Jacobi conclude 
he attraction is proportioned to the intensity of the current 
multiplied by the number of turns in the helix ; and with much 
more reason, if as says M. Dub 
The magnetic attraction developed, is proportional to the 
square of the current multiplied by the square of the number of 
turns of the spire ; alaw which ten years since Mr. Joule { ex- 
pressed in the formula, M=E2W2, M, representing the magnetism 
eveloped, E, the quantity of electricity in activity ; and W, the 
length of the conductor. 
Moreover, MM. Lenz and Jacobi, say that “the section of the 
conducting wire is without influence on the magnetizing force, 
provided the galvanic intensity does not vary ;’ and as the resist- 
ance offered by the conductors is proportional to their length and 
inversely as their section, a battery and helix may be constructed 
such that the number of turns of the helix shall be the greatest 
possible. Happily [have had occasion to observe that Mr. Joule’s 
formula is not exact, or at least does not apply in such a case as 
this; the law of magnetic maximum of M. Miiller is on the other 
side opposed to it. 
These doubts and contradictions, and the necessity of further 
experiment, complicates much the problem in hand. Ihave how- 
* Poggendorff’s Ann., xlvii, 225. + Poggendorff’s Ann, (7) hexxi, 46. 
¢ Phil. Mag., [4] vii, 309, and Annals of Elect., i, 470. 
