ELECTRO-MAGNETISM AS A MECHANICAL POWER. 533 
upon the latter. But an adhesion which continued after the ces- 
sation of the magnetizing currents then contributed to diminish the 
mechanical effect; whilst in the preceding arrangement the adhesion 
not only ceased, but to a certain point changed to repulsion, with the 
same rapidity with which the current, scarcely interrupted an instant by 
the action of the bascule, precipitated itself (the communication being 
inverted )into the middle spiral, ina direction contrary to its original one, 
resuming its ordinary course in the two other spirals. 
The motion of the lever and of the regulator, resulting from. this 
arrangement, is perfectly free ; at first rather slow, it soon and by de- 
grees acquires the maximum of velocity which the energy of the cur- 
rents producing it allows of,—a velocity which is afterwards maintained 
equal to the intensity of the current itself, and as long as the latter 
remains in action*. 
I shall say nothing at present respecting some observations which I 
have on this occasion collected, upon the employment of different acid 
and saline solutions, and of sea water. 
It is not without especial interest that we contemplate these new 
effects of a force developed in so singular a manner from the masses 
of bodies; and it is difficult not to be carried away by flattering 
anticipations respecting the ulterior applications which the acquisition 
of this mysterious motive force suggests}. 
The dimensions of the apparatus which has just been described are 
small, and such as the, current produced by fifteen elements of nine 
square inches can put in motion. The electro-dynamic cylinders, which 
principally determine the limits of the mechanical effect, are one deci- 
metre in length and a centimetre and a half in diameter; these are sur- 
rounded by a wire coiled in a spiral, the length of which is 40 metres, and 
half a millimetre in diameter. The lever is of wood; the upper and lower 
arms are respectively 35 and 7 centimetres long; the amplitude of its 
oscillations is 15°, Lastly, the regulator weighs 24 kilogrammes; and 
the total weight of the mechanism is about 5 kilogrammes. 
Considerations which readily presented themselves regarding the 
relations between the maximum of the magneto-mechanic effect of the 
apparatus and the dimensions of its different parts, have made me think 
* There is a great analogy, both with regard to the general arrangement of 
the apparatus and the nature of the motive power, between the electro-mag- 
netic apparatus of M. Botto, and the electrical clock of M. Zamboni, described 
in the Bibl. Univ., t. xlvii. p. 183. (1831). It will be recollected that Zamboni’s 
clock is put in motion by a pendulum, alternately attracted and repelled by the 
poles of two of the dry piles which bear his name.—A. pe ua Rive. 
+ The Chev. Avogrado and the Chev. Bidone, who have successively seen 
the apparatus in motion, did not dissemble the agreeable surprise which they 
experienced, not merely from the novelty of the fact, but also from the reflec- 
tions suggested by the general relations which may connect this simple result 
with the progress of physics and mechanics, 
Z02 
