314 Description of the model of an Electro-Magnetic Engine. 
two shaped like a T. These holes are connected by pieces of cop- 
per, which form their bottom, being made into tight cups by sealing 
wax. ‘These pieces of copper cross at the center, and are kept from 
touching each other by silk, and thus connect those holes which are 
diagonally opposite. S,S, are two pieces of copper which are fixed 
upon an axis in such a manner as to allow the extremities to dip 
alternately in the two pair of holes, which are filled with mercury. 
T, is a spring of wire, which by means of a crank fastened to the 
axis of the two strips of copper $8, 8, brings them down to the cups 
of mercury either way whenever the crank has passed the perpen- 
dicular. U, V, are two strips of zinc soldered to the center of S, 
S, and which are connected with the poles of a galvanic battery. 
W, is a lever fastened to the extremity of the axis, and which moves 
it together with the strips S, S. The extremities of the ribbons J, 
K, L, M, are inserted in the cups of mercury R, R, one from each 
magnet being inserted in each cup, and the arrangement being such 
that the upper poles of the temporary magnets shall both be of the 
same name. The lever W, is moved by the pins 1, 2, of the rod 
O, thus continually reversing the currents of electricity as they flow 
through the ribbons J K, LM, of the two galvanic magnets, and in 
this way changing the poles of these magnets. 
Let us then suppose the end A of the magnet A B, to represent 
the north pole, and the pole C of the magnet C E D, alsoa 
north pole, while the arrangement is such that F is the north pole 
also of the magnet F HG. The ends J, K, L, M, being properly 
arranged in the two cups R, R, and the lever W, being placed be- 
tween the pins 1, 2, of the rod O, upon connecting the zinc ribbons 
V,U, with the poles of a calorimotor the horse shoe magnets be- 
come instantly active, and the north pole A is repelled from the 
north pole C, while the south pole B is attracted towards the north 
pole F. The pin 2, by being raised, at length raises the lever W, 
and the strips S, S, are brought by the spring T to the cups Q, Q; 
when the currents in the zinc ribbons around the temporary magnets 
are instantly reversed, and the two lower poles converted into north 
poles. The north pole A is then instantly repelled from the north 
pole D, and the south pole B from the south pole F, until the pin l 
depresses the lever W, when the currents being again reversed the 
ppeeae is in the same state as at the first. In this way a constant 
: motion is kept up. The model of this size works well, 
and. with considerable power. 
