388 Connexion between Magnetism and Electricity. 
N S a wire of iron wiecned, ransvorsely se it the latter be- 
comes permanently magnetic.—Sir H. 
3. If we suppose a oe papas wire parallel to, 
and similarly situated nih, the first, as in this figure, those 
wires will attract each other; but if one conjunctive wire be 
traversed by the electric fluid in one direction, and another 
in an opposite direction, as in the following wood-cut, those 
re. ain 
INE Big 
wires will repel each other. In this circumstance, the dis- 
similarity of the electro-magnetic and of simple electric 
phenomena is observed: for bodies similarly electrified re- 
pel eac r, and, dissimilarly electrified, attract each 
eaiere ; but here the horizontal wires, s similarly electro-mag- 
netized, attract; and, seme electro-magnetized, re- 
pel each other —M. Amp 
4. The shock of a Leyden jar, or battery, passed through 
a wire, confers upon it, at the moment of its passage, prop- 
erties precisely similar to those of the Voltaic apparatus. 
fey peer a steel bar magnetic, it is not necessary that 
it should touch the oan unctive wire, to which it is attached. 
at right angles, for the electro-magnetic influence is convey- 
to some distance, and is not excluded by the interposi-. 
tion of a ie of glass, of metal, or of water.—Sir H. Davy. . 
. The phenomena, exhibited by the electro-magnetic 
or conjunctive wire, may be explained upon the supposition 
of an electro-magnetic current passing round the axis of 
conjunctive wire, its direction aegis upon that of 
the electric current, or upon the poles of the battery with 
which it is connected.—Dr. Wotuaston. 
