tors
for this purpose; whence many of the phenomena of the torpedo or
gymnotus, and of Galvanism. Thus after having discharged a coated
jar, if the communicating wire has been quickly withdrawn, a second
small shock may be taken after the principal discharge, and this
repeatedly two or three times.

Hence the charge of the Galvanic pile being very minute in quantity or
intensity, will not readily pass through the dry cuticle of the hands,
though it so easily passes through animal flesh or nerves, as this
combination of charcoal with water seems to constitute the most
perfect conductor yet known.

9. As light is reflected from the surface of a mirror before it
actually touches it, and as drops of water are repelled from cabbage
leaves without touching them, and as oil lies on water without
touching it, and also as a fine needle may be made to lie on water
without touching it, as shown by Mr. Melville in the Literary Essays
of Edinburgh; there is reason to believe, that the vitreous and
resinous electric ethers are repelled by, or will not pass through,
the surfaces of glass or resin, to which they are applied. But though
neither of these electric ethers passes through the surfaces of glass
or resin, yet their attractive or repulsive powers pass through them:
as the attractive or repulsive power of the magnet to iron passes
through the atmosphere, and all other bodies which exist between them.
So an insulated cork-ball, when electrised either with vitreous or
resinous ether, repels another insulated cork-ball electrised with the
same kind of ether, through half an inch of common air, though these
electric atmospheres do not unite.

Whence it may be concluded, that the general attractive and repulsive
ethers accompany the electric ethers as well as they accompany all
other bodies; and that the electric ethers do not themselves attract
or repel through glass or resin, as they cannot pass through them, but
strongly attract each other when they come into contact, rush
together, and produce an explosion of the sudden liberation of heat
and light.

III. _Effect of Metallic Points._

1. When a pointed wire is presented by a person standing on the ground
to an insulated conductor, on which either vitreous or resinous
electricity is accumulated, the accumulated electricity will pass off
at a much greater distance than if a metallic knob be fixed on the
wire and presented in its stead.

2. The same occurs if the metallic