en the machine is not in use, let the metals be removed from the
fluid; and, if not to be soon again used, let them be rinsed with
water, carefully avoiding to wet the wooden bar in which the platina is
set.

_The posts_, with which the conducting-cords are to be connected, are
arranged in a row near the front of the helix-box, and are marked A, B,
C, D. Either two of these posts may be used to obtain a current; and
since they admit of six varying combinations, six different currents are
afforded by the machine, viz: the A B current, the A C current, the A D
current, the B C current, the B D current, and the C D current.
Whichever current is used, it may always be known which of the two posts
employed is the positive and which the negative, by observing the
letters stamped upon their tops. The one whose letter comes first in the
order of the alphabet is positive; the other is negative. Also, the one
standing towards the left hand is positive, and that at the right hand
is negative. _The qualities_ of the several currents are stated in a
descriptive paper on the inside of the lid of the machine, which see. It
will there be found that three of the currents--viz, the A B, the A C
and the A D currents--are _electrolytic_: that is, dissolving by
electric action. These electrolytic currents require to be used--one or
another of them--whenever any chemical action is needed; as, in
decomposing or neutralizing _virus_ in the system, destroying cancers,
reducing glands when chronically enlarged, removing tumors or other
abnormal growths, and in treating old ulcers and chronic irritation of
mucous membranes. The other three, being Faradaic or induction currents,
and having no perceptibly chemical action, are used where only change of
electro-vital polarization is required. These Faradaic currents differ
from each other in respect to being _concentrative_ or _diffusive_ in
their effects, and in their _sensational_ force. B C is concentrative
and delicately sensational. C D is also concentrative, though less so
than B C, and is more strongly sensational. B D is diffusive, and the
most energetically sensational of the three.

POLARIZATION.

It may be proper, in this place, to spend a few words upon electrical
polarization in general.

_Electrical polarity_ may be defined as a characteristic of the electric
or magnetic fluid, by virtue of which its opposite qualities, as those
of _attraction_ and _repulsion_ towards the same obj