of an inch. Then, when the balls A and B were
_inductric positive_, the discharge was about equal at both intervals.
When, on the other hand, the balls A and B were inductric _negative_, there
was discharge, still at both, but most at _n_, as if the small ball
_negative_ could discharge a little easier than the same ball _positive_.

1498. The small balls and terminations used in these and similar
experiments may very correctly be compared, in their action, to the same
balls and ends when electrified in free air at a much greater distance from
conductors, than they were in those cases from each other. In the first
place, the discharge, even when as a spark, is, according to my view,
determined, and, so to speak, begins at a spot on the surface of the small
ball (1374.), occurring when the intensity there has risen up to a certain
maximum degree (1370.); this determination of discharge at a particular
spot first, being easily traced from the spark into the brush, by
increasing the distance, so as, at last, even to render the time evident
which is necessary for the production of the effect (1436. 1438.). In the
next place, the large balls which I have used might be replaced by larger
balls at a still greater distance, and so, by successive degrees, may be
considered as passing into the sides of the rooms; these being under
general circumstances the inducteous bodies, whilst the small ball rendered
either positive or negative is the inductric body.

1499. But, as has long been recognised, the small ball is only a blunt end,
and, electrically speaking, a point only a small ball; so that when a point
or blunt end is throwing out its brushes into the air, it is acting exactly
as the small balls have acted in the experiments already described, and by
virtue of the same properties and relations.

1500. It may very properly be said with respect to the experiments, that
the large negative ball is as essential to the discharge as the small
positive ball, and also that the large negative ball shows as much
superiority over the large positive ball (which is inefficient in causing a
spark from its opposed small negative ball) as the small positive ball does
over the small negative ball; and probably when we understand the real
cause of the difference, and refer it rather to the condition of the
particles of the dielectric than to the sizes of the conducting balls, we
may find much importance in such an observation. But for the prese