hey might
have been carried from the side in this way or downwards, but not to bodies
above them; or the attraction and apprehension of contiguous bodies would
have been momentary only. But with a single friction jet and amber draw and
attract bodies to them strongly and for a long time, sometimes for the
twelfth part of an hour, especially in clear weather. But if the mass of
amber be rather large, and the surface polished, it attracts without
friction. Flint is rubbed and emits by attrition an inflammable matter that
turns into sparks and heat. Therefore the denser effluvia of flint
producing fire are very far different from electrical effluvia, which on
account of their extreme attenuation do not take fire, nor are fit material
for flame. Those effluvia are not of the nature of breath, for when emitted
they do not propel anything, but are exhaled without sensible resistance
and touch bodies. They are highly attenuated humours much more subtile than
the ambient air; and in order that they may occur, bodies are required
produced from humour and concreted with a considerable degree of hardness.
Non-electrick bodies are not resolved into humid effluvia, and those
effluvia mix with the common and general effluvia of the earth, and are not
peculiar. Also besides the attraction of bodies, they retain them longer.
It is probable therefore that amber does exhale something peculiar to *
itself, which allures bodies themselves, not the intermediate air. Indeed
it plainly does draw the body itself in the case of a spherical drop of
water standing on a dry surface; for a piece of amber applied to it at a
suitable distance pulls the nearest parts out of their position and draws
it up into a cone; otherwise, if it were * drawn by means of the air
rushing along, the whole drop would have moved. That it does not attract
the air is thus demonstrated: take a very thin wax candle, which makes a
very small and clear flame; bring up to this, within two digits or any
convenient distance, a piece of amber or jet, a broad flat piece, well
prepared * and skilfully rubbed, such a piece of amber as would attract
bodies far and wide, yet it does not disturb the flame; which of necessity
would have occurred, if the air was disturbed, for the flame would have
followed the current of air. As far as the effluvia are sent out, so far it
allures; but as a body approaches, its motion is accelerated, stronger
forces drawing it; as also in the case of magne