electrical fire from the floor to the cushion; then, if
there be no fine points or hairy threads sticking out from the cushion, or
from the parts of the machine opposite to the cushion, (of which you must
be careful) you can get but a few sparks from the prime conductor, which
are all the cushion will part with.
Hang a phial then on the prime conductor, and it will not charge, tho' you
hold it by the coating.----But
Form a communication by a chain from the coating to the cushion, and the
phial will charge.
For the globe then draws the electrical fire out of the outside surface of
the phial, and forces it, through the prime conductor and wire of the
phial, into the inside surface.
Thus the bottle is charged with its own fire, no other being to be had
while the glass plate is under the cushion.
Hang two cork balls by flaxen threads to the prime conductor; then touch
the coating of the bottle, and they will be electrified and recede from
For just as much fire as you give the coating, so much is discharged
through the wire upon the prime conductor, whence the cork balls receive an
electrical atmosphere. But
Take a wire bent in the form of a C, with a stick of wax fixed to the
outside of the curve, to hold it by; and apply one end of this wire to the
coating, and the other at the same time to the prime conductor, the phial
will be discharged; and if the balls are not electrified before the
discharge, neither will they appear to be so after the discharge, for they
will not repel each other.
Now if the fire discharged from the inside surface of the bottle through
its wire, remained on the prime conductor, the balls would be electrified
and recede from each other.
If the phial really exploded at both ends, and discharged fire from both
coating and wire, the balls would be _more_ electrified and recede
_farther_: for none of the fire can escape, the wax handle preventing.
But if the fire, with which the inside surface is surcharged, be so much
precisely as is wanted by the outside surface, it will pass round through
the wire fixed to the wax handle, restore the equilibrium in the glass, and
make no alteration in the state of the prime conductor.
Accordingly we find, that if the prime conductor be electrified, and the
cork balls in a state of repellency before the bottle is charged, they
continue so afterwards. If not, they are not
* * * * * EXPERIMENTS AND OBSERVATIONS ON ELECTRICITY, MADE AT _Philadelphia_ in _America_, BY Mr.Page 5
a man standing on wax may be electrised a number of times, by repeatedly touching the wire of an electrised bottle (held in the hand of one standing on the floor) he receiving the fire from the wire each time: yet holding it in his own hand, and touching the wire, tho' he draws a strong spark, and is violently shock'd, no Electricity remains in him; the fire only passing thro' him from the upper to the lower part of the bottle.Page 6
_ _SIR_, In my last I informed you that, in pursuing our electrical enquiries, we had observed some particular Phaenomena, which we looked upon to be new, and of which I promised to give you some account, tho' I apprehended they might possibly not be new to you, as so many hands are daily employ'd in electrical experiments on your side the water, some or other of which would probably hit on the same observations.Page 7
Points of wood will do as well as those of iron, provided the wood is not dry; for perfectly dry wood will no more conduct Electricity than sealing wax.Page 8
_ This experiment should be made in a closet where the air is very still.Page 10
--We electrify, upon wax in the dark, a book that has a double line of gold round upon the covers, and then apply a knuckle to the gilding;.Page 12
When we use the terms of _charging_ and _discharging_ the phial, 'tis in compliance with custom, and for want of others more suitable.Page 17
The operator, who holds the picture by the upper-end, where the inside of the frame is not gilt, to prevent its falling, feels nothing of the shock, and may touch the face of the picture without danger, which he pretends is a test of his loyalty.Page 19
--The thimbles are well fixed, and in so exact a circle, that the bullets may pass within a very small distance of each of them.Page 27
If they are much heated a small spark will do; if not, the spark must be greater.Page 31
In the dark you may see a light on the point, when the experiment is made.Page 36
Set the iron punch on the end upon the floor, in such a place as that the scales may pass over it in making their circle: Then electrify one scale by applying the wire of a charged phial to it.Page 40
Were these two points perfectly equal in acuteness, the leaf would take place exactly in the middle space, for its Weight is a trifle, compared to the power acting on it: But it is generally nearest the unelectrified plate, because, when the leaf is offered to the electrified plate at a distance, the sharpest point is commonly first affected and raised towards it; so that point, from its greater acuteness, receiving the fluid faster than its opposite can discharge it at equal distances, it retires from the electrified plate, and draws nearer to the unelectrified plate, till it comes to a distance where the discharge can be exactly equal to the receipt, the latter being lessened, and the former encreased; and there it remains as long as the globe continues to supply fresh electrical matter.Page 42
greatest quantity.Page 43
I feel a want of terms here, and doubt much whether I shall be able to make this part intelligible.Page 45
--Glass, a body extremely elastic (and perhaps its elasticity may be owing in some degree to the subsisting of so great a quantity of this repelling fluid in its pores) must, when rubbed, have its rubbed surface somewhat stretched, or its solid parts drawn a little farther asunder, so that the vacancies in which the electrical fluid resides, become larger, affording room for more of that fluid, which is immediately attracted into it from the cushion or hand rubbing, they being supply'd from the common stock.Page 53