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 electrified by that discharge.
CORRECTIONS _and_ ADDITIONS
_to the_ PRECEDING PAPERS.
Page 2, Sect. 1. We since find, that the fire in the bottle is not
contained in the non-electric, but _in the glass_. All that is after said
of the _top_ and _bottom_ of the bottle, is true of the _inside_ and
_outside_ surfaces, and should have been so expressed. _See Sect._ 16, p.
16.
Page 6, Line 13. The equilibrium will soon be restored _but silently_, etc.
This must have been a mistake. When the bottle is full charged, the crooked
wire cannot well be brought to touch the top and bottom so quick, but that
there will be a loud spark; unless the points be sharp, without loops.
Ibid. line ult. _Outside_: add, such moisture continuing up to the cork or
wire.
Page 12, line 14. _By candle-light_ etc. From some observations since made,
I am inclined to think, that it is not the light, but the smoke or
non-electric effluvia from the candle, coal, and red-hot iron, that carry
off the electrical fire, being first attracted and then repelled.
Page 13, line 15. _Windmil wheels_, &c. We afterwards discovered, that the
afflux or efflux of the electrical fire, was not the cause of the motions
of those wheels, but various circumstances of attraction and repulsion.
Page 16, line 21. _Let_ A _and_ B _stand on wax_, &c. We soon found that it
was only necessary for one of them to stand on wax.
Page 19. in the title r. _on_.
Page 24, line 12. r. contact, line 24. confined.
Page 25, line 10. for _stand_ r. _hand_.
Page 28, line 2. _The consequence might perhaps be fatal_, &c. We have
found it fatal to small animals, but 'tis not strong enough to kill large
ones. The biggest we have killed is a hen.
Page 31, line 20. _Ringing of chimes_, &c. This is since done.
Page 33, line 22. _Fails after ten or twelve experiments._ This was by a
small bottle. And since found to fail after with a large glass.
Page 40, sect. 50, 51. _Spirits must be heated before we can fire them_,
&c. We have since fired spirits without heating, when the weather is warm.
_FINIS._
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FOOTNOTES.
[1] We suppose every particle of sand, moisture, or smoke, being first
attracted and then repelled, carries off with it a portion of the
electrical fire; but that the same still subsists in those particles,
till they communicate it to something else; and that it is never
really destroyed.--So when water is thrown on common fire, we do not
imagine the element is thereby destroyed or annihilated, but only
dispersed, each particle of water carrying off in vapour its portion
of the fire, which it had attracted and attached to itself.
[2] Our tubes are made here of green glass, 27 or 30 inches long, as big
as can be grasped. Electricity is so much in vogue, that above one
hundred of them have been sold within these four months past.
[3] To charge a bottle commodiously through the coating, place it on a
glass stand; form a communication from the prime conductor to the
coating, and another from the hook to the wall or floor. When it is
charged, remove the latter communication before you take hold of the
bottle, otherwise great part of the fire will escape by it.
[4] The river that washes one side of _Philadelphia_, as the _Delaware_
does the other; both are ornamented with the summer habitations, of
the citizens, and the agreeable mansions of the principal people of
this colony.
[5] An electrified bumper, is a small thin glass tumbler, near filled with
wine, and electrified as the bottle. This when brought to the lips
gives a shock, if the party be close shaved, and does not breathe on
the liquor.
[6] Thunder-gusts are sudden storms of thunder and lightning, which are
frequently of short duration, but sometimes produce mischievous
effects.
[7] See the ingenious essays on electricity in the Transactions, by Mr
Ellicot.
[8] See the first sixteen Sections of my former Paper, called _Farther
Experiments_, &c.
[9] See § 10 of _Farther Experiments_, &c.
[10] In the dark the electrical fluid may be seen on the cushion in two
semi-circles or half-moons, one on the fore part, the other on the
back part of the cushion, just where the globe and cushion separate.
In the fore crescent the fire is passing out of the cushion into the
glass; in the other it is leaving the glass, and returning into the
back part of the cushion. When the prime conductor is apply'd to take
it off the glass, the back crescent disappears.
[11] Gilt paper, with the gilt face next the glass, does well.
[12] See farther experiments, § 15.