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By these it should [seem] as if trial wire required to be drawn out 9 less with the wires at 36 inches distance than with single wire, and 17 less with two wires at 18 inches, whence I should suppose that [the quantity of] el[ectricity] in these three cases was as 96, 87 and 79.

The trial wire not drawn out was 70 inches, but the straight part of it was only 51.

448] Wires of half that length tried in the same manner with a shorter trial wire.

Two wires 1 thick, 24 long, at 18 inches distance.

Trial wire drawn out 1 inch

3

5

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12

14

The same at 36 inches distance.

sep. neg.
very little.

rather doubtful.

did not.

did not.

sep. pos. very little.

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Wire 48 inches long, touched by end of touching wire.

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449] From these experiments the quantity of electricity in

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450] Experiments to determine whether the quant. el. in the large circle was the same whether it was supported on waxed glass* or on silk strings, the trial plates, which were of wood covered with tinfoil being supported on waxed glass, the large trial plate drawn out to n inches being expressed by L-n, the small ditto by S - n.

Large circle supported on silk strings.

L-5 sep. pos. very sensibly if I staid some time before letting down the wires, but scarce sensibly if I did not.

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4 seemed to separate, but rather doubtful if I staid, but not if I did

not.

S-5 sep. neg. if I did not stay, but not if I did.

L 5 tried again, sep. very little whether I staid or not.

The circle supported on waxed glass.

L-5 sep. very little whether I staid or not.
S-5 sep. very little whether I staid or not.

From these experiments there seems no reason to think that there is any sensible difference in the quantity of electricity whether the circle is supported on silk or on waxed glass. I believe the air was moderately but not very dry when these experiments were tried. The next experiment was made the same night.

451] Experiment to determine whether quantity of electricity in coated glass bears the same proportion to that in a non-electric body whether electrification is strong or weak t.

Two pair of corks were made; each separated with rather a less degree of electrification than those used in former experiments. Some lead was then added to those of one pair, so as to double their weight

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and consequently to make them require 2 the force to make them separate.

The plate of glass used was the double plate called A in the following experiments, but with coating 1.78 inches diameter.

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If these experiments could be depended on as perfectly exact the coated plate should contain th part more electricity in proportion when electrified with heavy corks than with light, but this difference is much too small to be depended on.

452] Comparison of two tin circles* 9.3 inches diameter with one of 18.5, the tin plates supported on waxed glass and touched in the same manner as wires, the trial plates supported on silk strings.

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Small plates at 36 inches distance tried again.

sep. very little with L 1, which is the same as before.

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453] A brass wiret, 72 inches long and 19 thick was then tried, touched by middle of touching wire.

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454] From these experiments it should seem as if el[ectricity] in

Large circle touched at extremity

14.63

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If the two circles were placed at the same distance from each other in the same manner as in coated plates, and were electrified by wires touching their centers perpendicularly, the quantity of electricity should

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The quantity of] el[ectricity] in the wire 72 inches long and 19 thick seems to be nearly equal to that in the circle of 18.5 inches. Therefore if we suppose quantity of electricity in a cylinder to be proportional to its length divided by the logarithm

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linder is to

that in globe 4761 to tab. log.. -or as 1.096 to N log. whose diame

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and the quantity of electricity therein is to that in a circle of the same diameter as

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455] A trial plate for Leyden vials consisting of two plates with rosin between.

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456] Therefore the quant. el. in these bodies seems as follows:

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Diameter of the globe 121, therefore quantity of electricity in globe is to Do in circle of same diameter as 1.56 to 1*.

457] Two trial plates were made on a piece of the large bit of ground glass, one 2.37 inches diameter on place where the thickness = 1.80, computed power 31.2; the other 2.57 inches diameter where thickness 1.90, computed power = 34.8.

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The first is called S the other L.

+The plates of ground glass E and F were each coated on one side with a circle 7.95 inches diameter communicating with coating on the other side. These plates were kept from touching by three bits of sealing-wax. When the coatings were kept at distance 39 from each other this is called plate of air 39 thick, &c.

A piece of wire of the same thickness as the other was made to slide thereon.

When the plate of air was tried against trial-plate S with wire drawn out 12 inches it is expressed

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