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~ 322 Electrical Phenomena in.certain houses. 
I have proved by direct experiment that electricity is excited by 
the friction of leather upon woolen cloth. For this purpose I 
stood upon an insulating stool, and spreading a small piece of ecar- 
peting upon a table before me, rubbed a piece of leather vigor- 
ously upon it, and then bringing the leather near the cap of a 
Sell leaf electrometer, the leaves were repelled with great vio- 
The electricity of the leather wat» of the resinous kind. 
Teter therefore must necessarily be excited whenever a 
person walks with a shuffling motion across a carpet; but it 
may be thought remarkable that the electricity should be intense 
enough to give a bright ‘spark. In order to produce this effect 
‘there must be a combination of some favorable circumstances. 
The carpet, or at least its upper surface, must be entirely of 
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wool, and of a close texture, in order to Sonniah an abundance of 
electricity. So far.as I have had opportunity to judge, I infer: 
that heavy velvet carpets answer this purpose best. ‘I'wo thick- 
nésses of Ingrain carpeting answer very well. A drugget spread 
upon an Ingrain carpet yields a good supply of the fluid. ‘The 
effect of the increased thickness is obviously to improve the insu- 
lation of the carpet, 
he carpet must be quite dry, and also the floor of the 
room, so that the fluid may not be conveyed aw way as soon as it 
is excited. This will not generally be the case. except in winter, 
and in rooms which are habitually kept. quite ywarm.- The most 
remarkable cases which I have heard of in New York have i 
of close, aa houses, kept ey ‘warm by "farsa, and t 
electricity was most abundant in very cold weather. In Pins: oe 
weather, Gite feeble signs of Bhectiicity are obtained. 
3. The rubber, that is the shoe, must also be dry, like the om 
and it must be rubbed upon the carpet somewhat vigorou Ok 
By skipping once or twice across a room with a a motion 
the feet, a person becomes highly charged, and then bri ¢ 
the knuckle near to any metallic body, particularly it it have goc d 
communication with the earth, a bright spark passes. In almost 
any room which is furnished ‘with a woolen carpet, and is kept 
tolerably warm, a spark may thus be obtained in winter—but in 
some rooms, the insulation is so good and the carpets are so elec- 
trical, that it is impossible to walk across the floor, without excit- 
ing sufficient electricity to give as 
It may be said that in this case thet can be but very little 
friction between the shoe and carpet. But it must be remembered 
that the rubber is applied to the eta? with considerable force, _ 
being aided by the whole bhi i a Be e ts so that a slight 
shuffling of the feet acts with great 
In the London and Edinburgh Philosophical Magazine for Feb- 
ruary, 1839, is given an account of a leather strap connecting on 
drum of a Worsted Mill, which gave sparks two inches in 
