r44 Obfervations oh Animal Eleéricity. 
matter naturally contained in the external part of the body, 
is expelled by that accumulated more and more in the interior 
parts, on account of the cold, and which thereby acquires a 
ftronger repulfive power, it is of no weight; fince this power 
would prevent the plate of the condenfer from giving up any of 
its natural electricity to the finger when applied to it. There 
is more reafon, therefore, to affert the latter, viz. that this 
want is only apparent; that is, that the eleétric fluid, which 
the external parts of the body naturally poffefs, is not expelled 
by the effects of cold, but fixed, or fo faft united with the 
parts in which it is contained, that it Iofes all movement, 
and gives no indications of its prefence, This kind of union 
is not uncommon in nature: it takes place in regard to the 
particles of fire, which produce heat; when moift bodies 
evaporate, or when falt is mixed with ice. 
10. Laflitude impedes alfo the pofitive animal eleétricity, or 
changes it into the oppofite. During 16 times that I walked 
backwards and forwards in my apartment, or was otherwife 
employed, the temperature of the weather being 10, 12, 14, 
and more degrees of heat, and no cold wind prevailing at 
the time, I foimid the eleétricity only once weakly +, five 
times o, and ten times—. In 32 experiments, when ftand- 
ing at reft, the electrisity was 30 times 0, and twice weakly +. 
In 27 experiments, while I fat at reft, it was always ftrong- 
ly +3 and in five experiments, while walking at a moderate 
pace, it was perceptibly +. I found the cafe to be the fame 
on my fervant and another young man. 
I will not, however, fay that the electricity, when the body 
is in a ftate of reft, always ceafes, or is changed from pofitive. 
Many times the ftrength of the body is greater than to allow 
of its being exhaulted by fatigue, as I have more than once 
experienced. 
11. By rubbing a part of the body, pofitive cle&tricity is 
not impeded. T he rubbing may be performed with linen 
or woollen. 
12. Sudden, fpeedy, and violent ‘motion can change every 
kind of animal eleétricity into the oppofite. A luminous and 
beautiful appearance was occafioned when I inclined and 
‘taifed my body fuddenly in turns, and threw upwards quickly 
and 
