1030 Dr. Inge n h o u s z’s Experiments 
It is true, that Father beccaria had a long while ago 
-excited an elefitricity, almoft perpetual, by two panes of 
glafs, one placed upon the other, each having but one 
metal coating, and joined together fo that no metal was 
placed between the two glaffes. Thefe two glaffes being 
applied to a prime conductor of an electrical machine, fo 
as to receive a charge in the fame way as one glafs coated 
on both tides is to be charged, afford numberlefs fparks 
from both coatings, after the two glaffes have been dis- 
charged in the common way, by making a communica- 
tion between the two coatings. 
In order to produce thefe fparks, the two glaffes mult 
be feparated from one another, fo as to avoid touching 
the coatings in the moment of reparation . Each of the 
coatings will give a fpark, which may be repeated after 
having replaced the two glaffes one upon another. After 
the two glaffes have been thus joined again, and touched 
after their conjunction, another fpark is obtained from 
both after their reparation ; and thefe fparks may be thus 
repeated almoft ad infinitum', fo that thefe two glaffes, 
once excited, feem to be an unexhaufted fource of elec- 
trical fparks. Father beccaria calls this experiment 
eleBricitas vindex. Whether this denomination be a pro- 
per one to convey fome idea of what is underftood by it, 
I will not now undertake to determine. 
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