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SIR, St. Germain, June 2g, 1752. 
Read Nov. 23 /^\ N the 26 of this month we had a 
75 - florm at two different times : the 
firfl was at 3 in the afternoon, and the fecond at half 
an hour after 6. This florm, which came from the 
South-well, was very inconfiderable : there were but 
two or three claps of thunder, either at 3 or at 6 o’ 
clock 5 and there was a confiderable interval between 
the lightning and the clap, which fliew’d, that the thun - 
derwas at a great diflance. Neverthelefs the effects of 
the electricity were very violent, which I attribute to 
M. Le Monnier’s ingenious apparatus ; which is as 
follows : 
It is certain, by M. Mufchenbroek’s experiments, 
that the more Surface the eleCtrifed bars have, the 
commotions are the more violent ; but, as it would be 
difficult to fallen rods or bars of a certain lize to the 
ends of the great wooden poles, M. Le Monnier has 
ingenioully Supplied that defeCt, in forming a maga- 
zine for the electricity. This magazine is only a com- 
munication of the electricity, which defcends from the 
bar of iron, fituated at the top of the pole, with Seve- 
ral other large bars of iron placed near the pole. 
The greater the quantity of thefe bars, the greater is 
the quantity of electricity furnifh'd by the magazine. 
In the lafl experiment we had a tin pipe, of 7 
feet long, and about y inches diameter. It was the 
firfl magazine : the fecond confided of fix great bars 
of iron of fix feet long each, placed in parallel order 
upon glafs bottles. All thefe magazines communi- 
cated with the iron wire, that defcended from the lit- 
tle bar at the top of the great pole, which I defcribed 
in my lafl letter. 
Yy y 2 
The 
