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cloud having paffed over the place where the bar 
Hood, thofe, that were appointed to obferve it, drew 
near, and attracted from it fparks of fire, perceiving 
the fame kind of commotions as in the common 
electrical experiments. 
M. de Lor, fenfible of the good fuccefs of this ex- 
periment, refolved to repeat it at his houfe in the 
Eftrapade at Paris. He raifed a bar of iron 99 feet 
high, placed upon a cake of refin, two feet fquare, 
and 3 inches thick. On the 18 of May, between 
4 and y in the afternoon, a ftormy cloud having 
paffed over the bar, where it remain'd half an hour, 
he drew fparks from the bar. Thefe fparks were like 
thofe of a gun, when, in the electrical experiments, 
the globe is only rubb'd by the cufhion, and they 
produced the fame noife, the fame fire, and the fame 
crackling. They drew the ftrongeft fparks at the 
diftance of 9 lines, while the rain, mingled with a 
little hail, fell from the cloud, without either thun- 
der or lightning ; this cloud being, according to all 
appearance, only the confequence of a ftorm, which 
happen’d elfewhere. 
From this experiment we conjectur'd, that a bar 
of iron, placed in a high fituation upon an eleCtrical 
body, might attraCt the ftorm, and deprive the cloud 
of all its thunder. I do not doubt but the Royal So- 
ciety has directed fome of its members to purfue thefe 
experiments, and to pufh this analogy yet further. 
I do not know, Sir, whether Mr. Franklin’s letters 
were before your confiderations upon earthquakes : if 
they were, we are oblig’d to Mr. Collinfon for his com- 
munication of Mr. Franklin’s notions $ if they are not, 
you deferve the honour of the difcovery $ and whofe- 
6 foever 
