[ 7 6 7 ] 
would alfo do, if artificially eledtrifed. The Pro- 
feflor always obferved a greater afcent of the thread 
from artificial electricity than from that from the at- 
mofphere. By the former, he had feen it upon the 
quadrant defcribe an angle of above fifty-five de- 
grees, but never above thirty by the latter. In the 
year 1752, Aug. 9. the apparatus acquired fo great 
a degree of eledtricity from the atmofphere, that 
from the end of the rod the eledtrical flafhes might 
be heard at feveral feet diftance. Under thefe cir- 
cumflances, if any one touched the apparatus, they 
felt a fharp ftroke in their hand and arm. 
ProfefTor Richman fometimes added to this appa- 
ratus a glafs bottle of water, after the manner of 
ProfefTor Mufchenbroek H /, adapted to a veffel of 
metal I K> which was placed upon glafs. The wire 
from the mouth of the bottle of water H L, during 
the time of the thunder, he caufed to communicate 
with B C . From this addition he found the elec- 
tricity from the atmofphere more vehement than it 
was without it. This he firft obferved on May 3 1 , 
w ^ en the eledtrical fire exploded with fuch a 
force, that it might be heard at the diftance of three 
rooms from the apparatus. On the left hand of the 
bottle was placed a fecond eledtrical gnomon *. 
When this was made ufe of, the wire of metal B C, 
and .the wire H L, were connedted with MB L, a 
prime-condudtor from an apparatus for artificial elec- 
tricity jm. a glafs globe, At the fame time alfo, 
from the chain A B was fattened a piece of wire 
B K f which was in contact with the veffel I K. By 
thefe means, when the eledtrical machine was put in 
* See the figure. 
motion, 
