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XII. A Meteorological Journal, principally relating to Atmo- 
fpheric EleSlricity ; kept at Knightlbridge, from the yth of 
May, 1789, to the 8 th of May, 1790. By Mr. John Read; 
communicated by R. H. A. Bennet, Efq. F. R. S. 
Read April 14, 1791. 
A DESCRIPTION of the inftrument for coile£ring atmo- 
fpheric ele&ricity, ufed in the following journal. 
Tab. V. reprefuits the apparatus. AA is a round deal 
rod, 20 feet long, 2 inches diameter at the lower, and one inch 
at the upper end. Into the lower end of it is cemented a folid 
glafs pillar B, 22 inches long; the lower end of the glafs 
Hands in a hole made for it in a pedeftal of wood C, which 
flips on the fore-part of an iron bracket D, which is driven 
into the wall, and fupports the whole. About 13 feet above 
the bracket D, is fixed to the wall a ftrong arm of wood E, 
which holds perpendicularly a ftrong glafs tube F, through 
which the rod is Aided gently upwards, till the glafs pillar B 
may be lowered into the hole made for it in C. It is thus 
fixed, and Hands 12 inches from the wall. The tube F is of 
fufficient width to admit a cafe of cork, which' is fattened in 
the infide of it, at the part where the tube is fuftained by the 
arm of wood E, fo that the rod, when bent by the wind, cannot 
touch the tube or break it. The upper extremity of the rod is 
terminated by feveral (harp-pointed wires G. Two of them are 
Vol. LXXXI. C c of 
