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Show [M. P.] flowing Buildingsfiom Lightning. 489 488 071 27):? U]? qf pointed Condufior: z'rt peéted to difcharge from the clouds filently in a {hort time, is yet unknown; butl have reafon apparent quantity thus difcharged, I, cannot but conceive that a numéer * of fuch conductors mull; conlideruhly lvfl‘en that of am approaching cloud, from a particular no to think it may at fome times belore it comes to near as to deliver its contents in be very great-In Philadelphia I had {uch a rod fixed to the top of my chimney, and extending about nine feet above it. From the foot of this a general llroke‘.---An effect not to be expee‘ted from bars unpainted; if the above experiment with rod, 3 wire (the thieknefs ofa goofe quill) came the cafe. through a covered glats tube in the roof, and down through the well of the {lair-cafe; the lower end connected with the iron {pear of a pump. On EXPERIMENT II. The pointed wire .under the primeconduétor continuing~ of the fame height, pier/5 it between the thumb and finger near the top, {0 asjzyi [a cancm/ the point; then turning the globe, the elec~ trometer will rife and mark the full charge. Sli the fingers down f0 as to difcover about half an inch ofthe wire, then another halfinch, and then the flair-cafe oppofite to my chamber-door, the wire was divided; the ends teparated about fix inches, 2 little bell on each end; [and] between the bells a little brats ball {ufpcnded by a fill: thread, to play between and firike the bells when clouds pulled with electricity in them. After having frequently drawn fpirks and charged bottles from the bell of the upper wire, I was one night waked by loud cracks on the (lair-cale. Starting up and opening the door, I perceived that the brats ball, infiead of vibrating as ufual between the bells, was repelled and kept at adif'tance from both; while the fire pulled fometimes in very large. quick cracks from bell to bell; and fumetimes in acontinued denfe white ttream, teemingly as large as my finger, whereby the whole flaircafe was enlightened as with funfhine, {0 that one might fee to pick up a pin *. And from the ' Mr. De Romas fmv dill-greater quantities oflightning brought down by the wire of his kite. He had " cxplofions from it, the nmfe " of whiCh greatly refembled that ofthunder, and were heard (from " without) into the heart of the city, notwithflanding the vanous " noifes them-The fire feen at the inltant of the cxplolion had the {‘ we a the blunt end of the wire is deemed pertinent to another; at every one of thefe motions dycoverzhg more and more of the pointed wire; you will fee the eleétrometer fall quick and proportionably, {topping when you ftop. If you flip down the whole dfiance at once, the ball falls infiantly down to the Item. OMr'vzztz'm. From this experiment it feems thata greater efi'eét in drawing of? the lightning from the clouds may be expected from long pointed rods, than " lhape of a fpindle eight inches long and five lines in diameter.- " Yet from the time of the explofion to the end of the expenment, " no lightning was feen above, nor any thunder heard-At another " time the fireams of fire iffuing from it were obferved to be an inch " thick and ten feet]ong."---Su Dr. Prigfllqy': Hifloty nf Eltflriao', pages 354-6154} edition. _ 2 Twelve were prepared on and near themagazines at Purfleet. Rtr from ‘llllllll.lIllli\lIlllWW\l -l man 5 Milk |