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Show 4:92 On tie Ujé quointedflomfufiam in [M. P.] flouting Building:from Lightning. 493 is placed* to the part immediately over the large OMrmz‘z'oIz. body, and there accumulated ready to (hike into it explain this, it is fuppofed that the cotto n "S conneétion With the prime conductor recez b y from with itswhole undiminifhed force, as foon as within the {hiking dif'cance ; and, were the prime con- ductor moveable like a cloud, it would approach ' To .It a quantity of its electricity; which OIVCS fions'lts being attraéted by thefinger that re C93- the body by attraction till within that dif'rance. The fwift motion of clouds, as driven by the winds, probably prevents this happening f0 often asother- ?till 1n nearly its natural Rate. But when amal' nS 15 oppofed to the cotton, its electricity is thig h" taken from it, falter than it can at a diftance by wife it might do; for, though parts of the cloud A may floop towards a building as they pafs, in con- fupplled with a frefh quantity from the cbndué‘to '6 :I‘herefore being reduced fled/"87‘ to the natural Rate. it is attracted up to the electrified prime conductor ' flfequence of fuch attraétion, yet they are carried forward beyond the {triking dif'tance before they could by their defcending come within it. raider tlum down, as before, to the finger. ' Suppofing farther that the prime conduétorre- prefents a cloud charged with the cleétric fluid the cotton, 21 ragged fragment of cloud (of which; EXPERIMENT V. Attach afmall light lock ofcotton to the underfide of the prime conductor, f0 that it may hang down towards the pointed wire mentioned in the ,firft experiment. Cover the pointwith your finger, and the globe being turned, the cotton will extend itfelf, firetching down towards the finger as at a; but on uncovering the point, it int‘cantly flies up to the prime conductor, as at I), and continues there as. long as the point is uncovered. The moment. you cover it again, the cotton flies down again, extending itfelf towards the finger ;. and the fame happens in degree, if (infiead of the finger) you uiehuncovered, the [dam end of the wire uppermo . the underfide of great thunder clouds are fee-n to ‘IlllllllllllllllIlllNMlV have many;) the finger, a chimney or hiOhefL part ofa building-VVC then may conceiveothat ‘ Him when fuch a cloud pafl‘es over a Mia/Mgr, tome one of its ragged under-hanging fragments may be» drawn down by the chimney or other hiOh partof the edifice; creating thereby a lime to?) com-- mum'mz‘z'm between it and the great cloudy-But a lairg‘poz‘m‘rd rod being pretented to this fragment, may occafion its receding, like the cotton, up to the great Cloud; and thereby [rural/c, iul‘tead g." lq/éfling the dif'tauce, to as often to make it greater than the {triking diltance.--Turning the 612;!" cm! qf a wire uppermol'r, (which rtpreients the unpointed bar) it appears that -h,: Lune good effect is not from that to be e.;pe'ted.-Along pointed ‘ [i. e. drawn for a time, to a different part of the conduétor, b": - netmofit. rod it is therefore imagined, may prewar tome 15.1 Git/cr- Arches |