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19.
League, ye drops of rain wch are formed there are about ye thickness of three lines Dicimeter and aquire their compleat swiftness to make 32 feet in a second after ye descent of 100 feet as is explained in ye end of ye treatise of percussion, every drop by falling from ye hight of ye cloud draws along with it two or three times as much air as it is thick, this is proved by ye experiment of a small ball permitted to fall into a pail of water; for as soon as it, wch canot proceed but from ye air wch follows it to ye bottom of ye vessel, now it is known that ni many places there is made use of certain bellows Ar melt ye minera of iron in ye furnace by ye sole following of water, this is done after ye this manner.  there is a pipe ^[[of]] wood on him of 14 or 15 feet high, and of a foot diameter which is soddered in a moderate tub turnd upside down,, when ye ball is placed upon ye ground so that by ye little water just there falls it stops ye passage and ye air canot any more enter there. there is left at ye top of ye pipe one hole of three or four inches diameter, in wch is put a funnel where ye neck is of ye same thickness and there is made to fall from 15, 20, or 30 feet high ye water of some fountain, whereas its longness is falling is near equal to ye  hole of ye funnel, that water falling draws with it much air wch follows it below ye funnel and to ye bottom of ye tub, wch canot go out again thrô ye funnel becaude of ye weight of ye water, wch continueth to fall, and ye swiftness of its motion; there is put at ye side of ye tub a pipe wch goeth straight to ye hole in ye bottom of ye furnace where it coke ought to blowed and if air puffed and inclosed in ye tub not being able to go out ye top because of ye air violent fall of ye water wch fill up ye hole of ye funnell not thrô ye bottom because of ye water wch is there collected, and wch is elevated a foot or two above ye chinks wch remain between ye earth at ye bottom and ye staves of ye tub, it is constrained to go out with a very great force thrô ye end of ye channel, so that is produceth ye same effect in blowing ye coakes as great bellows of leather ought it used elswhere.  It ought therefore to happen wch fall from ye cloud in gross drops and in great abundance, will draw with it much of ye air as hath been proved, that air canot [[strikethrough]]also ?[[/strikethrough]] remount when it is near ye earth because of ye other drops wch fall with violence; it canot also extend it self towards ye back side of ye cloud, because if ye sustained by y great wind wch drives it, now yet by ye sides or tub very little, because if ye same wind [[?presseth]] ye cloud by ye two sides; it remains therefore that all its strength be made before Ye rain, and that this [[?]] joyned to that of ye wind wch carrys ye cloud should be about twice as swift as ye wind wch pusheth it, and that this augmented make more than 60 feet in a second then it may overturn trees as is proved hereafter.  it canot preceede ye rain above three or four hundred paces ordinarily, for ye reason that hat been said, that a space of air of such swiftness as it should be moved, canot continue its motion on a good distance in a straight line, if a thick cloud from whence their fell rain; for in that side from whence ye wind came ye drops did fall almost always streight; but in ye middle and near ye foremost drops, they made angle of more than 25° degrees as in ye figure following, in which A B is ye cloud B D ye cost from whence came ye wind, and  G H ye drops most forward.

[[image: drawing of a heavy dark cloud and rain.  Left edge of cloud labeled A; right edge B; rain drops (dotted lines) falling from right side of cloud fall straight down; gradually falling angled to about 75° relative to ground toward left end of cloud.  Raindrops are labeled G at cloud level; and H at the ground]]

Transcription Notes:
Dicimeter: one-tenth of a meter. "Canot" is written with a macron (bar) over the single "n" not sure how to transcribe.