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It happens sometimes that when a great wind meets sideways another weaker, let it be  opposite or not, it carrys ye wch is near it and makes it to turn round with great swiftness, and [[strikethrough]] makes [[/strikethrough]] that turning of ye air wch is called a whirlwind goeth forward with ye stronger wind, and carry away all that wch it wraps up that hath not much weight; as dust, feathers and whole haycocks wch will sometimes fall above a quarter of a league distant. These whirlewinds also sometimes carry away a great quantity of water out of ye sea, wch appears to those which see it at a distance as a great pillar of water

There is seen an example of these winds wch blow at ye side both contrary in certain chimnys when there is made a great fire ye door remaining shut: for ye rarified air and ye flame wch are elevated make one part of ye air of ye chamber to follow, and that wch remains benig too much dilated by that means, it ought necessary to return from ye top to ye bottom thrô ye chimny, wch brings back a part of ye smoak, and spreads it self thrô ye chamber, and ordinaryly the smoak and ye rarefied air mount on one side and ye heavy descend by ye other with one part of ye smoak, this may be avoided by leaving ye door or a window half open: for ye air wch enters there follows ye motion of ye smoak thrô ye chimny, and sufficiently fills ye chamber. and if there was only a hole of an inch diameter in ye window or in ye door to permit ye air from with out to enter, there would be a sufficient wind to extinguish ye candles that should be exposed to it.

When ye wind meets with an obstacle a great wall it changeth its direction as is represed beyond that obstacle, as may be seen in this figure in wch A B represents ye wall and ye Lines CA, CH, IL, FB, ye direction of ye wind benig free. now it is evident that ye

[[Note: the original author meant "GH" but wrote "CH" here.]]

[[drawing of a wall; what appears to be a chimney (or kiln stack) part of and on the left side of the wall (R); and a structure (house?) (F) built up against the right side of the wall;  and layers of wind drawn blowing over top of the structure (N M, E, D).  At several levels of the wall there are horizontal lines labeled, top to bottom, as follows: A C, H G, L I, B F.]]

air is put into a spring between A and B, and that it cannot be extended towards ye base, it extends it self from ye side CA to DE, and ye air wch is towards R having little motion that wch is in [[N]]M, is pulled thither by that wch is higher than M in N as is seen to happen to water beyond ye piles of bridges where it is very rapid

From thence it follows that it on ye side ye wind comes there is a wall higher than a chimny, ye smoak difficultly goeth out, because that ye wind turneth into a wirlewind after it hath passed ye wall, and enters with force in ye chimny. And althô ye wall should be even with ye chimny and a small distance from it, it would cause almost a like effect, as may be judged by ye figure following, in wch A B maketh ye direction of ye wind B C is ye wall opposite to that direction, D E are two stack of chimnys of ye same hight with ye wall. Ye wind 

Transcription Notes:
Reviewed - Uses "the" on this page, but has been using "ye." Is that normal? Illustration: http://echo.mpiwg-berlin.mpg.de/ECHOdocuView?url=/permanent/library/QERNH1MN/pageimg&start=11&mode=imagepath&pn=94&ww=0.1642&wh=0.2457&wx=0.7905&wy=0.0454