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60.

in C it will continue its direction below C D, as in G H and by consequence will go swifter in G and H than in I and D, and from hences proceeds that in moderate rivers there is always great holes a little below ye bridges;  it is seen by experience in ye bridges of ye Cansy of Nogent upon ye Seine:  For ye water wch is elevated by incountering ye piles of ye bridge takes a greater swiftness and passeth with violence below from ye top to ye bottom where it carrys ye sand and  and draws its a little lower where it is heaped up:  But when ye water is in its bed and in its ordinary course and moderate, ye superior ought to go swifter than that wch is a foot below for let A B be an horizontall line and C D ye steep place of ye bottom of ye river, D E ye water wch is half a foot from ye uppermost F G, both parrallel to C B now because ye water is viscouse and its continuous parts are a little joyned together, ye water D E will carry that wch is immediately above with near ye same swiftness;  and follows that wch is in C F G, wch is moved as well as it because of its steep place, goeth somewhat further than ye water B E, wch one may ye better comprehend if we suppose F L a board swimming upon ye water, and that ye upper side may be a little steep parallel to C B, having a very sound ball at ye upper side;  for that peice of wood carried by ye water, would carry ye ball, wch would [[?roul]] itself also along ye board to G, and by consequence its swiftness would be greater than that of ye board.

[[image:  Diagram of four lines - straight horizontal line labeled A B; a line making an approximately 10 degree line labeled C connecting to point B; two lines above and paralles to C B labeled D E and F G;  and a rectangle (plank) labeled L]]

I have more oftentimes observed ye herbs wch ye water would carry away, and I did see manifestly that those wch were between two waters near ye bottom more advanced than those wch were at ye surface, were soon passed and left behind by ye superiors, and if I should cast into ye same river an hand full of gross sawdust of wood wch would go to ye bottom, I should always see ye superiors precede ye others in proportion as they were more or less distance from ye bottom;  by wch experiment it appears that in rivers wch run freely, ye upper water goeth swifter than that of ye midle, and that of ye midle swifter than that wch is near ye bottom, and that in those wch are constrained to pass thrô a narrow bed, being retained on both sides, that of ye middle goeth swifter than that of ye surface if it is but 3 or 4 foot deep.

     This is the way to calculate ye force of ye mill wheels at ye Seine.
  
  I suppose there is two wheels to one axis that they have 5 feet semi diameter, and that ye boards (wch is called anbes) wch serve for shovels are two feet heigh in ye water and 5 feet long:  I suppose also that ye swiftness of ye water wch stricks ye shovels is 4 feet in one second, wch is ordinary;  for it is elevated a little by ye incounter of ye post wch carrys ye wheel, and by consequence goeth over against ye middle of ye post swifter than if it had not been stopped:  Now as it hath been said above a reservatory of 12 feet heigh spouting below 12 feet a square spout of 1/2 foot large, can sustain 210 pound;  its swiftness wch is 24 feet in a second is 6 times as great as that wch strikes ye mill wheels:  Therefore that water wch strikes a shovel of half a foot ought to sustain but ye 35th part of 210 pounds, by ye first rule;  therefore it will sustain 5 5/6 pounds. Ye square foot will sustain ye quadruple, viz 23 1/3 pounds and because ye shovels of a wheel have 10 superficiall feet they support 233 1/3 pounds, ye other wheel will have ye same force:  Therefore both will sustain 466 2/3 pound put in a horizontal rule at ye same distance of ye axis, as ye midle of ye shovels of 4 feet.

    The force of ye shoc of wind against ye sayls of a windmill is found in this sort.

    Take a cylinder turnpike like to that spoken of in ye foregoing experiments;  A B in that figure represents it axe, G H is an horizontall rule wch crosseth ye axe of ye cylinder at right angles, I L is another rule placed perpendicularly upon G H, M N O P is yet a perpendicular rule placed obliquely at an angle of 45 degrees in respect of ye rule G R:  Now if we suppose a spout of water wch strikes directly ye rule I L towards ye point R and wch turneth ye cylinder according to ye order of ye letters A B C D, it will act with all its force to sustain ye weight R:  But if another equal spout of water strikes directly ye rule M O at ye point S wch is supposed as far distant from ye 

Transcription Notes:
mandc: "Herbs" translated as "weeds" in the Desaguliers translation. Waterwheel "boards" in the Desaquileir translation uses the English terms ladles, floats or pallets. Could find to French word "anbes." Image: http://echo.mpiwg-berlin.mpg.de/ECHOdocuView?url=%2Fpermanent%2Flibrary%2FQERNH1MN%2Fpageimg&start=11&viewMode=image&mode=imagepath&pn=211&ww=0.1993&wh=0.2736&wx=0.6203&wy=0.0423