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65.
pound they would sustain 450 times 3 that is to say 337 pound near wch 4 is a number much less than 1152; let it be therefore as 337 to 1152 so 144 ye square of 12 is to 47237 whereof ye square root is 22 1/4 near, there is need therefore of a wind wch goeth 22 1/4 feet in a second to break such a branch of a tree

 The shoc of wind against ye sayls of vessels to make them lean or overturn them follows ye same rules and that of ye equilibrium; for if we put up on ye vessel A B C whose center of gravity is in line B D, awright, at ye point C will make it lean, and ye common center of gravity shall be in ye line B D, wch in ye water shall make an equilibrium to it self and ye weight C to ye rest of ye vessel E F wch shall be on ye other side above the water; now ye sayls being stroke makes ye same effect as a great weight, and we may compare efforts as above, according as ye wind shall be great and ye sayl elevated above ye vessel; and observing ye manner above explained, we may know what swiftness of wind can overturn ye vessel and of that wch is in it, ye greatness of its sayls, ye obliquity of ye direction of ye shoc comparing its force to that of a weight as C; but we might consider that ye vessel doth now turn with ye wind as if it had [[?(essier)]] [[space]] at ye point B wch might turn upon 2 movable pivots and that it is not overturned so easily as it should do; but also in rouling it may take a continuation of motion wch being joyned to a great and suddain puff of wind it may go much beyond ye equilibrium and overturn it;

  When we have a certain quantity of water to employ in a shoc, we may augment its force by setting it fall from a great height.

[[image: drawing of a wooden sailboat with rudder (left) labeled "A", pitched forward with mast at 60° angle with sail raised, the bow dipping downward labeled with an encircled "C (maybe a weight attached to the bow).  Dotted line runs down the mast to a point on the keel labeled "B."  Transcribed on the hull is an X & Y axis, X about the waterline is labeled "E" on left and terminates at the encircled "C" (weight) at the bow.  The Y axis is labeled D at the top and b at the bottom]]

Transcription Notes:
mandc: I described the image first before tackling the text to familiarize with the coordinates. Meaning still elusive. "Essier" may mean "Axis" but the blank left for translation never got filled in. image from Desaguliers: http://echo.mpiwg-berlin.mpg.de/ECHOdocuView?url=%2Fpermanent%2Flibrary%2FQERNH1MN%2Fpageimg&start=11&mode=imagepath&pn=211&ww=0.193&wh=0.2323&wx=0.4706&wy=0.3204