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40.

to root up ye piles E F and G H;  but it ought to take ye proportion of its force but from half the distance A B because that part of ye Ice A B acts not but according to its distance from ye point of support D but it there is as much Ice at ye other side and at ye same length then it will empty its whole effort:  but as ordinarily ye bridges are very heavy they are for ye most part carryed away by ye continnal shoc of great peices of Ice, such by little and little shake them and root them out by knocking against them, than by ye lifting up of ye Ice wch cannot there make a great effort.

If a light body is put into liquors of different specific weight, ye part sunk in ye one shall be to ye part sunck in ye other as ye specific weight of one is to ye specific weight of ye other.

For ye same reason ships and boats loaden with merchandise ought to sink into ye water till ye water whose place they posses below ye level, weights as much as ye vessel and all that wch is in it, whence it happens sometimes that these vessels entering from ye sea into rivers run to ye bottom because that ye fresh water being lighter than that of ye sea, ye space of ye fresh water equal to that of wch ye whole vessel should occupy is less heavy than ye weight of ye vessel, and that in ye sea ye weight of ye vessel is less heavy.

Rule II.

  Bodys lighter than ye water being retained by force at ye bottom of ye water, and being afterwards set at liberty are elevated to ye top of ye water in ye following manner: 

[[image: Drawing of a large vessel A C D B with horizontal dotted line showing filled to level A B.  There is a rectangle (block) E F G H submerged to near the bottom C D.  Two vertical dotted lines K and I descend from the surface to the rectangle points E and F, and then extend on down from points G and H to the bottom of the vessel C D.  There are two marks thru C D labeled L.]]

A B C D is water contained in ye vessel;  E F G H is ye body whose specific weight is less than that of ye water; from ye column K J G H weighs less than a column of water of ye same bigness I H B D and by consequence ye water near ye point H, between H and D is more charged than that wch is between G G and H, and by consequence it will insinuate and run under ye body G H and will push it up.  Ye other parts of ye water such are at ye bottom at ye same depth, as ye bottom of ye body have ye like effect to push it up;  and as it will meet with heigher ye same dispositions it shall be all way elevated till one part be above ye water; and because it is elevated with swiftness, it shall pass a little heigher than ye place where it ought to stop;  but it will redescend a little lower than that place and at last after some other balancings it will be stopped in ye place of its equilibrium according to ye foregoing rules.

  But if there is a hole in ye bottom of vessel as L thro wch ye water may run ye body F H shall not be elevated;  for ye same water wch ought to pass ye body on haigh descends by ye hole and is drawn from ye side by its viscosity;  and being passed by ye upper part of ye column of water K E I F, it will remain always at ye bottom of ye water, till it is wholly run out.

  It is evident by what is said about that if A B C D is a vessel full of water having an hole in E, ye water wch is at ye side as in F being pressed by ye whole superiorr water, shall

[[image: cross section drawing of a vessel outline A C D B, with letters O and G center interior. At the bottom line C D there is a semicircular dotted line centered on two lines through C D at E.  The semicircle is divided into three sections by radians E H and E L, and the sections are labeled Q M and N. There is an F near E. The top of the semicircle is labeled I.  There is another dotted line semicircle on the right wall D B of the vessel attached at points K and S.  Two lines (hole) through D B labeled P. There is an R labeling the semicircle.]]

be pressed toward ye hole with more force than that wch is above perpendicularly;  as in I if ye point G is farther distant from ye point E than ye point F; we may see ye experiment in permitting to fall a small peice of paper twisted and wet, or some other small body a little heavier than ye water as ye fragments of ye sawings at [[?horns]]:  for as soon as ye finger is taken away sch should sustain ye water in E, ye water runing shall follow ye paper in F wch will make to know ye ye parts of ye water near to ye small body;  are there passed after ye same manner as ye other parts wch are nearer ye hole, and wch are compared in ye hemisphere Q H I L N, those wch should be nearest at M or F will go to succeed those wch run swifter than ye farther distant, as H or L and much more than those wch are as in G or heigher as in O.  We may make an experiment by permitting small parcells of some matter to fall into ye water before ye finger is taken away: for we shall see that those wch are in H or L, and wch should

Transcription Notes:
mandc: reviewed, added detailed image descriptions and completed. Corrected some B's to D's, J's to I's, f's without crossbar to s's. https://transcription.si.edu/transcribe/8339/SIL-39088003881398_0044