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42.

easily support ye vessel below ye water was put in; shall be at some trouble to support it for it should weigh as much as if it  had been full to ye height of that body after it had been full to ye height of that body after it had been taken away; and he who sustains ye cord shall be discharged of so much of so much of his weight as if ye weight of ye water whose place ye cylindric body occupys; ye reason is that then that body ought to follow ye same rules as ye bodys wch are sustained in ye water whose weight is diminished by he weight at a like volumn of water as that it occupys and by consequence he that sustains ye cord ought to perceive himself discharged at a weight of water equal in bulk to ye cylindric body and ye other wch has his hand under ye vessel, besides ye weight of ye vessel ought to sustain as much weight as that at wch ye other ought to be discharged, and also that little water wch had been poured in.

  Sometimes bodys lighter than water go to ye bottom by a cause sufficiently easy to explain; see and experiment: take a cylindric glass of 7 or 8 inches high and of three or four longe as A B C D wch hath an hole E at ye middle of ye bottom at about 3 lines large fill ye vessel

[[image: line drawing of a cylindrical glass vessel A C D B open at top F and an opening in the bottom E.  The center of the tube is labeled H.  At the bottom of the tube is a semicircular dotted line C I L M D starting at C ending at D, the left side labeled f and the right side r]]

holding a finger under E, and put on ye top of ye water a small ball of wax of wch may pass through ye hole e and when ye water shall be calm and stopped take away  the finger and let ye water run; ye wax will descend after ye same manner as ye surface of ye water and will pass thrô E with ye last water.  but if you give a great circular motion to ye water, let it be by turning it cross ways against ye sides of ye glass or otherwise, when you shall take away ye finger from ye hole you will see ye ball forewith descend before ye water had begun to run, and make a void place in ye middle of ye water ye air is insinuated as from H to E, and that void place is not filled up till ye whole water is run out, and we may always see a column of wreathed air from ye top at ye water to he hole.

 This effect is explained in this manner ye water wch is in ye Hemisphere C I L M D is pushed  towards E, when ye water is calm and without any considerable motion, as hath been proved, and if proceedes so that to that wch goes out before that wch is in H is descended there; but when ye water hath a great circular motion ye later rawls towards N or I or r and F cannot arrive towards E before 4 or 5 turnings round, and also they are carried towards ye hole at ye glass because they are pushed according to ye tangents at ye circles that they describe; whence it follows that ye entire column F E falls fourth with and passeth thrô with that little ball of wax that is above it;p and because that ye water wch is at ye side of that column wch is run throw, cannot fill up its place so swift, because of its circular motion wch has not that direction, it is necessary that ye superior air insinuate there by its weight and it spring, and remain there till all is run out:

  It happens sometimes that ye small ball is not directed upon ye column, and then it is carried a little aside between ye two walls; and also if it returns towards ye midle, ye column of air pushes it back towars ye midle, ye column of air pushes it back toward ye sides of ye glass by it spring: but at last it enters in ye void column and passes after various thrô ye hole turning very swift before half ye water is run out:

  It is for ye same reason that if there is a great hole in ye bottom of a deep water as in a river or in sea, where ye water runs towards places a great distance off as it is said that ye caspian sea runs into ye Euxin, ye water draws with it ye vessels wch pass near ye whirl pool; for ye water falling after that manner takes always a circular motion and produces ye same effects in regard of ye vessels wch pass over it, as ye water turning round in ye glass A B C D in respect of ye ball of wax.  It is said also that there is in some seas near to Sweadland a like turning round of ye water where ye  vessels are overturned, and that there is seen sometimes wracke in a place of ye neighbouring sea wch is low.  It is easy to judge that ye water takes up more time [[?]] thrô ye hole E when it turns round than when it doth not since in ye first case air occupies one part of that hole.

Transcription Notes:
mandc: "Sweadland" = Sweden. http://echo.mpiwg-berlin.mpg.de/ECHOdocuView?url=/permanent/library/QERNH1MN/pageimg&start=11&mode=imagepath&pn=127&ww=0.7316&wh=0.4583&wx=0.063&wy=0.4467