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[[image:  drawing of a "U" shaped pipe where the left tube is larger than the right tube.  The outline of the "U" is labeled A (top left), B (bottom left), C ( bottom right), D (top right).  The connecting tube at the bottom is labeled G.  There is a liquid level in the tubes indicated by dotted line E 
D]]

When in ye syphons wch have one branch much more large than ye other, as in ye following figure, and we stop ye end of ye small branch with ones finger, and that ye great one being after that filled with water, we suddenly take away ye finger, ye first motion of ye whole water A B is retarded by ye difficulty of ye passage in G but ye motion through F C is much further in ye beginning than when ye two branches are of equal largeness: whence it happens that we put a little water into ye branch F C, untill it hath filled ye pipe at conjunction B C and if after ye end F hath been stopped with ye finger, we fill ye other part A B to ye horizontal line E B, and that we next take away ye finger on ye sudden, ye water will mount heigher than D as unto F, wch happens because that ye water of ye great branch althô descending gently makes ye water in small branch to mount 3 times as swift, and that all ye water moving to make an equilibrium, it did yet move after it was arrived there by ye acquired swiftness as in an uniform syphon, wch makes ye water of ye great branch yet descend and ye other mount to two or three inches above D, whence it redescends and after some balancings is stopped at last at ye same height in ye two branches below E F;  and though ye pipe A B should be full before ye stopping with ye finger, ye water would nevertheless spout 2 or 3 inches heigher than F if ye branch A B is larger than ye branch C D, for then ye descent and mounting in that large branch shall be very small and almost insensible; here is ye experiments wch have been made.

[[image: drawing of a "U" shaped tube L (left top), F (left bottom)G, (right bottom), I (right top). Superimposed over the L (top left) is a rectangle (representing tin vessel) A (top left corner), B (bottom left), C (bottom right),  D (top right).  The line A D is extended over to the right tube by dotted line H.  The left tube proceeds down from L on line A D, through the rectangle exiting line B D at E.  Below the rectangle there is a dotted line K M between left and right tubes.]]

I did take a vessel of tin A B C D with ye pipe E F of 4 inches wide wch was soldered to ye crooked pipe of glass F G H;  I filled ye vessel and ye pipe E F after having put my finger in H to hinder ye pipe G H, and when ye finger was taken away, ye water spouted unto I about three inches heigher than ye surface of ye water D A;  but when ye pipe of glass shall be 5 or 6 inches heigher than A D, ye water will mount there to about 4 inches heigher than H;  whence it will descend again, and at last make an equilibrium.  There is made ye same experiment in a pipe L E F equally large thrô out G H remaining always streighter than L E F, and ye water shall spout heigher than ye point H, as when ye vessel A D was on ye top of D F;  now in these cases ye water begins to mount sufficiently swift thrô G, and mounts yet a little swifter when ye water L E hath acquired motion, but that swiftness thro G H begins to diminish when ye water of ye two branches is arrived to an equilibrium, that is to say into ye height where it ought to stay in ye two branches as to that of ye horizontal line K M.  But if we put different liquors in ye two pipes, ye hightest will remain elevated in ye pipes heigher than ye other according to ye reciprocall proportion of their weights, of wch see ye rules.

Transcription Notes:
mandc: added detailed image descriptions. Changed some "B's" to "D's. Beware: some labels in the drawing to not seem to coincide with the description. For example "H" does not appear to be an opening to stop, should be "G?" "Pipe of glass F G H" should be ..."L F G I?" Etc. Detailed drawing: http://echo.mpiwg-berlin.mpg.de/ECHOdocuView?url=%2Fpermanent%2Flibrary%2FQERNH1MN%2Fpageimg&start=11&mode=imagepath&pn=119&ww=0.0684&wh=0.2067&wx=0.7406&wy=0.3332