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69.

of a line thick;  and that it remained sensiblely in that state a little vessel N, to receive ye water wch should run thrô ye hole F, and after it had stayed 30 second precisely it was suddainly drawn away and ye quantity of water wch was within was measured:

  To observe ye time of ye running there was made use of a pendulum of fine thread charged at ye end with a ball of lead of 8 lines diameter;  ye length of ye thread was 3 feet and 8 lines diameter; ye length ye interval was 3 feet and eight lines from ye point of suspension to ye center of ye ball, ye pendulum beat seconds and we were assured of it by comparing it with a pendulum or clock very exact white marked seconds;  ye same experiment was reiterated many times, and we found that there passed in 60 seconds thrô that hole of an inch, when ye upper surface of ye water of ye vessel was 7 lines heigher than ye center of ye hole;  about 13 pints 3/8 Paris measure, each pint weighing 2 pound less by 7 dragms.

  In places nearer ye Line, ye pendulum ought to be shorter because that ye motion of ye surface of ye earth in these places is greater than in France.  Mr Richer, and Mr Varin have made observations;  ye first at ye cayenne, where it was found shorter by 1 1/4 line, and ye other in ye Ile of Goree near Cape Verd, where it ought to be only 3 feet and 1/2:  This effect is demonstrated in this matter:  D A B C represents a meridian passing thrô ye poles B C, and A E F is ye equinoxial line G H M N B C, [[strikethrough]] and ? [[/strikethrough]] is ye parallel of Paris:  If we suppose ye motion of ye earth from west to east, a stone wch should be in A would fly off from ye earth by a tangent;  and because ye point A will go also swift, if ye motion towards ye center K did not surmount its motion it shall be elongated from ye earth according to ye tangent line AI:  But that motion toward ye center being stronger ye stone shall not be elevated, but it will nevertheless loose one part of its tendance to motion towards K:  Ye same thing shall happen to a stone wch shall be at ye point G, but its tendance to motion by ye tangent shall be much less strong, 

[[image: drawing of a circle A B C with two latitudinal lines, one smaller G H M N, the other maximum (equator) A E F.  From the center of the circle K there is a line K G ending outside the circle at O.  Vertically from K there is a line K A, and from A there is a tangent line A I.  From G there is a tangent line G L.]]

because ye point A moves swifter than ye point G:  Therefore it will less hinder a stone wch falls from G towards K ye center of ye earth, and likewise ye oblique situation of ye small circle G M in regard of ye line By K, may yet diminish a its regarding towards ye center:  For I L ye oblique line at G K being equall to G O ye point L shall be less distant from K than ye point O.  By these two causes ye stone being loose in it will descend slower towards A than ye stone M L will towards G.  Therefore ye motion of ye weight of a pendulum shall be slower toward A than G and by consequent to make their beatings

Transcription Notes:
mandc: Reviewed. Added omitted sentence. "nearer ye Line" means "near the equator" not to be confused with "line" measure of one-fourth of a barleycorn (about one-tenth of an inch). The ms must be in error where it gives nonsensical points "G H M N B C" and should read "G H M N." Expanded image description. Image: http://http://echo.mpiwg-berlin.mpg.de/ECHOdocuView?url=%2Fpermanent%2Flibrary%2FQERNH1MN%2Fpageimg&start=11&mode=imagepath&pn=211&ww=0.1393&wh=0.1752&wx=0.6515&wy=0.5878url=%2Fpermanent%2Flibrary%2FQERNH1MN%2Fpageimg&start=11&mode=imagepath&pn=211&ww=0.1414&wh=0.163&wx=0.6494&wy=0.6049