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68.

there will go out at that last twice as much water in ye same time since it hath been proved ye water will go out at that last twice as fast as thrô ye others:

  Whence is seen that to determine ye quantity of water wch ought to pass thrô ye hole of an inch, situate perpendicular it is necessary to determine how heigh above ye circular inch ye surface of ye water wch furnisheth ye running ought to be.

  Here is some experiments wch have been made to determine that height and ye quantity of water wch goeth out in a certain time:

     First Experiment

  We make use of a Tinn vessel M B of 2 foot long and 10 inches large, perced in C with a square hole of about 16 lines large where there was applyed 

[[image:  three dimensional drawing of a reservoir (left) showing a tube/spout annotated F with water flowing into a square box with labels as follows: lower left corner G; lower right corner B; line from front to back D E; small rectangular opening L near top of box; small rectangle on surface of water in far right corner of box M , with a hole labeled C spilling into a box labeled N]]

a small plate of copper peirced exactly of a circular figure of an inch diameter, this vessel being situated so that that hole was verticall, it was filled with water above ye hole stopping it with ye hand and ye water was permitted to run from a vessel F G wch was near it, in such quantity that passing all thrô ye circular hole C, ye upper surface of ye water of ye vessel might remain always about a line and a half heigher than ye hole.

  To make ye experiment right a hole must be made at ye side of ye vessel as in L a little heigher than ye circular hole C to serve to discharge ye super abundant water whereof ye height may be diminished as we please by means of a small plate of tinn wch is applyed there with a very viscous matter made of wax and turpentine.  There was also applyed another small plate of tinn M to two inches at ye [[strikethrough]] base [[strikethrough]] side of ye hole C and to a line heigher less by 1/4;  it was parallel to ye water of ye vessel, so that when ye water was [[?intended]] a little above as 1/4 of a line thick, we were [[strikethrough]] extended [[/strikethrough]] assured that ye upper surface was near above a line heigher than ye hole C and without this invention it would be very hard to be assured of it;:  because ye water makes ordinarily a small concave elevation of about 2 lines heigh along ye bodys its touches when they are moistened wch hinder ye exact observing of ye height of ye surface of ye water in respect of the hole C.  There was also in ye vessel a crossbeam D E to receive ye shoc of ye water wch should fall from ye other vessel into ye reservatory, that their be no waves made, and, that beam was distant about 3 inches from ye bottom of ye vessel, and was perced with many holes that ye water might pass it freely.  This being rightly disposed, ye hole was stopped with ye finger or otherwise and ye vessel was filled till ye water might pass three or 4 lines above ye small plate M, and afterwards ye water was permitted to run at ye same time thrô ye hole and thrô ye other vessel, and if ye water of ye vessel remained at ye height or 3 or 4 lines or mounted higher, it was diminished a little by ye discharger L, till very little water remained upon ye small plate M, as one fourth 

Transcription Notes:
mandc: Reviewed. Added omitted line. Image: http://echo.mpiwg-berlin.mpg.de/ECHOdocuView?url=%2Fpermanent%2Flibrary%2FQERNH1MN%2Fpageimg&start=11&mode=imagepath&pn=211&ww=0.1954&wh=0.2019&wx=0.4769&wy=0.5319