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100.
also 2 inches: all ye water N O shall be employed. Now 13 foot is to its half 6 1/2 as 6 1/2 to 3 1/4, therefore ye height of ye water being P Q of 3 foot 1/4 above H, the spout can be but 3 foot 2 inches and some lines according to ye fules above: and by consequence we shall see ye spout H M decrease till it is but 3 feet 2 inches and some lines, and ye water O will keep ye height of ye water to ye height Q P:
But if we stop ye hole I, ye spout thrô H will begin to increase till it goeth to H M and at ye same time ye water of ye conduit will be elevated above P till it is in ye reservatory A H at its first height: It will be regulated after ye same manner in other like cases.
If ye heights of ye reservatorys were extreemly great, ye spouts will be dissipated by ye incounter and violent shoc of ye air and instead of going heigher than ye spouts of some reservatorys less heigh, they would go much less heigh.
I have made ye following experiment.
We put into a small pipe of an inch large and of 8 inches long, tied strongly in ye notch of ye string of ye crossbow, and having bent it it was elevated perpendicularly, and ye small pipe filled with water; ye water being pushed by ye force of ye crossbow went out and incountered ye air with violence was very much scattered: Those wch were at ye side could not see ye spout mount, but they saw many small drops fall near 20 foot round him who held ye crossbow, which who did assure us he saw ye water mount to about 30 feet: Now that swiftness would belong to a reservatory of more than 600 foot, and ye spout ought to be 300 foot according to ye rules.
Another Experiment.
I charged many times a pistol of 4 inches heigh with water instead of balls and shooting that water 20 foot against a door elevating the pistol according to an angle of 45 degrees near to hinder ye water from falling, there went not one drop thither. I shot ye second time 10 foot, and it happened ye same; and when he wch shot had advanced and lifted ye end on heigh, he perceived some small drops to fall; lastly we shot 7 foot against a paper put on ye top of a door then ye paper was all wet, and we found that ye water was scattered to 2 foot diameter and haveing shot another time 8 foot distance ye paper was not wet. If we calculate this water as a cylinder of 5 lines large and 4 inches heigh, and divide ye product by a surface of 2 foot large we shall find that its thickness shall be but 1/70 of a line: For ye solid of ye square of 5 by 48 is 1200, and ye solid of ye square of 288 lines by 1/70 is a little less than 1200 cubic lines and ye strait cylinder is of 943 cubic lines, and that of 2 foot diameter for its base is of 931: It happens therefore that ye water being reduced yet to a lettle less thickness as when we shoot 10 foot, it is seperated into small drops whereof some are elevated into vapours, and ye others fall down: but they are imperceptible.
The same effect is seen when a bubble of soap is broaken: for ye particles of its water wch are very small are elevated invisible vapours and ye rest falls. A stream of water thrô a hole of half a line below 100 foot incountering ye hand in spouting transverse, is put also into vapours.
It may be objected that if we shoot water in cannon of a foot bore ye water would go further than 100 foot: but we do not agree to this for it will not go 100 foot, as may be proved and experimented.
Now this swiftness is so great no accessible reservatory, can give a paralel: for since ye first swiftness of ye water wch goeth out there, makes 200 foot in a second as do ye sound, let us suppose that ye reservatory makes in falling 13 foot in a second it shall make 26 foot horizontaly: Ye product of 13 by 10000 is 130000, whose square root is about 360; as 13 to 360 so is 1 second to 28 near. If we suppose therefore that a globe of water of a foot is accelerated according to a series of odd numbers, wch Transcription Notes:
mandc: Reviewed. Changed is to 13; 1/4 to 3 1/4; J to I; How to Now. There may be an error in the Desaguliers translation on page 215 (scan 258) where it says: water of the conduit will rise to B" probably should read as in this ms "rise to P." B is the level of the reservoir, P a point above the nozzle outlet.
