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89. [[image: diagram of a cylinder with an inverted J pipe coming from the bottom annotated A B C D]] We took a pipe of 3 inches large at ye top of wch was soddered a vessel of a foot diameter. Ye figure of ye pipe was as in ye figure ABCD, ye lower part was crooked; we put ye reservatory AB at different heights to make different experiments. The water of ye reservatory being at 24 foot 5 inches heigher than ye hole D, ye spout mounted to 22 foot 10 inches; ye hole of ye going out was 6 lines, ye square of 22 5/6 is 521 13/36 therefore we say that as 25 ye square of 5 is to 251 13/36 so is 1 inch of the height of ye reservatory, above ye foot, to a little less than 21 inches wch ought to be added to 22 feet 10 inches to have ye height of ye reservatory according to ye preceeding table, wch makes 34 foot 7 inches near wch agrees well enough with ye experiment. The spout of 4 lines at ye same height of ye reservatory mounted but to 22 foot 8 1/2 inches, and was lower but 1 inch or 1 1/2 inch that that whose passage was 6 lines: but that of 3 lines was lower than that of 6 lines near 8 inches and was but 22 foot 2 inches. A reservatory of 12 foot 1/3 made ye spout at 6 lines leap to 12 feet that is a little more than according to ye rule. Another reservatory of 5 foot 1/3 height in a very large conduit ye passages being 3 lines, 4 lines and 6 lines cast ye spouts to near 15 lines below the surface of ye water of ye reservatory, and that of 3 lines differed but about one line 1/2 from that of 6 lines. By ye calculation ye square of 5 1/2 is 30 1/4 and by ye rule 25 feet is to one inch as 30 1/4 to 1 1/5 a little more wch would give ye height of ye reservatory only one line less than by ye experiment, wch is not possible to be observed. The small spouts in small heights loose very little by ye shoc of ye air, and are little less heigh than those of 6 lines, provided ye pipes are large enough; ye overplus of ye length doth not augment ye height of ye spout, nor ye quantity of ye running, or of ye expence of ye water when wee keep ye pipes full. For ye spout wch the water can sustain that ought to go out is always of equal force, and supports weights according to ye greatness of ye hole of its passage. The reservatory being at 26 feet one inch ye hole of 6 lines, it cast to 24 feet 1/4 being 588 1/16, as 25 is to 588 1/16 so is 1 inch to 23 inches 1/2 near, wch ought to be added to 24 feet 4 inches to make ye height of ye reservatory wch is therefore 26 feet 1 inch, as ye experiment shews. The reservatory being at ye same height with a passage of 10 lines spouted to 23 feet 9 inches, and thrô a hole of 3 lines it spouted to 22 foot. In ye first of these experiments ye default of ye height proceeds from hence that ye passage was too large for a conduit of 3 inches and that ye water going very swift had much rubbing; and in ye second ye smallness of ye spout wch having much air to pass thrô was considerably retarded, and its height diminished, as is explained in ye first and second consideration. The water of ye reservatory being at 35 foot height less by half an inch thrô a passage of 6 lines ye spout was cast to 31 feet 8 or 9 inches; and by ye rule ye square of 31 feet 1/2 being 1002 near, and 25 is to 1002 as 1 to 40 inches near, that is 3 feet 4 inches wch being added to 31 feet 8 inches make 35 feet; so that experiment is conformable to ye rule. Thô ye same reservatory thrô a hole of 3 lines spouted to 28 feet; one of 4 lines to 30 feet and one of 15 lines to 27 feet only for the same reasons wch have been said; viz that in ye last experiment ye conduit of ye pipe was not large enough for ye grossness of ye spout, and for ye expence of ye water, and in ye two former, that ye height being great ye air did too much resist ye small spout of 3 and 4 lines I made also experiments with a reservatory of 5 feet heigh, and ye spouts followed ye same rules, ye passage of 6 or 7 lines made ye heighest spouts.
