TABLE VI.-DISCHARGE IN CUBIC FEET PER SECOND OVER TRAPEZOIDAL WEIR HAVING END SLOPES OF 5 (VERTICALLY) TO 1 (HORIZONTALLY).

Values derived from large scale plotting of Authors' experimental results.

TABLE VII.-DISCHARGE IN CUBIC FEET PER SECOND OVER
RECTANGULAR WEIR WITH END CONTRACTIONS.

Based upon Boise results (Trans. Am. Soc. C.E., vol. lxxvi, p. 1076,

NOTE.-Barr's results are taken from Engineering, vol. lxxxix (1910), p. 473, Table IV.

The formula used for the V notch is Q= 2.48 H2-47, in which Q is the discharge in cubic feet per second and H is the head in feet.

TABLE IX.-COMPARISON BETWEEN ACTUAL DISCHARGES OBTAINED AT BOISE AND THOSE GIVEN BY AUTHORS' FORMULA FOR RECTANGULAR WEIRS WITH CONTRACTIONS

NOTE. Boise results taken from Trans. Am. Soc. C.E., vol. lxxvi, p. 1076. The Boise discharges for the 2-foot and 3-foot weirs are considered somewhat large owing to proximity of bottom of weir pool. The correction required is probably about per cent. for the 2-foot and 1 per cent. for the 3-foot weir at 12 inches head, and proportionately more for greater heads. These corrections would operate in reducing the differences in discharge given above.

TABLE X.-COMPARISON BETWEEN ACTUAL DISCHARGES OBTAINED BY FRANCIS AND THOSE GIVEN BY AUTHORS' FORMULA FOR RECTANGULAR WEIRS WITH CONTRACTIONS,'

COMPARISON BETWEEN ACTUAL DISCHARGES OBTAINED BY FTELEY AND STEARNS AND THOSE GIVEN BY AUTHORS' FORMULA FOR RECTANGULAR WEIRS WITH CONTRACTIONS,2

1 Francis's results are from p. 127, Hamilton Smith's "Hydraulics," 1886 edition.

2 Fteley and Stearns' results are given on pp. 102 and 103, Hamilton Smith's "Hydraulics," 1886 edition.

TABLE XI.-COMPARISON BETWEEN DISCHARGES OBTAINED BY USING HAMILTON SMITH'S COEFFICIENTS AND THOSE GIVEN BY AUTHORS' FORMULA FOR RECTANGULAR WEIRS WITH CONTRACTIONS.

NOTE.-Hamilton Smith's coefficients "For Weirs with Full Contraction" as given on p. 132 of his "Hydraulics" have been used. It should be noted that his coefficients for weirs up to 10 feet long are deduced from experiments on weirs with contractions, whereas for longer weirs he made use of experiments on weirs with suppressed contractions, and on this account there may be slight errors in his coefficients for longer weirs.