INVESTIGATION OF FLOW OF WATER IN UNIFORM CHANNELS. 363 
cm., and it was possible to read accurately to ‘01 cm., correspond- 
ing roughly to 34, of a cubic foot, or say } of a pound of water. 
The temperature of the water was carefully observed through- 
out the entire process, but it varied very slightly from 12° C., it 
being at the time mild and settled winter weather. Any readings 
which gave differences, not in close agreement with neighbouring 
differences, were subsequently checked by taking several additional 
readings over that portion of the scale. By interpolation, Table 
III. was finally constructed from the observed readings, giving 
the number of cubic feet in the tank up to any reading on the 
scale, the zero being taken at 98 cm. To measure the mean rate 
of flow for any experiment it was then only necessary to observe 
the reading of the scale before the water was turned into the tank, 
and after it was diverted to the drain, and to note accurately the 
length of time the water was flowing into the tank. For the 
Table III. 
Mean temperature = 12° C. 
ie Scale Cubic feet of Scale jCubic feet of Scale |Cubic feet of Scale Cubic feet of| 
98 | 0 73 | 13:058 || 48 | 26088 | 238 | 39:23 
97 | 0515 | 72 | 13577 || 47 | 26604 || 22 39°768 
96 1-034 7 14098 46 “127 21 | 40-300 
95 1°563 70 | 14619 45 | 27°651 2 40° 
i 2-092 69 | 15:138 44 | 28°174 19 | 41°371 
3 2-621 68 | 15°655 43 | 28698 | 18 | 41 
4 3-145 67 | 16:176 42 | 29°222 ce 2°439 
3°663 66 6°696 41 | 29-747 16 | 42°969 
) 4181 65 | 17°218 40 | 30:272 15 494 
89 4699 64 | 17°739 39 | 30°794 14 | 4402 
88 5°223 63 | 18°265 38 | 31°314 13 | 44-555 
: 5°749 62 | 18°785 oT: 156 1 5°097 
86 6°276 f 19°304 36 | 32°367 1l | 45°642 
) 6°802 60 | 19°824 35 | 32°8 10 | 467186 
84 7-328 » | 20° 34 | 33-421 9 | 46°729 
83 7855 3 «| 20°865 33 | 33 8 | 47°261 
82 8°371 7 | 21°83) 32 | 34472 7 | 47-795 
‘ 8°886 3 | 21912 81 | 35:000 6 | 48°332 
) 9°410 5 | 29°435 30 | 35°524 5 “861 
) 9-936 . | 22959 29 | 36°049 4 | 49°387 
3 | 10°454 3 | 23-480 28 | 36°572 3 | 49-920 
T | 10°972 » | 24-001 27 | 37-097 2 | 50°456 
5 | 11-490 24523 26 | 37°620 1 | 50-988. 
4 009 50 | 25-045 25 | 38157 0 | 51°506 
_74 | 12530 || 49 | 25-563 || 24 | 38695 
The scale read from 100 at the bottom to 0 at the top. 
