1879.] Discharge of large Rivers in Assam. 7 
‘From chart the length ¢ e = 200 feet (vide Fig. 5). Make e G@ = Ge. 
Through G draw G K, showing a mean direction of flow of floats, 7. e. 
265°. 
Draw f G h perpendicular to G K and the lines ef, eh perpendicular 
tofg h. 
Then for computation of discharge ; the area of the section from c¢ to 
12 + 10 )) ee 
e is very nearly [200 x Cos 9° x ( 5) 
From the velocity measurements— 
The meantime of passage of 10 dises thrown in at ¢ = 12:5 
c tubes, each 10 ft. long, at e = 14:5 
7 ys te fb. long, at- eo =" 12-0 
etc Soccaels. of rs dises thrown in at e = 12:0 
4 tubes, each 8 ft. long, at e = 14:5 
1 3 ” ” 3 ” at — 12'0 
Assumed meantime of passage for section is 13-5— 
f oO 
The mean velocity per second required for section is’ = 3 = ig 
and AV = discharge, or number of cubic feet of water passing through 
c to e in one second of time. 
Mag£ Peariag 
of this linews £* 
Soundings 
tw ES & Inches 
OK Welocity $# ) 
