J86 
Analyses of Books, 
[Juki, 
much in excess of Rennell’s estimate, and nearly on a par with the Mississipi, 
as derived from the data of Captain Hall and Mr. Darby. Our Author con- 
firms this equality by the following comparison of the rain which may be supposed 
to fall within the range of the respective courses of the two rivers. 
Area of Area Annual ex- 
country Annl . of Annl. Total penditure Ratio to the 
above Delta, rain. Delta, rain, supply, by river. supply, 
sq. miles. inch, sq.mi. in. millions c.f. mill. cub. f. t. 
Ganges, 332000 50 28000 84 59500000 15768000 26 per cent. 
Mississipi, 8.86000 18 14000 60 53300.000 17344.800 32 ditto. 
The river discharge is smaller in India, because of the greater absorption by the 
dried-up soil, — the greater heat, — and greater consequent evaporation. In the 
Mississipi, the bulk of water is never so disproportionate at different seasons, as in 
the Ganges, being only as 10 to 1 ; and hence the great advantages it offers to steam 
navigation. 
The superficial profile or slope of a river forms a species of hyperbolic curve, be- 
tween the rapid declivities of its source among the uplands, and its tangential dissi- 
pation in the ocean. In proportion as the supply of water increases, the curve rises 
in the centre, the t« o extremes remaining stationary : the maximum rise must be 
looked for about mid-course, which may be set down for the Ganges, as between 
Benares and Allahabad. So backward are the generality of the world in observ- 
ing the ordinary phenomena of nature, that it was with difficulty Captain Prinsep 
could collect the following scanty materials on this interesting subject, in the 
Memoir on his New River Charts. 
Baro. 
Distance from 
Slope of the Greatest known 
Rise in low 
Place. elevation. 
the sea. 
Aver. 
annual rise. 
season. 
feet. 
miles. 
inches. 
feet. 
feet. 
AtFuttigurh, .... 550 
1150 
> 
10,0 ? 
7,0? 
Cawnpore, 0 
1070 
> 
15,0? 
10,0? 
Allahabad, 335 
930 
6 
45,6 
29,0 
Benares, 270 
800 
5 
45,0 
34,0 
Colgong, 130 
464 
4 
29,6 
28,3 
Jellinghee, 75 
297 
4 or less, 
26,0 
25,6 
Commercolly and 
Custee, not quite 
certain, ? 
250 
» 
22,6 
22,0 
Agurdeep, ? 
200 
? 
23,9 
23,0 
Calcutta, 10 
100 
1 
7,0 
6,7 
Dacca, (byRennell,) ? 
120 
? 
14,0 
There is an apparent anomaly hence deducible ; namely, that the slope of the 
river in any point above the mid-course, will be less during the rains than in the 
dry season ; which is altogether at variance with the laws of running water, but 
the explanation is readily found. “The bed of the Ganges, instead of having a 
continuous slope, consists of a series of pools separated by shallows or sand-bars, 
at the crossings of every reach, as would perhaps be the state of all large rivers 
emptied in an equal degree.” Where the river has an unlimited width, these are 
due to the abrading force of the current of greatest velocity, in sweeping round the 
bend of a reach ; in other places the effect may be increased by local resistance, 
such as is formed by the stone ghats at Benares, in front of which the stream has 
a depth of 52 feet at low water, whereas in the crossings of the reaches above and 
