3 DR. HOOKER'S MISSION TO INDIA. 
winter; and the main trunk is additionally swelled by the summer 
rains of the plains. The Ganges thus levies contributions from the 
precipitated moisture of all seasons in the year, of winter's snows and 
of periodical summer rains. The courses of its feeders in the 
Himalayah (which are legionary in number) are along valleys and 
down hills, whose uniform steepness is without parallel in any moun- 
tain-chain, and yet never over precipices: they are consequently most 
favourably disposed for the collection of detritus, and the effectual 
transport of this to the main trunks. Hence the enormous sand-banks 
in the eastern channel of the river, which, shifting along miles of its 
course after every season of flood, render its navigation the most 
perilous perhaps of any stream of its size. These vast beds give 
rise to dust-storms, over which Simooms, in slender pillars several 
hundred feet high, stalk like moving columns, glistening with the mica, 
quartz, and hornblende of the far-distant mountains—minerals foreign 
to the soil of those plains of India on which they are deposited. In 
the summer, again, the rains of the plains on both banks, rising above 
the mean level of the soil, discharge their water into the stream, loaded 
with a fine silt, which forms banks, often alternate with those of the more 
remotely derived sand, and from its impalpable nature is transported fur- 
ther down, and contributes more directly to the formation of the Delta. 
The borings in the Sunderbunds, through the various strata, have 
been carried by the officers of the E.1.C.S. to a great depth and with 
most interesting results. Such is the origin of the Sunderbunds and 
green islets along whose palmy banks we steamed our way, now passing 
little villages or rather congregations of huts, each with its Toddy 
Palm and patch of cultivation, and again the densest jungle of mangrove 
and creepers infested with tigers. Occasionally, cleared places exhi- 
bited park-like features, with the spreading Banyan, the dusky yellow 
Tamarind, leafless Cotton-trees and scarlet Terminalias. In the after- 
noon we were passing Garden-Reach, with the noble Garden-House on 
the left, succeeded by the river front of the Botanic Gardens itself. 
Opposite stand the beautiful house,grounds, and gardens of Sir Lawrence 
Peel, whose walls and trellises were blue with the noble Ipomea pur- 
pureo-cærulea, and the beds scarlet with Poincettia. Passing along flat 
green banks, with superb houses and gay gardens, we left behind us 
the sdy aah ic isa Reach : the country, still jungly on the left, 
p ting the ** Course" crowded with gaily-dressed 
