Ganges and Burrampooter Rivers , 
taken away. This is, however, the moil: rapid change that I 
have noticed ; a mile in ten or twelve years being the ufual 
rate of incroachment, in places where the current drikes with 
the greatefl force, namely, where two adjoining reaches ap- 
proach neared: to a right angle. In fuch fituationsit notunfre- 
quently excavates gulfs * of confiderable length within the 
bank. Thefe gulfs are in the direction of the dronged parts of 
the dream ; and are, in fa£t, the young fioots (if I may fo exprefs 
myfelf J which in time drike out and become branches of the 
river ; for we generally find them at thofe turnings that have 
the fmalled angles -j-. 
Two caufes, widely different from each other, occafion the 
meandering courfes of rivers ; the one, the irregularity of the 
ground through which they run, which obliges them to 
wander in qued of a declivity ; the other, the loofenefs of 
the foil, which yields to the friction of the border of the 
dream. The meanders in the fird cafe, are, of courfe, as 
digreffive and irregular as the furface they are proje&ed 
on : but, in the latter, they are fo far reducible to rule, 
that rivers of unequal bulk will, under fimilar circumdances, 
take a circuit to wind in, whole extent is in proportion 
to their refpeflive breadths : for I have obferved, that 
The Count de buffon advifes the digging of fuch gulfs in the banks of 
ordinary rivers, with a view to divert the current, when bridges or other build- 
ings are endangered by it. 
f The courfes of thefe branches at the efflux, generally, if not always, become 
retrograde to the courfe of the river : for, a fand bank accumulating at the upper 
point of feparation, gives an oblique direction upwards, to the ftream, which would 
otherwife run out at right angles. This fand bank being always on the increafe^ 
occalions acorrofion of the oppolite bank ; and by this means all, or moil of the 
outlets have a progreffive motion downwards ; as I have before remarked of the 
Jellinghy River, in the foregoing page. 
Vol; LXXI, p 
when 
