on Rivers and Canals. 615 
This feparation and difperfion of the too great quan- 
tity of water into feveral channels is one caufe of their 
feldom overflowing the country near their mouths (f> , 
becaufe it gives a greater depreffion and declivity to the 
furface of the current, and thereby facilitates the run- 
ning down of the waters from the interior parts of the 
country, forafmuch as their beds are every where regu- 
lar and free from obftacles to their current. 
51. Notwithftanding the apparent oppofition to what 
has been faid in feveral other parts of this treatife, \ re- 
peat again, that this divifion and difperfion of the waters 
into feveral branches and channels when there is fuch an 
abundance of it as is fufficient to keep up the velocity both in 
the old and new channels , augments the declivity, and 
thereby facilitates the running off of all the back-waters 
from the inner parts of the country, as far as the bed is 
regular and free from obftacles, according to what is 
laid down above (N° 38.). 
But whenever this fuper-abundance of waters, fuffi- 
cient for keeping up the velocity in each channel nearly 
to what it was before the feparation or divarication, fhall 
be found wanting, it is certain, that this divifion and dif- 
perfion of the waters into feveral channels will only ferve 
to diminifh the velocity of the current in each, whereby 
(/) Another caufe thereof is pointed out above, N° 43- 
4 L a as 
