636 Miniature Physical Geography. [November, 
obvious. Steamers can come alongside the steep bank ; they 
cannot get near the other. In any case, however, such set- 
tlements cannot be permanent. If they were built on the 
shelving bank the river would be constantly receding from 
them, and they would have to follow it. As it is they have 
to recede before the advancing river. I was informed at one 
place (Point Pleasant), on the Mississippi, that the river had 
advanced nearly three miles in sixty years. In 1876 I came 
across an instructive example of this kind of action. When 
I was in Lancashire a gentleman showed me a map of his 
estate made in 1747, in which year the River Lune ran, if I 
remember right, within a hundred yards of his house. In 
1876 the river was fully one-third of a mile distant, and a 
river-terrace about 50 yards farther off marked the limit of 
the swing of the stream in that direction. As the river forms 
the boundary between two properties, belonging say to A and 
B, one gains while the other loses, as the channel shifts. In 
this case A gained and B lost ; whereupon B put up a stone 
groin, to throw the force of the stream on A’s bank, that he 
might regain some lost ground. A in return put up a similar 
groin, to catch the brunt of the stream and turn it back upon 
the opposite bank. When I was there I saw several such 
artificial constructions, which will probably have the effeCt 
of checking the swing of the stream. 
On the Mississippi I have seen great masses of the steep 
bank fall, and felt in a large steamer the wave produced. 
Mr. Bates, however, has a striking passage describing similar 
falls on the Amazons. “ We saw the work of destruction,” 
he says, “ going forward on the other side of the river, about 
3 miles off. Large masses of forest, including trees of colossal 
size, probably 200 feet in height, were rocking to and fro, and 
falling headlong one after another into the water. It was a 
grand sight : each downfall created a cloud of spray ; the 
concussion in one place causing other masses to give way a 
long distance from it, and thus the crashes continued swaying 
to and fro with little prospeCt of a termination.” 
IV. The Formation of a Cut-off. 
Under certain circumstances the aCtion of a river upon its 
banks produces a curious effeCt. This I have seen in mi- 
niature on one occasion only. On the muddy flats of Pegwell 
Bay a little stream bent round in a great loop something like 
the capital Omega in the Greek alphabet. The flow of the 
water past the curves caused the concave banks to recede, 
thus narrowing the neck of land which separated them. 
