CHAP. XXIX.] ANNUAL INCREASE OF DELTA. 153 



had remained. Mr. D unbar, also an engineer in 

 great practice in Louisiana, assured me that on com 

 paring the soundings lately made by him with those 

 laid down in the French maps of Sieur Diron, pub 

 lished in 1740, he found the changes to be quite incon 

 siderable. On questioning the pilots on the subject, 

 they stated that the changes from year to year are 

 great, but are no measure whatever of those worked 

 out in a long period, for there seems to be a tendency 

 in the action of the tides and river to restore the old 

 soundings. 



Captain Grahame, also a government surveyor, on 

 comparing the north-east pass with the charts made 

 a century before, found it had not advanced more 

 than a quarter of a mile, and that in the same interval 

 the principal variations at the pass a Loutre had 

 consisted in the filling up of some bayous. Even if 

 we could assume that the progress of the whole delta 

 in twenty-five years was as great as that assigned by 

 Linton to one or two narrow channels and banks, 

 it would have taken several thousand years for the 

 river to advance from New Orleans to the Balize ; 

 but when we take into our account the whole breadth 

 of the delta, or that part of it which has advanced 

 beyond the general coast-line, above 100 miles across, 

 we must allow an enormous period of time for its 

 accumulation. 



The popular belief in New Orleans, that the pro 

 gress of the banks near the mouths of the river has 

 been very rapid, arises partly from the nature of the 

 evidence given by witnesses in the law courts, in 

 cases of insurance. When a ship is lost, the usual 



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