1904.] HAUPT— THE MISSISSIPPI RIVER PROBLEM. 91 



they are of great utility. Few practical problems admit of so posi- 

 tive a solution." 



Perhaps the best evidence on this much- mooted point will be 

 found in the answer of Nature herself, so that an examination of 

 the bed below the head of the distributaries will throw much light 

 on the subject. Taking that portion of the delta below the Forts, 

 which is in a state of nature and unleveed, it is observed that in 

 the reverse curves swinging around these defenses, where the radii 

 are but two and one and one-half miles, the greatest depths are thirty- 

 one and twenty-nine fathoms respectively, due to the reaction of 

 the sharp concave banks and the reduced width. As the radius 

 lengthens to five miles the thalweg depths shoal to thirteen, 

 twelve and eleven fathoms, and the river also widens gradually to the 

 crevasse known as '' The Jump," where the width exceeds a half 

 mile and the depths increase to fifteen fathoms abreast of the open- 

 ing, and to thirty-nine fathoms and '* no bottom " at a quarter of a 

 mile lower dozvn, with over fifteen fathoms for several miles. 



In this instance, therefore, the depth below the crevasse, instead 

 of being less, is more than twice as great, and it is not due to local 

 curvature but apparently to impact, due to the suction or set of 

 the currents toward the right bank. 



Continuing down stream as it widens out to a mile in breadth, the 

 bed shoals to about six fathoms at the head of the Passes, which 

 may be regarded as three crevasses, and yet it will be found that in 

 each one of these distributaries the depths exceed those of the undi- 

 vided stream. In the Pass a 1' Outre it is twelve, in South Pass 

 fifteen, and in Southwest Pass thirteen fathoms., with ''no bottom," 

 all at the points of incidence of the divided currents. Again in the 

 Pass a r Outre at the crevasse which formed in 1891, the depth 

 abreast the opening is thirteen fathoms, and one mile below it is 

 fourteen and one-half. This same stream again divides into two main 

 branches, showing eight and one-quarter fathoms below the point of 

 separation in the more direct channel, and eleven and one-half along 

 the sharper concavity of the Southeast Pass, due to reaction of the 

 bank. Without further elaboration, the same general results may be 

 seen wherever a crevasse occurs, and there is no indication of shoal- 

 ing due to the escape of the excess of the flood waters or loss of 

 volume. On the other hand there is a very marked benefit observ- 

 able in the relief afforded to the stream, for these openings enable 

 it to discharge a large portion of its sediment beyond the banks 



