206 report— 1877. 



Volume in cubic yards at the bar removed in reference to a 20-feet channel. 



A part of tbe material bas fallen over the submerged jetties during their con- 

 struction, or has been driven back by the waves from beyond the sea-ends of the 

 jetties, and lodged outside on their sea-slopes ; 1,000,000 cubic yards, at least, have 

 piled themselves up against the outer or sea side of the jetties, an enduring and 

 solid bulwark against the storms. The remainder has gone far to the westward, no 

 doubt carried there by the prevailing westward coastwise current. 



This so-called " littoral current " is a current generally existing and has a west- 

 ward course. Whether it is caused principally by the prevailing north-east winds 

 or by a more constant and stronger influence, is somewhat doubtful. There is 

 strong evidence, from an examination of the general formation of the coast of 

 Louisiana and Texas, from the eastward bend of the lower part of the Mississippi 

 river toward that direction, by the excess of accumulation of sediment and con- 

 sequent shore-formation westward, and from other observations, that there is a 

 distinct, constant, and deep, moving westward, littoral or coastwise current, strong 

 enough to remove far from the mouth of the new channel the .sediment carried out 

 by the river, and which will postpone for a century or two the re-formation of the 

 bar. 



Mr. Eads, indeed, contends that this current driven westwardly passes beneath the 

 river-discharge, and that it thus has to excavate more room for itself as the volume 

 of water passing through the jetties becomes stronger. However this may be, the 

 facts are as stated ; and in any case it does not appear probable that any necessity 

 for extending the jetties, after a depth of 30 feet shall have been secured by them, 

 will occur for a considerable period. 



Mr. Eads, in discussing these works, lays especial stress on the assistance he 

 derived from the advice of Sir Charles Hartley, C.E., whose experience at the 

 mouth of the Danube is so well known in England. 



Up to March in this year Mr. Eads had expended about 1,500,000 dollars, and had 

 received the instalment due to a depth of 20 feet, viz. 500,000 dollars. 



Vessels of 22-feet draught have, I understand, passed through the South Pass to 

 New Orleans during the month of April ; and it may safely be concluded that ere 

 long New Orleans will be a port open to vessels of the larger sizes now used in 

 commerce. 



It would occupy too much space to show what will be the effect of these works 

 on the trade of adjacent portions of the United States. The distance from St. Louis 

 to New Orleans by railroad is 658 miles, as against 914 to Baltimore, 974 to 

 Philadelphia, and between 1,100 and 1,200 to New York. Thus New Orleans will 

 be the nearest port of importance for the rich districts of Illinois, as well as for 

 Missouri, Arkansas, and Texas : there can thus be little doubt that, with the intro- 

 duction of fresh capital which a settled government would attract, a great future 

 is in store for this city. 



On the Jetties of the Mississippi. By Captain D. Galton, C.B., D.C.L., F.B.S. 



