RECLAMATION OF TIDE LANDS. 381 



it. Where the material contains a large percentage of clay, a smaller 

 cross section may be safely used than where the material contains 

 a large amount of sand and vegetable matter (fig. 2). Experience 

 has shov\Ti that the top width should be two times the square root 

 of the height, with, bank slopes on the water side of not less than 3 

 horizontal to 1 perpendicular and on the land side as steep as the 

 material will stand without sloughing, which is usually 1 or 1^ hori- 

 zontal to 1 perpendicular. This has proved to be the most econom- 

 ical cross section that can be constructed to safely withstand the 

 water that may come against it. When the material is more or less 

 sand or sandy loam, to insure safety it is necessary to increase the 

 slope on the coast side from 3 to 1 to 4 to 1, and where exposed to 

 the influence of the wind it ought to be 5 horizontal to 1 perpen- 

 dicular in order to break the force of the waves and prevent washing. 

 Where the material is of a peaty nature with a mass of fibrous roots, 

 a better practice seems to be to increase the top width to that of 

 the height and make the slopes on either side 2 to 1. This form 

 seems to withstand the seepage better than a narrow top and a 

 slight slope when the material is of a fibrous nature. 



The Mississippi River from Cairo to New Orleans is restrained by 

 levees built of sandy loam. Large areas of Nova Scotia and New 

 Brunswick have been protected for centuries by dikes built of marshy 

 soil, and the dikes that protect Holland from the sea are in most 

 part made of sand. There is no occasion for failure on the Atlantic 

 coast if the embankments are properly located and carefully con- 

 structed, but great care must be given to the details of the work to 

 insure success. 



SPECIFICATIONS FOR BUIIDING EMBANKMENTS. 



The ground should be cleared of all coarse vegetable matter and a 

 strip in the center one-half as wide as the base should be broken up 

 with a plow or spade (fig. 3). Where the ground is very wet or 

 covered with water, ^ 



a successful method .--''" "~^^^ 



is to excavate a ditch 

 5 feet wdde and about —. . -— ■' " 

 18 inches deep along 



1 .1 » . 1 1 Fig. 3.— Method of preparing base in marsh lands. 



each side of the base 



of the embankment 6 feet inside the toe and parallel therewith, placing 

 the earth excavated on the outside of the ditches so as to form the 

 toes of the slopes, the trenches being refilled with new material as 

 the bank is made. This preparation will disclose any underground 

 timbers and channels and prepare for a proper union between the 

 base and the new material. All stumps and logs should be removed 

 from the base and should there be any old trenc-hes they should be 



MUCKTOITCH 



