EMBANKMENT. 



ity of scientific men has been exer- 

 cised to invent various modes of re- 

 sisting the force of the sea. In some 

 exposed points piers of solid oak have 

 been made, which oppose a smooth 

 surface obliquely to the force of the 

 waves ; in others, rows of piles have 

 been driven in, forming lines at right 

 or oblique angles to the line of the 

 shore, in order to intercept the waves 

 and break their force before they 

 reach the bank. In a place where 

 the rounded stones called shingles 

 were usually thrown up by the waves, 

 and the bottom was a strong clay, 

 their retreat has been intercepted by 

 rows of strong piles driven in a line 

 along and parallel to the shore, and 

 covered with boards nailed to them 

 on the land side. By this means the 

 sea has been made to provide the 

 materials of the embankment, and to 

 lay them down. In one night the 

 shingles have been thrown over the 

 piles, and, being retained by the board- 

 ing, have formed a perfect wall. A 

 second row of piles between the first 

 and the sea, and a third if required, 

 forms a sea-wall which might defy 

 any storms. We mention this as an 

 example of the advantage which may 

 be taken of particular circumstances, 

 by which a great expense may some- 

 times be saved. In other situations, 

 where the shingle is not thrown up, 

 and the wall is not so immediately 

 exposed to the action of the waves, 

 an excellent facing of the wall is made 

 by several rows of piles from five to 

 fifteen feet long, driven along the side 

 of the earthen bank in the form of 

 Bteps rising above each other. These 



piles are driven very close together, 

 and the distance between the rows is 

 about two feet. This interval is filled 

 with stones, and bushes are pinned 

 down over them by means of wooden 

 pins driven horizontally through holes 

 made in the piles. This contrivance 

 effectually prevents the washing away 

 of the bank. 



" Where the land lies very flat for a 

 considerable distance from the sliore, 

 it is of advantage to have two com- 

 plete banks, one within the other, so 

 that if the outer bank is broken 

 through, the second will keep back 

 the waters, until the first can be re- 

 paired. The ground between the two 

 lines of banks is usually left in pas- 

 ture. In this case the damage done 

 by an inundation of salt-water will 

 not be so great as if the land were 

 arable ; and unless it remain flooded 

 for a considerable time, the herbage 

 sutlers little, if anything, from it. 



" The water which accumulates 

 within the banks and is collected in the 

 internal ditch and those which divide 

 the marshes must be let off occasion- 

 ally by means of channels and sluices 

 at the time when the tide is out, and 

 the water outside the bank is lower 

 than that which is within it. In small 

 embankments a wooden trunk or pipe 

 may be laid through the bank, with 

 a valve opening outward, by which 

 means the superfluous water may flow 

 out, and none flow back. It is use- 

 ful to carry this trunk a considerable 

 way outside the bank, if it empties 

 itself immediately into the sea, in or- 

 der that it may not be choked up with 

 sand or shingles. Cast-iron pipes ar6 



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