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road of New Jersey. When built by contract these sod dikes cost 

 less than 25 cents per lineal foot. 



This diagram (Fig. 2) is to illustrate how the dikes are con- 

 structed to prevent the water at high tide from overflowing- the 

 meadows. The water in the creek at the left is shown at low- 

 tide level, and mean tide, or sea level, and high-tide and storm- 

 tide levels are indicated. The dike, which is of the sod type, is 

 made in three layers, and the material for its construction is dug 

 from the ditch shown to the right. The meadow surface between 

 the dike and the creek, called the foreshore, is not protected 

 from overflow at high tide, but it is narrow enough to drain off at 

 low tide to prevent the growth of mosquitoes. The ditch to the 

 right is connected on one side with the small ten-inch ditches, 

 and on the other side with the sluiceways^ with tide-gates pass- 

 ing under the dike to the creek. 



This illustration (Fig. 3) shows a completed sod dike in the 

 Union County portion of the area just described. It is 6 feet 

 wide at the base and 2 feet wide at the top and 3 feet high. 

 The high grass along the side, of the dike conceals about one foot 

 of its height. , 1 



The first process in the construction of a sod dike is to dig 

 a ditch 10 inches wide along the center line of the proposed 

 dike. This is to remove the sod and make room for a mud core 

 which is used to make the dike water-tight. Two men operate 

 the spade which digs this ditch, while a third assists by prevent- 

 ing the sod from slipping off the spade while it is being brought 

 up from the ditch. (Fig. 4.) 



This illustration (Fig. 5) shows the construction of the first 

 tier of the dike, and shows how the material is taken from the 

 ditch made parallel to the dike. 



This illustration (Fig. 6) shows the construction of the second 

 tier. 



This illustration (Fig. 7) shows how the mud core is rammed 

 down to make the dike water-tight. This is done before the top 

 layer is put in place. 



This is another view of a completed dike. (Fig. 8.) In the 

 construction the grass ends of the sods are turned outward, and 



