no THE MAKING OF NEW LAND 



At high tide the sluices are opened, and the thick 

 muddy estuarine water pours up the channel and 

 floods over the embanked area, where it is left to stand 

 for three or four hours until the tide has fallen, when 

 the sluices can be opened once more to allow the water 

 to run back into the open river. Meantime while at 

 rest the water has deposited a portion at least of its 

 burden of silt, and there is left upon the excavated 

 peat a paper-thin layer of fine sand and mud. Tide 

 after tide this process is repeated, the strong springs 

 carry more silt than the slower moving neaps ; but, as 

 a rule, in three years about four feet of soil can thus 

 be built up. Formerly only the summer tides were 

 used, but warping is now carried on all the year round. 

 The surface must be actually dried between tides, and 

 to form a good deposit the water has to be admitted 

 in such a fashion as to cover the whole area as rapidly 

 as possible, to which end the inlets are moved from 

 time to time, because near them the coarser sand alone 

 is deposited, the finer particles being carried farther 

 into the quieter bays of the artificial lagoon. During 

 the process of warping, the sloppy surface which is 

 drowned twice a day becomes a favourite haunt of 

 wild-fowl, and carries a strange vegetation, in which 

 plants of the slob land, like the sea aster and the 

 sapphire, grow luxuriantly side by side with heather 

 and fern still flourishing on little floating islands of 

 peat that have broken away from their foundations and 

 keep rising and falling with the waters. Finally, when 

 sufficient deposit has accumulated, it is given a little 

 time to dry and a shower of rain to wash out the salt, 

 whereupon it is sown with clover and rye grass, which 

 are left down for two years while the ground con- 

 solidates. It is then firm enough to be drained and 

 receive a little levelling in places where deposition has 



