312 Agricultural Notes on Hertfordshire. 
natural or available grass-land. The remedy is simple. The 
mill-dams are impediments to the free action of the landowners, 
but very generally this difficulty may be overcome. The wet- 
ness of the meadows is not, even near the mill-heads, due to 
soakage from the river, but from stagnation in the soil pi water 
derived from springs on either side of the valleys. As a remedy, 
first a ditch should be cut as near to the side of the valley and as 
far lrom the river as possible. In some cases pipes of large bore 
might be used ; the spring-water should then be led below the 
outfall provided by the next mill-dam ; the cleansing of the 
ditches, brick-rubbish, or any hard material, should be placed or 
even piled on the surface of the meadows ; then with ordinary 
attention to keeping up the river-banks and filling up all trans- 
verse ditches, much valuable land might be reclaimed from its 
virtual sterility. 
Water-Cresses. 
A new rival to the water-meadow has sprung up of late from 
the artificial culture of water-cresses. Fifty years ago those who 
sold this plant were content " to strip the brook with mantling 
cresses spread." One such was Mr. Bradbury, to whom the 
idea suggested itself that water-cresses might be cultivated to 
advantage. He obtained permission first to try the experiment 
in spring-ditches at West Hyde, in the parish of Rickmans- 
worth, just on the borders of Bucks, and satisfied the occupier 
of the land that the cleansing of the ditches and regulation of the 
height of the water in them as practised by Mr. Bradbury was 
beneficial. The ditches were next let at a certain rent and under 
certain restrictions, and very shortly Bradbury's cultivated water- 
cresses became a regular article of traffic in the London market. 
From this small beginning a large trade has sprung up, which 
now extends to the Manufacturing Districts. The persons who 
hire the spring-ditches for the cultivation of the plant scour and 
cleanse them with much care, level their bottoms, and often 
expand their area till they form a series of shallow lakes, in 
which the height of the water is regulated by dams. These 
dams are either permanent — formed of stones or two lines of 
boards, supported by stakes, between which clay is rammed ; or 
temporary — consisting of moveable boards, bricks, or other ma- 
terials. These, in some cases, are either placed transversely to 
the flow of the water, to keep it to its required level in the sub- 
divisions of the beds, or eLse so arranged that the stream may be 
conducted under the bank-side, apart from the adjacent bed, 
as by an irrigation-carrier, to any sj>ot below. Very fre- 
quently borings are made in the chalk to facilitate the issue of 
the clear spring-water in its purity, which is deemed of great 
