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TIDAL LAND RECLAMATION
   On the Dutch coast practice differs considerably from the English. The Dutch seaboard for the most part consists of wide sandy plateaux, lying at an easy gradient, and the problem is to check the scend of the water, the momentum of the waves being largely absorbed by the flat foreshore. The difficulty in many Dutch undertakings is the precarious nature of the foundations of sea-walls. Many miles of sea-walling in Holland rest upon unstable clay embankments, and the result is frequent casualties, called “falls”. If by underwater denudation the sea front becomes mobile, the earth pressure at half-flood sets the mass of the wall in motion. It thus happens that large areas, sometimes amounting to hundreds of acres, slide bodily down into the bed of the sea. These casualties resemble the effect of earthquake shock, and are followed by a great tidal wave sweeping landwards, and thus completing the devastation of the polder in rear of the sea-wall.
   The standard Dutch practice has hitherto been the use of basalt stone facing. This was brought down the Rhine from the Andernach district. Formerly a limestone from Dornik was used. The cost of facing Dutch dams was about i6j. per square yard, the basalt representing about 9s. 9d. of this sum. The method usually adopted is as follows:—
   The slope of the wall is carefully graded with clay to leave a finished surface. This surface is then thatched with straw or rushes, and the workman forces the sheaves of straw into the clay up and down the wall and at right angles to it. The covering of straw or rushes is about 1 inch thick, and a labourer will lay 70 yards in a day, the cost of which is slightly over 2d. per square yard. Over the straw brick tiling 2 inches thick is laid; above the tiling random broken brick, and the surface is formed of basalt pitching 15 or 16 inches thick, packed with brick. It will be seen that the art of the sea-waller in Holland is highly expert. The sums expended are extreme. On the Osse breakwater, in the Island of Schouwen, the cost of the basalt pitching was £3. 12J. per lineal foot.
   In the Dutch practice matting or fascine work is largely employed. In the lightest matting branches of willow 10 to 12 feet long, freshly cut, are laid on the slope to be protected,