Abstract: An apparatus for forming embankments comprising a trapezium-shaped shield open at top and bottom and rearwardly. Material for the embankment is introduced into the top of the shield in slurry form and the difference in level between the slurry contained by the shield and the water outside the shield results in a force on the end wall of the shield. This causes the shield to travel end-wall first along the surface on which it is supported. As it moves forward, the shield will leave behind it an embankment formed to the same trapezium-shape as the shield itself. So that a layered form of embankment may be constructed, the shield may be fitted with a number of hoppers each associated with the formation of a particular layer.

Abstract: A device for extracting energy from water waves comprises high-level and low-level reservoirs with non-return valves for permitting water from wave crests to enter the high-level reservoir (but not return) and for permitting water from the low-level reservoir to escape as a water wave trough passes but preventing entry of water from the crests into the low-level reservoir. The non-return valves operate over a vertical extent and are such as to accommodate the variation in time with depth at which water pressure changes from high on one side and low the other to low on the one side and high on the other.