Abstract: A sprinkler having a body with a smooth annular interior surface which converges in a downstream direction to a throat and then diverges to a generally conical depression, the interior surface being fair at the location of the throat to reduce turbulence, the water entering the throat being rotationally swirled by some swirl imparting surfaces upstream of the throat, and the depression containing an impeller which has a conical surface which lies contiguous with the conical surface of the depression, but the conical impeller surface is interrupted and contains discharge channels extending outwardly from near the center of the impeller.

Abstract: The marine hull has a forebody, a transom, and a bottom extending therebetween having pairs of upwardly formed channels between the forebody and the transom. The channels of each pair diverge rearwardly. Fluid flow exit paths interrupt the channel walls so that fluid from some of the channels can flow laterally outwardly, and the rear ends of at least some of the channels open at a peripheral edge of the bottom whereby water in these channels is free to discharge in both a rearward and laterally outward direction.

Abstract: A marine hull including a plurality of channels extending rearwardly and inclined, in plan, with respect to the central longitudinal vertical plane of the hull, the cross-sectional shape of each channel being curved so that its surface intercepts water when the hull is mobile and that water is caused to leave each channel in a downward direction thereby imparting lift over a major portion of the length of the hull.

Abstract: A servo controlled vehicle suspension which will reduce the dynamic forces imparted to the relatively high inertia structure when the relatively low inertia structure moves, as for example when the wheel of a motor vehicle encounters a bump or dip in a road. The suspension includes resilient sensing device, a pump and a valve, the valve being controlled by the sensing device to deliver oil from the pump to a chamber which expands as the low inertia structure (the wheel) moves downwardly when a dip is encountered, the valve however being controlled to open a drain port to allow oil contained in the chamber to discharge to drain with relatively little resistance when the low inertia structure encounters a bump, the arrangement being such as to reduce the variation in force between the structures.