Abstract: A human-powered pump assembly includes a frame and a treadle pivot attached to the frame, such that the treadle pivot defines a horizontal rotational axis. The pump assembly includes a pair of treadles coupled to the treadle pivot and a rocker pivot attached to the frame, such that the rocker pivot defines a separate horizontal rotational axis. The pump assembly includes a reciprocating rocker coupled to the rocker pivot and to the pair of treadles to constrain the motion thereof, such that the rocker pivot axis is located below the treadle pivot axis.

Abstract: The present invention relates to an improved subsea wellhead structure which includes a conductor casing having an internal upwardly facing shoulder, and an internal groove above the shoulder, an external groove, a wellhead housing having an external downwardly facing shoulder adapted to seat on the casing shoulder, an external shoulder above the seat shoulder which tapers upwardly and outwardly at a slight angle, such as, for example, five degrees, a split latching and loading ring surrounding said housing and seated on said tapered external shoulder, a cam ring above the split ring, means for releasably retaining the cam ring in its inactive position and actuating means for moving the cam ring into position wedging the split ring outwardly on the tapered shoulder into tight load transmitting position within the internal casing groove and the tapered shoulder.