Abstract: A control arrangement, especially for use with a track supported implement, having an elongated beam with carriages at the opposite ends supported on respective tracks in which pick-up elements on at least one of the carriages are sensitive to movement of the respective carriage in a horizontal plane and about a vertical axis on the respective track. The pick-up elements are longitudinally spaced on the curve and supply respective signals to a comparator which emits a control signal which varies as the difference between the pick-up signals varies. The control signal is employed for developing an influence on the beam tending to restore it to the condition of parallelism with itself.

Abstract: An off-shore drilling platform structure and method of mounting in which the structure comprises a base with spaced upstanding legs thereon and a floatable platform slidable along the legs. Laminated tension elements have the opposite ends connected to the base and the upper ends of the legs and the platform has clamp devices for clampingly engaging the laminated tension elements. One clamp device pertaining to each element is nonmovable in the direction of the legs on the platform while the other is movable on the platform in the direction of the length of the legs by power operated devices. The clamp devices pertaining to each tension element are selectively operable so the platform can be moved along the legs.