Abstract: Hydrostatic bearing arrangements in which there is a fluid-flow control valve adapted to exercise an automatic pressure responsive control over two fluid-flow outputs to a pair of bearings. The valve has a diaphragm located between two control surfaces formed by bosses so that a fluid-flow restriction is formed between the diaphragm and each of the control surfaces, whereby movement of the diaphragm in a direction to close one of the restrictions opens the other restriction and vice versa, there being a single fluid supply port opening through one of the control surfaces into the restriction between that surface and the diaphragm and a communicating port through the diaphragm substantially aligned with said inlet port.