Abstract: A clothes washing machine is provided with a wash tub (1) and a rotating arm (2) accommodated within the wash tub and adapted to contain washload items and capable of being driven so as to rotate both at high and low rotating speeds. A pressure switch (3) is arranged within an appropriate air chamber connected with the intake thereof at a location (4) situated below the lower level (5) of the wash tub. An inlet and shut-off (6) governs the water supply from the water delivery mains to the wash tub. The inlet and shut-off is arranged to detect average soaking characteristics of the washload items placed in the drum by first measuring their overall capacity of absorbing a defined amount of water, and then processing the measured capacity on the basis of the weight of the washload items, the weight being known.