is reduced by an amount of volume corresponding to the total volume of the protrusions application_number US 25357588 A description referring now to the drawings wherein like reference numerals are used throughout the various views to designate like parts and more particularly to fig2 according to this figure a dehydrating tub in accordance with the present invention may be employed in for example a fully automatic washing machine including a timer 1 for controlling the washing machine a lid 2 upwardly openable about a pivot axis 3 a communicating tube 3 communicating with a connecting portion of a water supplying tube not shown and a water supplying portion 22 a dehydrating tub 8 and an outer tub 14 an opening 6 is provided for enabling a load of wash to be placed in the washing machine with a cover 7 being provided on an upper portion of the outer tub 14 for preventing the wash from falling between the dehydrating tub 8 and the outer tub 14 a plurality of dehydrating ports 9 discharge water during dehydration and are formed in a plurality of vertically extending valley grooves 17 formed in a wall surface of the dehydrating tub 8 a balance ring 10 enables a smooth rotation of the dehydrating tub 8 upon a dehydrating operation of the washing machine an agitator 11 disposed in the dehydrating tub 8 with the agitator 11 including a main blade 12 small blades 13 and a cap 21 the washing machine further.