a dispenser that incorporates the alternative enclosure the alternative enclosure is filled with a fragranced surfactant solution through the liquid inlet tube 40 which forces the closed end of the sock 42 from the upper end of the cylinder 36 towards the lower end of the cylinder when the dispenser is subjected to hydrostatic pressure the closed end of the sock 42 is forced from the lower end of the cylinder 36 towards the upper end of the cylinder expelling the fragranced surfactant solution from the cylinder through the liquid inlet tube 40 the lower end of the cylinder 36 is fitted with a circular plug comprising a lower disc 46 and an upper disc 48 the lower and upper discs being attached to one another and separated by a small distance by pegs the upper disc 48 has a central hole 50 such that when the lower disc rests upon the bottom of a lavatory cistern water can enter the cylinder 36 between the upper and lower discs and through the hole 50 in the upper disc so as to subject the sock 42 to hydrostatic pressure and cause the fragranced surfactant solution to be expelled from upper end of the cylinder through the liquid inlet tube 40 fig1 and 11 show an alternative valve denoted generally by reference numeral 78 the valve 78 comprises a generally triangular envelope formed from first and second generally triangular polyethylene sheets 80 and 82 that are welded along two of each of their sides so as to form first and second seams 84 and 86 respectively and a polypropylene.