50 for use in securing the two members 50 and 51 together by means of a plurality of bolts 58 as shown in fig3 the base 57 of top member 51 defines a top wall portion spaced apart from a bottom wall portion provided by the base 54 bottom member 50 the base 57 of member 51 has a plurality of flow ports 59 therein arranged in a row and providing flow communication between the upper portion of the cartridge 40 and the internal cartridge chamber 42 which is defined by the inwardly facing surfaces of bases 54 and 57 and legs 53 a nozzle strip 60 is adapted to be positioned at the lower end of cartridge chamber 42 adjacent base 54 providing the bottom wall of the cartridge 40 nozzle strip 60 is supported between the upper surface of the base 54 of bottom member 50 and the lower ends of the legs 53 of top member 51 as is apparent from a consideration of the drawings nozzle strip 60 has a plurality of orifices 62 therein spaced apart along the length thereof and arranged in a row to be aligned with the cartridge slot 46 as is shown in the drawings the orifices 62 are constructed and arranged so as to provide concentrated jets of liquid and to discharge them in the curtain like array of water streams 14 as shown in fig1 cartridge 40 comprises means to provide a seal between the downstream surface of.