treatment zone a pressurized liquid is supplied to the conduit when the gas source is disconnected the liquid is directed forcefully from the orifice into the yarn treatment zone to remove deposits which form during treatment of the yarns application_number US 26706188 A description referring now to the drawings in which like reference characters designate like or corresponding parts in fig1 and 2 fig1 illustrates a preferred embodiment of apparatus 10 for the gas jet treatment of moving continuous multifilament yarns in accordance with the present invention apparatus 10 includes a gas jet device 12 which provides interlacing to the four yarn threadlines 14 originating at spinning equipment not shown and being conveyed through the gas jet device 12 subsequent to interlacing the yarns are wound onto bobbins not shown the gas jet device 12 provides a yarn treatment zone for each threadline in which a stream of gas such as air is employed to effect a controlled degree of entanglement or interlacing of the yarns as it moves through the zone the gas jet device 12 depicted is of the type disclosed in u s pat reissue no 29 285 and u s pat no 3 115 691 which are incorporated herein by reference as in u s pat re no 29 285 the yarn treatment zones are within slots provided by the facing surfaces of stacked ceramic plates 34 tombstones 34 16 which are mounted in a spaced apart parallel arrangement on a base 18 and the yarns run through the slots for interlacing as is illustrated in fig2 two orifices 20 in one side surface of the plates 16 provide converging streams of air directed towards the yarn in a slot the orifices are supplied with compressed air from compressed air source.