<PICT:0761511/IV(a)/1> <PICT:0761511/IV(a)/2> <PICT:0761511/IV(a)/3> <PICT:0761511/IV(a)/4> A number of yarns are processed by bringin them together to form a single bundle, after treating one or more of the ends so as to facilitate their ultimate separation, advancing the bundle along a helical path whilst subjecting it to the desired processing, separating the bundle into its constituent yarns and collecting the separated yarns. The treatment of the yarn ends to facilitate their ultimate separation may consist of imparting a small twist to each yarn before its association into the bundle, or subjecting one or more of the yarns to chemical treatment to alter their cross-section. The process is applicable to all continuous filament yarns including those of natural silk, regenerated cellulose, polyesters, polyamides, polyacrylics and copolymers. It may be applied continuously with the production of artificial silk yarns or as an after-treatment, particularly in melt and dryspinning where the speed of production is too great to permit of processing on threadadvancing devices. Processing which can be effected according to the invention includes applying regenerating or purifying liquids, washing, stretching, bleaching, dyeing, finishing or sizing, and drying. In the production of viscose rayon using an acid coagulating bath, processing according to the invention may include dilute acid regeneration, stretching, washing, desulphurizing, bleaching, oiling and drying. As shown in Fig. 1, three rayon yarns 15, 16, 17 from slowly rotating spinnerets 10, 11, 12 are associated into a bundle 28 which is advanced along successive treating rollers whilst being subject for example to the action of liquids from tubes 40, 41, 42 and to drying by heat from steam circulated in the interior of roller 30. The bundle passes through guide 32 and is then divided into its constituent yarns 15, 16, 17 which are individually wound. Separation into individual threads is facilitated by the small twist imparted by the rotating spinnerets; this may be only 1 turn in 200-600 inches, but is stated to be sufficient upon insertion into the bundle of a sharp-pointed instrument, e.g. a pin, to effect separation, the twist in the yarn passing the pin being caused to "back-up", which results in the filaments of the particular yarn concerned being grouped together. In an alternative method, Fig. 3, two yarns from spinnerets 61, 62 are grouped together, but before their association one yarn is treated with zinc sulphate solution or dilute sulphuric acid applied through tube 68 and excess removed by trough 69. After treatment on rollers 65, 71 and drying on roller 74 the bundle passes through guide 78, is separated into the two yarns which are individually wound. (Only one winding device 80 is shown.) The yarn treated with zinc sulphate or sulphuric acid swells, which facilitates ultimate separation of the two yarns. Application of the zinc sulphate or sulphuric acid is discontinued as soon as the apparatus has been threaded up. Fig. 5 shows a device for facilitating ultimate separation of yarns to which a slight twist has been imparted. In use, the smooth portion 91 of the device is pressed against the travelling yarn bundle, which flattens out and tends to separate into its constituent yarns, the individual yarns then engaging the undulations 93. Should the filaments of different yarns become mixed, the flattening of the bundle and the undulations 93 cause the twist in the yarns concerned to "back up" and effect correct grouping of the filaments. When the yarns are correctly separated they are guided over threaded bar 96. In a modification, Fig. 6, the travelling bundle is first flattened by contact with a smooth arcuate surface 101 and then separated into yarns by the comb member 102 which is pivoted and held in the path of the yarns by a light spring 103. The comb may be manually held clear of the yarns by lever 104.ALSO:<PICT:0761511/IV(b)/1> <PICT:0761511/IV(b)/2> <PICT:0761511/IV(b)/3> <PICT:0761511/IV(b)/4> A number of yarns are processed by bringing them together to form a single bundle, after treating one or more of the ends so as to facilitate their ultimate separation, advancing the bundle along a helical path whilst subjecting it to the desired processing, separating the bundle into its constituent yarns and collecting the separated yarns. The treatment of the yarn ends to facilitate their ultimate separation may consist of imparting a small twist to each yarn before its association into the bundle, or subjecting one or more of the yarns to chemical treatment to alter their cross-section. The process is applicable to all continuous filament yarns including those of natural silk, regenerated cellulose, polyesters, polyamides, polyacrylics and copolymers. It may be applied continuously with the production of artificial silk yarns or as an after treatment; particularly in melt and dry-spinning where the speed of production is too great to permit of processing on thread-advancing devices. Processing which can be effected according to the invention includes applying regenerating or purifying liquids, washing, stretching, bleaching, dyeing, finishing or sizing and drying. In the production of viscose rayon using an acid coagulating bath, processing according to the invention may include dilute acid regeneration, stretching, washing, desulphurizing, bleaching, oiling and drying. As shown in Fig. 1, three rayon yarns 15, 16, 17 from slowly rotating spinnerets 10, 11, 12 are associated into a bundle 28 which is advanced along successive treating rollers whilst being subject for example to the action of liquids from tubes 40, 41, 42 and to drying by heat from steam circulated in the interior of roller 30. The bundle passes through guide 32 and is then divided into its constituent yarns 15, 16, 17 which are individually wound. Separation into individual threads is facilitated by the small twist imparted by the rotating spinnerets; this may be only 1 turn in 200-600 inches, but is stated to be sufficient upon insertion into the bundle of a sharp pointed instrument, e.g. a pin, to effect separation, the twist in the yarn passing the pin being caused to "backup" which results in the filaments of the particular yarn concerned being grouped together. In an alternative method, Fig 3, two yarns from spinnerets 61, 62 are grouped together, but before their association one yarn is treated with zinc sulphate solution or dilute sulphuric acid applied through tube 68 and excess removed by trough 69. After treatment on rollers 65, 71 and drying on roller 74 the bundle passes through guide 78, is separated into the two yarns which are individually wound. (Only one winding device 80 is shown.) The yarn treated with zinc sulphate or sulphuric acid swells, which facilitates ultimate separation of the two yarns. Application of the zinc sulphate or sulphuric acid is discontinued as soon as the apparatus has been threaded up. Fig. 5 shows a device for facilitating ultimate separation of yarns to which a slight twist has been imparted. In use, the smooth portion 91 of the device is pressed against the travelling yarn bundle, which flattens out and tends to separate into its constituent yarns, the individual yarns then engaging the undulations 93. Should the filaments of different yarns become mixed, the flattening of the bundle and the undulations 93 causes the twist in the yarns concerned to "back-up" and effect correct grouping of the filaments. When the yarns are correctly separated they are guided over threaded bar 96. In a modification, Fig. 6, the travelling bundle is first flattened by contact with a smooth arcuate surface 101 and then separated into yarns by the comb member 102 which is pivoted and held in the path of the yarns by a light spring 103. The comb may be manually held clear of the yarns by lever 104.