In this class, the following terms are used with the meanings indicated: "fibre" means a relatively-short, elongated member of natural or artificial material; "filament" means an endless or quasi-endless, elongated member of natural or artificial material; "yarn" means a unitary assembly of fibres, usually produced by spinning; "thread" means an assembly of yarns or filaments, usually produced by twisting. Attention is drawn to the Note following the title of class . TREATMENT OF PLANT MATERIAL Separation of fibres from plant material Hackling or heckling machines TREATMENT OF ANIMAL FIBRES De-burring, washing, scouring Obtaining silk fibres OTHER TREATMENTS Attention is drawn to the Note following the title of class . Processes using enzymes or micro-organisms in order to: liberate, separate or purify a pre-existing compound or composition, or to treat textiles or clean solid surfaces of materials are further classified in subclass . Attention is drawn to the Note following the title of class . Apparatus specially adapted for the manufacture of carbon filaments are classified in group . MECHANICAL TREATMENT OF FILAMENT-FORMING MATERIAL PRODUCTION OF ARTIFICIAL FIBRES Methods Spinnerette packs; formation of filaments; collecting the newly-spun products ; ; Physical treatment during manufacture Other operations COMPLETE MACHINES; DETAILS ; , , Attention is drawn to the Note following the title of class . Processes using enzymes or micro-organisms in order to: liberate, separate or purify a pre-existing compound or composition, or to treat textiles or clean solid surfaces of materials are further classified in subclass . GENERAL PROCESSES FILAMENTS AND MANUFACTURE THEREOF From cellulose or derivatives; from proteins ; From synthetic resins From other materials Multicomponent filaments AFTER-TREATMENT; RECOVERY OF STARTING MATERIAL ; Attention is drawn to the Note following the title of class . OPERATIONS BEFORE CARDING; MACHINES THEREFOR Opening fibre bales; separating and sorting of fibres; opening or cleaning fibres ; ; Severing of continuous filaments; roughening of fibres ; Recovery of fibres by breaking-up fibre-containing articles Mixing of fibres, or of fibres with non-fibrous materials CARDING OR SUBSEQUENT OPERATIONS; MACHINES THEREFOR Feeding or conveying fibres for machines; lap-forming; lap-winding; lubricating fibres ; ; ; Carding and burr-crushing, combing , SILK-DRESSING; TREATMENT OF OAKUM ; COMBINATION OF MACHINES OR PROCESSES FOR CONTINUOUS PROCESSING WARNING OR SAFETY DEVICES HAND TOOLS FOR TREATMENT OF FIBRES OTHER PRELIMINARY TREATMENTS Attention is drawn to the Note following the title of class . SPINNING OR TWISTING MACHINES With continuous wind-up; with intermittent wind-up ; Open-end spinning Drafting machines or arrangements Spinning or twisting arrangements COMMON STRUCTURAL FEATURES, DETAILS, OR ACCESSORIES Replacing bobbins; confining or removing dust or fly ; Other structural features, details, or accessories Piecing arrangements; hand tools ;