are provided the needle butts 19 are normally arranged in a non knit track 25 plush fabric or tuck track fur fabric the jack butts 23 being arrranged in a jack track 29 because of the influence of a spring 27 located in the base of the tricks every jack is associated with a control spring 31 attached to the needle cylinder this spring being subject to the influence of the patterning mechanism 11 every time it passes it such that the jack butt 23 of the relevant jack either remains in the jack track 29 and is then raised by a raising cam 33 or is removed from the jack track 29 by the tilting of the jack as a result of which it slides behind the raising cam 33 such patterning and selection mechanisms are clearly described in u s pat no 3 449 928 and in u s pat no 3 898 818 to schmidt to which reference is made to avoid unnecessary repetition the butts 19 of those knitting needles corresponding to a jack raised by the raising cam 33 are raised by the jack on to the laying in cam segment 13 this segment 13 is located at a height such that into the hooks of a knitting needle passing by it can be fed the fibers from a sliver delivered from a doffer 35 or the pile thread supplied from a thread feeder details of this process are known from the abovementioned specifications and therefore require no repetition at.