(57) The invention concerns a method of continuously applying a liquor to an elongate material, which comprises forming a linear assembly comprising a plurality of yams, filaments, tow, threads or twines, hereinafter referred to as "linear assembly", continuously feeding liquor to said linear assembly whereby to impregnate said linear assembly with said liquor, characterised in that said liquor/linear assembly combination is continuously passed through an elongate treatment zone and through at least one constrictive throat located in said elongate treatment zone, the at least one said constrictive throat having a cross-sectional area smaller than that of the linear assembly immediately prior to its passage through said at least one constrictive throat such that said linear assembly is compacted on passage through said at least one constrictive throat, and wherein, after passage through said at least one constrictive throat, said liquor/ linear assembly combination passes through a region in which it is maintained in a uniform, composite state. The invention also includes an apparatus for carrying out the said method.