Abstract: To impregnate loose cotton staple and like fibers with chemicals, a mass of such fibers is fed into and through a series of compartments in a baffled housing assembly and is there acted upon by a series of cooperating rotating paddle assemblies while in contact with a chemical containing aqueous liquor at room temperature and atmospheric pressure. The paddle assembly initially produces, with the liquid, turbulent columns of bubbles within each of the compartments, with the result that the cotton fibers are located in the thin walls between the bubbles.