Oiled Lines
Early braided silk lines were filled with linseed, or some other oil, to give them weight and to make them waterproof. Some anglers still use the oiled lines but mainly for economy as they are inferior to the enameled.
Hard Enameled Lines
I believe the process of enameling a line is of American origin; anyway American hard enameled lines were for many years the world's standard of excellence.
They are usually made of a good grade of Italian or Japanese silk, hard braided, and finished by a process that is more or less of a trade secret. It may be said generally that the best American hard enameled lines combine good weight, beautiful finish, flexibility, with just enough stiffness to cast well, and extraordinary wearing qualities. These lines range in price from three to ten cents a yard, depending on quality and taper, and are usually sold on cards holding twenty-five or thirty yards. They come in a variety of colors, a popular one being the so-called " mist" or " water " tint,— a sort of green-gray.