TOBACCO-PIPES are made of clay, white and coloured earths, porcelain, ivory, and various other substances. The tobacco-pipes commonly used in this oountry are formed of a fine plastic white clay, which is called from this application, It is procured chiefly from Purbeck, in Dorsetshire ; and, after being purified and made into a soft state, is cut into small pieces, each enough for one pipe. Each piece is kneaded tho roughly upon a board, and rolled out to nearly the form and size of a pipe, with a pro jecting bulb at one end for the formation of the bowl. These pieces are laid aside for some time to dry, and when the clay is suf ficiently firm, they are subjected to the curious process of baring. The workman takes the roll of clay in his left hand, and with his right inserts the end of an iron needle, previously oiled, in the small end of the roll, and by dexterous management thrusts the needle through the whole length of the roll, without penetrating the surface. The bulb is then bent into the proper position to form the bowl, and the piece of clay, with the needle remaining in it, is pressed into a mould to complete its form. The moulds are made of metal, in two halves. The bowl is partially hollowed by the finger, and completed by the insertion of an oiled stopper or mould. The wires are now withdrawn, and the pipes are taken out of the moulds, slightly smoothed over, and laid aside to dry. After drying for
a day or two, any remaining roughness is re moved by means of an instrument of bone or hard wood, and then the pipes are sometimes moulded a second time, and polished with a piece of flint bored with holes, through which the stem is passed repeatedly. The pipe stems are thus far straight, but before going to the kiln they are slightly bent.
The tobacco-pipe kiln consists of a large hut very light cylindrical crucible, with a dome-shaped top, and a circular opening in one side for the insertion of the pipes. This crucible is mounted in a brick furnace, lined with fire-brick, in such a manner as to leave a space of about four inches all round for the circulation of flame. The pipes are placed in the kiln, with their bowls against the circum ference, and their ends supported at a consi derable elevation upon circular pieces of clay set up in the centre. By this arrangement one furnace may contain fifty gross, or 7,200 pipes, which may all be baked within eight or nine hours.
A different kind of clay or earthen pipe is described under MEERSCHAUM PIPES.
Mr. Skertchley patented a somewhat com plicated machine for making tobacco-pipes, in 1848; and Messrs. Steel and Britten patented another machine for the same purpose in the same year.