Tar

a dark, sticky liquid variously obtained by destructive distillation. The wood tar of the United States is produced chiefly in the southern Atlantic States from the long-leafed pine by a very crude method. A conical chamber or cave is excavated in the side of a steep bank. A large sheetiron pan is placed in the bottom, provided with a spout leading into a barrel outside. The cave is filled with logs of pine, and the face built up with sods to prevent the entrance of air. The mass of wood is then fired. It burns slowly without a flame, and literally roasts the tar out of the wood. The tar is caught in the pan, and trickles slowly out into the barrel. When one barrel is filled, another is put in its place. Wood tar is in use for tarring ropes, and covering timbers exposed to the weather. Tar is a cure for certain diseases of the skin. It is used in making tar soap and in compounding tar remedies for lung troubles. Charleston, South Carolina, Archangel, Russia, and Stockholm, Sweden, are noted centers of the tar trade. Coal tar is obtained--ten gallons to the ton--by a somewhat similar process of roasting coal in the manufacture of illuminating gas. It is used for preserving timber and in making tar paper. Coal tar also makes an excellent protective paint and, being waterproof, is much used in laying gravel roofs. Coal tar yields the oil known as benzine. It is the base also of the beautiful aniline colors now the dependence of the dyer's art. Owners of gasworks formerly considered coal tar an expensive nuisance. They now regard it as a by-product of substantial value. See Turpentine; Aniline