The 248 quicksilver mine is in Section 248, Block G-4, 2 miles east of Terlingua and 86 miles by dirt road from Alpine, Tex., the nearest railway shipping point (see accompanying maps). Cinnabar, the quicksilver mineral, was discovered before 1902. By 1934 there were only about 700 feet of subsurface workings, but in recent years the Esperado Mining Co., which has the property under lease, has greatly extended exploratory workings and has built a Herreshoff furnace rated at 40 tons per day. At the present time there are 1 1/3 miles of underground workings and 800 feet of surface trenches.