Coal was one of man's earliest sources of heat and light.  The Chinese were known to have used it more than 3,000 years ago.  The first recorded discovery of coal in this country was by French explorers on the Illinois River in 1679, and the earliest recorded commercial mining occurred near Richmond, Virginia, in 1748.  On April 13, 1750, Dr. Thomas Walker was the first recorded person to discover and use coal in Kentucky.