12 August 1966
Vol 153, Issue 3737

About The Cover

Cross section of a coal mine in South China in the 17th century. Because of the denger of gases, the miners were attached to winches by a safety line, and attempts were made to pipe out the ges with bamboo shafts. The drawing, slightly modified, is interesting as an early cutaway diagram, but the pipe and which shown are probably based on hearsay rather then observation.See review of T'ien-Kung K'ai-Wu. Chinese Technology in the Seventeenth Century, page 730.[Pennsylvania State University Prss]