Improved chemical adhesive systems developed in the late 1920s and early '30s by E.I. Du Pont and others, enabled use of stronger synthetic cord to replace the staple cotton found in earlier tires.

Wheel, c. 3500 B.C. Evidence of its use is seen in remnants of the ancient Sumerian city of Ur, once located in what now is southern Iraq. Early wheels were made from two or three segments of wood ...