Bitumen

Bitumen is a natural mineral pitch or asphalt found in deposits throughout the ancient Near East, particularly in the region around the Dead Sea and in Mesopotamia. The Hebrew word chemar, translated as slime in the Authorized Version and bitumen in the Revised Version, refers to this sticky, waterproofing substance. The Valley of Siddim near the Dead Sea was full of slime pits—bitumen deposits—which the kings of Sodom and Gomorrah fell into when their forces were routed by the four eastern kings.

Bitumen served two crucial functions in biblical narrative. Noah's ark was pitched—waterproofed—inside and out with pitch (kopher), a related substance. The basket of papyrus reeds in which Moses's mother concealed her infant son on the Nile was similarly daubed with bitumen and pitch to make it watertight. In both cases, a humble waterproofing material becomes the means of preserving life in a life-threatening situation involving water. Bitumen was also extensively used in Babylonian construction, where it served as mortar for the great ziggurats and city walls—the context in which Genesis 11:3 mentions it for the Tower of Babel.