The underlying substance is Sumerian bitumen: a naturally occurring petroleum material (often called an asphalt-like “black goo”) long associated with waterproofing and adhesion, and even with ...

Sumerians used advanced ancient technology to engineer bitumen with fibers and minerals, revealing sophisticated material science.

Reprint from the Smithsonian report for 1959. https://siris-libraries.si.edu/ipac20/ipac.jsp?&profile=liball&source=~!silibraries&uri=full=3100001~!926647~!0#focus ...