Glass molding and glass blowing existed side by side in a Jerusalem glass factory during the Herodian period. Here we see the refuse from this factory—evidence of an industry in transition. The Upper City excavations present archaeologists and ancient glass experts with a unique opportunity to study a pivotal phase in the history of glass manufacture.

Found among the refuse were broken bowls; chunks of unprocessed glass; a heap of stems and pipes; a striped blowing pipe and fragments of a flask blown from it (reassembled in an artist’s reconstruction); mouth and neck fragments of flasks; and pipes broken just as egg-shaped globs of glass were being blown.

Before these pipes were discovered, scholars thought that glass vessels were blown from glass globs at the ends of metal pipes, but these finds show that in the earliest stage of glass blowing, the globs of hot soft glass were stuck onto pipes that were themselves made of glass.

Below are fragments of glass bowls that were molded, not blown. Simple concentric circles are incised along the inside of their rims. Alongside the fragments an artist has shown what complete bowls would look like, as projected from the shape and design of each fragment. The top bowl is rounded and the bottom bowl has a ribbed body and is carinated—sharply angled just under the shoulder.