It is not long since it was commonly thought that the art of blowing glass was known for several thousand years before Christ. Certain Egyptian tomb-paintings of the twelfth dynasty (c. 2OOO b.c.) and later, which really depict metal-workers blowing the flames of their furnace, were thought to represent glass-blowers. As a corollary, it has been said that not a few of the vessels of blown glass found on ancient sites in Greece and other Mediterranean countries belong to the Greek period. Such beliefs are quite incorrect. There is no evidence that the process of blowing glass was invented until about the time of Christ. Scientific excavation in Greece has proved beyond question that any fragments of glass vessels found there belong to Roman or later times; the tombs in Cyprus that contain Hellenistic or earlier pottery contain no blown glass, whereas in tombs of Roman date blown glass tends to displace pottery as funerary furniture; and similar observations have been made during scientific excavations in the other Mediterranean countries.