Nay, _ostrakon_, the common word for a potsherd, familiar to us from its famous derivative Ostracism, or _Voting by Potsherds_, so called because the people inscribed their votes on pieces of pottery, meant originally nothing more than an oyster shell. In Latin _testa_, the ordinary name for an earthenware vessel, means nothing more than the covering of a shell-fish, and from this word _testudo_, the Latin name for the tortoise, is simply a derivative. Such instances could be multiplied if it were necessary, but those mentioned are sufficient to show the high probability of so valuable a shell as that of the tortoise having been employed. Owing to its beauty it would probably hold its place in Greece as the choicest kind of vessel for centuries after the art of pottery was known, just as it did in Cochin China. It would be only when the art of glazing and embellishing pottery had made some progress that vessels of baked clay could compete with the lustrous, many-hued shell. Nor are we without some direct evidence for the use of tortoise shell among the Greeks. The famous story of the invention of the lyre by the god Hermes is not without significance. According to the Hymn to Hermes, “the precocious divinity on the very day of his birth sallied forth and found a tortoise feeding on the luxuriant grass in front of the palace, as it moved with straddling gait.” His eye was caught by the dappled shell (αἰόλον ὄστρακον), and carrying home his spoil, he made of it a lyre. The legend which thus explains why the sounding-board of the lyre is so called points back to a time when the best form of bowl or hollow vessel for making a sounding board for a musical instrument was that afforded by the shell which was probably one of the common articles of everyday life.