The Greek letters were used by the Druids for keeping the public or private records, the only matters which they reduced to writing. The Druid schools and seminaries were held in the caves such as we have already described, or in the recesses of the sacred groves and forests of Britain. The most eminent academy is said to have been in the Isle of Anglesey, near the residence of the Arch-Druid; and there are still two spots there called "the Place of Studies," and "the Astronomer's Circle." The British youth, separated from their parents, were under Druidical instruction until they were fourteen, and no one was capable of a public employment who had not been educated by a Druid. The Roman invasion, however, greatly improved the Druidical plan of instruction; since Julius Agricola was careful that the sons of the principal Britons should be taught the liberal sciences. His endeavours were considerably assisted by the expulsion of the Druids, which took place about this period; and also by the ability of the British youth, whom he declared to excel the Roman. The ranks of the priests were recruited from the noblest families of the early Britons: their education, which often extended over a period of twenty years, comprehended the whole sciences of the age; and beside their sacred calling, they were invested with power to decide civil disputes. Their dwellings and temples were situated in the thickest oak groves, which were sacred to the Supreme Deity. No sculptured stones or storied bricks have ever been found of this period; nothing but weapons of stone, of bronze, and lastly, of iron, remain to attest the slow progress of a rude people towards a higher stage of civilization, in the arts relating to the chase and to war. As the Gauls used to ornament their shields and helmets with brass images of animals and horns, it is not improbable that some rude endeavour decorated the armour of the Britons. Whatever their skill might be, it was, doubtless, greatly improved by the Romans, since their bas-reliefs and effigies have been found in different parts of the kingdom; and as early as A.D. 61, not twenty years after the invasion of Claudius Cæsar, a statue of Liberty was erected at Camulodunum, or Colchester. The early custom of painting the body has been incidentally mentioned. The Southern Britons stained their bodies with woad, deep blue, or a general tint; the Northern Britons added something of design by tracing upon their limbs figures of herbs, flowers, and trees, and all kinds of animals. It is doubtful whether in these arts they were improved by the Romans; since the delineation of deities, which Gildas mentions, on the walls of the British houses, are said by him only to resemble demons.