for the office, and large numbers were sent by their parents to undergo the training which sometimes lasted twenty years.[83] The students learnt by heart a great many verses, which were not written down, for this they did not consider right (_fas_), though for secular purposes they used Greek letters. Examples of this writing have been preserved.[84] The Druids taught the doctrine of immortality and the transmigration of souls.[85] Astronomy, physical science, and theology also formed part of their training.[86] Science was still studied by the Druids in Cicero’s time. ‘In Gaul too’ (he says), ‘there are Druids (and I had personal acquaintance with one of them, the Aeduan Divitiacus) who professed a knowledge of natural science, which the Greeks call φυσιολογία.’[87] This education, however, was purely one of class and profession. ‘Docent multa nobilissimos gentis’, says Mela.[88] Lucan apostrophizes the Druids, as those who alone had the privilege of knowing or not knowing the gods, dwelling in the sequestered glades of deep forests.[89] Knowledge, thus monopolized, must have grown unhealthy, and we hear of the riddling speech and obscure phrases with which the Druids worked on the superstitions of the people.[90] Monnard observes that the darkness of this Celtic philosophy was dispelled by the light of Massilia.[91] Yet the Celts had made their contribution. For we must remember that in the centuries just preceding the Christian era it was the Celts who gave the lead to the Teutonic peoples in culture. Towards the end of the fifth century B.C. Celtic civilization flourished exceedingly. The ‘La Tène Civilization’—as the archaeologists call it—shows artistic products of fine taste and technical perfection. The centre of this civilization was perhaps in Southern France, whence it spread throughout Europe along the Rhine, the Rhone, the Danube, until it was succeeded by Graeco-Roman culture. And it was only between 100-70 B.C. that the Celts were expelled from lower Germany.[92]