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 XXV

Caxton, 1482.

two rival printing offices had been established at Mentz it was no longer possible to keep secret the processes. Every printer who handled the types and every goldsmith who helped to make the tools must have felt a weakening of the obligation of secrecy. The sack of Mentz was a greater misfortune, for it dissolved all obligations and sent the printers to other cities to found new offices. Not one of these printers has told us when and how he began to print on his own account. All we know about the introduction of printing in many of the large cities has been gathered from the dates of books and the chance allusions of early chroniclers. It is from these imperfect evidences