Those trades which could not obtain the protection of monopoly attempted to protect themselves when possible by trade secrets. This was a much more important protection in those days than it would be now. Combinations and processes, tricks of the trade which had been discovered experimentally by some clever workman, could hardly be discovered by his rivals unless they could hit upon the same thing by a tedious course of experimentation or could in some way secure betrayal of the secret. Very few trade secrets can be hidden from modern science, but modern science did not exist in the fifteenth century. The apprentice was sworn not to betray his master’s secrets, and the consequences of such betrayal were very serious. As we have already seen, Gutenberg at first attempted to keep printing a trade secret, but the obvious impossibility of doing so led to other methods of protection. Fortunately for the new art the great men of the time were interested in it and, as a rule, it was not difficult to obtain a certain amount of protection by privilege. Venice was perhaps the most advanced state in Europe in the middle of the fifteenth century, certainly it was one of the most advanced. The intelligent business men and astute nobles trained in public affairs who made up the body of citizens of the Republic of Venice were not slow in perceiving that a condition had arisen which must be immediately attended to. The matter was therefore taken up by the Council of Ten, an executive body which had large functions in the government of Venice. Their methods of dealing with the matter may be divided into four heads. The first was the monopoly under which only one printer was allowed to work in a given town. Such a monopoly was granted John of Spire who, in 1469, was given the sole privilege of doing printing in Venice. Fortunately the unwisdom of this particular method of protection was soon seen and other printers were allowed in Venice. The next was a form of privilege something like the modern copyright. Under this a publisher or even an author was granted the sole right to print or cause to be printed a certain book. The first one of these copyrights was issued to Antonio Sabellico in 1486. Sabellico was the official historian of Venice and the copyright covered his history. Unlike modern copyrights, which cover but a single book, these privileges might cover anything that an author had written or might write. It is clear that such a blanket copyright in the hands of a publisher might be used very injuriously, and there is evidence that they were so used either to extort money or to impede publication. It is probable that in many cases this form of privilege involved some arrangement between the author and the printer whereby the author shared the profits.