The florin of Plantin’s catalogue was the equivalent of about forty cents. The average discount given by him to his book-selling customers was fifteen per cent. The agent in charge of the Paris branch received forty per cent. In 1579, Plantin consigned to the Fair at Frankfort 5212 copies of sixty-seven works. During 1570, he sent to his Paris agent books to the value of 19,000 florins. Perez, of Salamanca, was his agent for Spain, where a branch office was carried on at first for the account of the Antwerp concern, and, later, as an independent House. The annual sales through Salamanca of the Plantin publications ranged from 5000 florins to 15,000 florins. In 1579, Plantin had in plan the establishment of a branch in London, but in connection with the difficulties brought on by the war, this scheme failed to take shape. To one correspondent in London his sales, in 1568, amounted to 4400 florins. The average price of a quarter of a sou per sheet made the cost of an octavo volume of three hundred and twenty pages something less than four francs. The paper and the ink used were of decidedly better quality than those that can be purchased by the most exacting publishers of to-day. Scholarly service could be obtained from editors and authors at very moderate rates, while the labour of the employees was also low priced. The general purchasing power of money three centuries ago was far greater than to-day, and can possibly be estimated between, for instance, Antwerp of 1560 and London of 1890, as worth three times as much, valued by its equivalent in food and clothing. In 1577, Plantin sold his shop in Paris to his agent Sonnius, accepting for the business a sacrifice price. The Netherlands had been devastated by years of war; trade was practically at a standstill, and Plantin was in pressing need of funds.