§ 11 Of White Pisan Marble
A kind of white marble, akin to limestone, is found likewise at Monte San Giuliano near Pisa.78 It has been used for covering the outside walls of the Duomo and the Camposanto of Pisa, as well as for many other ornaments to be seen in that city. Formerly the said marbles were brought to Pisa from the hill at San Giuliano with trouble and expense, but now it is different, because Duke Cosimo, in order to make the district more healthy and also to facilitate the carriage of the marbles and other stones taken from those mountains, has turned into a straight canal the river Osoli and many other streams, which used to rise in those plains and do damage to the country. By means of this canal, the marbles, either worked or rough, can be easily conveyed, at a trifling cost, and with the greatest advantage to the city which is now almost restored to its former magnificence, thanks to the said Duke, who has no object more dear to him than that of improving and restoring the city, which was falling into ruins, before His Excellency became its lord.79