Room II displays two groups of instruments of great importance. The first includes the precious instruments that Prince Mathias, brother of Ferdinand II de' Medici, acquired in Germany: quadrants, astrolabes, and surveying instruments, signed by the most celebrated makers in Europe, such as the Schisslers. The second group includes the innovative nautical instruments designed by Sir Robert Dudley, Duke of Northumberland, and bequeathed by him to the Medici: nautical astrolabes, theodolites, and quadrants made in England during the reign of Elizabeth I. Also exhibited are other instruments of foreign manufacture: Chinese compasses, one of the first mechanical calculators (developed by Samuel Morland and dedicated to Grand Duke Cosimo III), and splendid Flemish astrolabes. This selection demonstrates the international scope of the Medici collections. The ambition of assembling a collection of marvels gave way, in the seventeenth century, to the quest for innovative instruments, chiefly appreciated for their usefulness.