Sidereal Messenger and Kepler's Dioptrics

TO THE MOST SERENE

COSMO DE' MEDICI, THE SECOND,

Cosimo II de' Medici (1590–1621) was the Grand Duke of Tuscany and a former pupil of Galileo Galilei. This dedication was a crucial step in securing royal patronage.

FOURTH GRAND-DUKE OF TUSCANY.

THERE is certainly something very noble and large-minded in the intention of those who have endeavoured to protect from envy the noble achievements of distinguished men, and to rescue their names, worthy of immortality, from oblivion and decay. This desire has given us the lineaments The features or characteristic outlines of a face. of famous men, sculptured in marble, or fashioned in bronze, as a memorial of them to future ages; to the same feeling we owe the erection of statues, both ordinary and equestrian; hence, as the poet¹ says, has originated expenditure, mounting to the stars, upon columns and pyramids; with this desire, lastly, cities have been built, and distinguished by the names of those men, whom the gratitude of posterity thought worthy of being handed down to all ages. For the state of the human mind is such, that

¹ original: "Propertius, iii. 2. 17-22." This refers to the Roman poet Sextus Propertius. The cited lines claim that while the Pyramids and grand tombs will crumble, the genius of a poet's wit is a "memorial that shall not die."