An elaborate baroque engraving serves as a headpiece. It depicts a winged female figure, likely a personification of Astronomy or Science, seated upon a stone plinth. She is crowned with a celestial halo representing the sun and planetary orbits. In her left hand, she holds a document featuring astronomical diagrams, including circles and a quadrant. To her left stands a small plumb line. To her right is an ornate, scroll-worked cartouche (shield) bearing an interlaced monogram of two 'C's. In the background to the right, a large scientific instrument, possibly a mural quadrant or transit instrument, is positioned with a small cherub or putto interacting with its mechanism.

ILLUSTRIOUS SIR

Since you have commanded, Illustrious Sir original: "Vir Illustris" — a formal honorific for a nobleman or high-ranking official, that those things which I have partly collected and arranged in order, and partly contemplated myself during these past years concerning the motion of bodies original: "motu corporum" — referring to the physics of moving objects or celestial mechanics, should be printed in type, I do not hesitate to offer and dedicate them especially to You. For so great are