January 20, 2013. 8:30 a.m. Paris time. Salon-de-Provence France. Beneath
L‟Ecole St. Michel.
Professor John Morse studied the notes he had made. Somehow these clues must
together form a word to open the vault door. The answer, he thought, must lie in the
astrolabe. Morse studied the astrolabe on the podium. The astrolabe was round, about a
foot in diameter, and made entirely of brass. There were markings around the edge of the
astrolabe in concentric circles. There was a small brass ring at the top about as big as a
thumb. Morse held up the instrument to Father du Bois and his children, holding it by
the ring. ―This is an astrolabe. It is used for determining the altitude of the stars.‖
Morse thought of how best to explain the intricate markings and moving parts on the
medieval astrolabe, and decided it would be best to use a simple analogy they could
understand. He took out his notepad and drew a drinking straw, with a piece of arcing
cardboard attached. He made notches on the drawing for the different degrees, and then
drew in a string attached to one end of the straw, anchored at the end by a washer. His
drawing looked like this: