Time Reckoning: Why Time Reckoning?
Why does Michael include so much about time in his text?
We take our ability to tell time for granted. But imagine the situation of mariners leaving Venice on a six-month voyage, without clocks, radios, or other devices to keep them in sync with the rest of the world. They were in danger of losing track of time altogether.
There were, however, many reasons why time had to be closely observed.
Time constraints and keeping time
First of all, galley crews toiled under severe time constraints.
Military galleys, for instance, were frequently ordered to rendezvous with other ships on specific dates.
Commercial galleys were governed by very strict orders concerning the days they were to arrive at ports and towns along their route. Severe fines could be levied if they failed to load cargo at their ultimate destination and depart on the set date. Investors wanted the galleys to return to Venice in time for major trade fairs or to ensure that goods bought in the East could be transferred to galleys bound for the West (or vice versa) before those ships left port.
If only for these reasons, someone had to keep track of time on board a galley. Michael's manuscript and other texts of the time suggest that this task fell to senior officers like the paron, comito, or armiraio. These mariners, already accustomed to observing the sky for navigational purposes, were the logical choice.
An ambitious man like Michael would have quickly learned time reckoning to keep his ships on time and earn further promotions.
Personal ambition no doubt informed much of Michael's attention to time reckoning. However, it is notable that although he spends much time on the phases of the moon, he ignores the relationship of the moon to tides, which are mentioned only in the portolans. As with his mathematics—and possibly because it presented so many mathematical puzzles—Michael pursued the subject in his manuscript far beyond what was needed for normal practice or promotion.