The Determination of the Ship’s Speed in History and the Earliest Discussion of the ‘Dutchman’s Log’
Early mariners did not have the means to ascertain their exact position once they were out of sight of land for some time. But, contrary to an assumption long nurtured, early mariners did not usually ‘hug the coast’. In Roman times the Mediterranean mariners had to cross the basins of that sea to carry goods, especially grain and olive oil, to Rome or Athens. That was not difficult, though, as shipping was in tune with, and dependent on, the seasonally prevailing winds. The grain-carrying Roman ships, for instance, did not sail in winter but waited on the North African coasts until the ghibli blew in spring and summer to then cross the Tyrrhenian Sea. For that they needed neither compass nor log, which were only introduced many centuries later, for one could be sure to arrive at the opposite shore within a few hours or days anyway. In consequence the early sources do not deal with the speed of ships….
Filed under: Mediterranean
Subjects include: Science & Exploration | Ship Handling & Seamanship