Number of words – 328

To make any longer voyages, the Portuguese needed better ships. And in Lisbon, they created a revolutionary new types of ship. The Portuguese built ships that combined two earlier traditions of the North Sea and the Mediterranean. Traditions which differed because of the conditions of the seas they sailed. The northern ships were short, broad and deep. They had to stand up to the rough weather and high seas of the Atlantic. Mediterranean ships on the other hand were designed for smooth weather, they rarely left the sight of land and had a single square sail.

The Portuguese put a large square sail, on the main centre, mast. Ahead of that, they put a second, somewhat shorter, mast, also with a square sail. And behind the main mast they put a third mast carrying a lateen sail. These cross – breed Portuguese ships, carracks and caravels, were the ancestors of the great sailing ships that dominated the oceans of the world for the next four centuries. They were larger than their northern predecessors, and better sailors. And they could withstand Atlantic gales better than the Mediterranean ships. Their design was established between 1440 and 1460, and spread rapidly to other seafaring nations.

If your square rigger on its southward course has the wind coming from the northeast, at 1 4 degree angle to the direction you’re going. You have to set the angle of your sail so it’s diagonal across the ship. To do that you pull in on the sheet at the bottom corner of the sail on the side away from the wind – the western side. Then, if the wind shifts so it’s coming straight from the east you pull harder on the sheet. You’ll keep going, but not so fast. But if the wind shifts to blow from the southeast, you’re in trouble. Lower your sail – or change your direction of travel.

Excerpted from ‘Children of Promotheus: A history of Science and Technology’ by James McLachlan