The history of the caravel known since 1471 as 'Peter von Danzig' gives us an insight into the use of wind power and sails. The caravel, built in la Rochelle on the Atlantic as 'S. Pierre la Rochelle', sailed to its maiden voyage in 1462 under the command of Aymar Beoff, carrying a cargo of salt to Gdansk. In Gdansk it was damaged by a storm and stayed for ten years in the port on the Motlawa. Pledged by the second-in-command Pierre Nates to Gdansk burghers Rudolph Feldstete and Caspar Lange in May 1464, it had been falling into disrepair until the spring of 1471, when the city council decided to renovate it and to use it in the war of the Hanseatic League against England. The caravel was a three-master, equipped, as is indicated in the 1464 letter of pledge, with three basic sails: a foresail on the foremast, a square mainsail on the mainmast and a lateen sail on the mizzenmast. On the 19th of August 1471 the renovated ship, renamed 'Peter von Danzig', sailed to war with the British, armed with 18 cannons and carrying a crew of 350 men commanded by the city councillor Berndt Pawest. Pawest's detailed reports, describing the daily service of the caravel, are an excellent source of data on the history of the ship and the mediaeval technique of sailing, especially the use of wind power and sails. Pawest describes several occasions when the caravel was beset by winds on the Northern Sea. His account of an action at the English coast at the beginning of 1472 brings particularly valuable information on the role of wind in mediaeval sailing. The ship suffered a leak and water had to be pumped out; as a result the crew had to fight hard with the wind to navigate to Zwin (Swin), where the caravel had to be repaired for several months before it was fit to set sail again in the autumn of 1473.