In 1419 two captains of Prince Henry the Navigator, João Gonçalves Zarco and Tristão Vaz Teixeira, were driven by a storm to the island they called Porto Santo, or Holy Harbour, in gratitude for their rescue from shipwreck. The next year an expedition was sent to populate the island, and, Madeira being described, they made for it, and took possession on behalf of the Portuguese crown, together with captain Bartolomeu Perestrello. The islands started to be settled circa 1420 or 1425. On September 23, 1433, the name Ilha da Madeira (Madeira Island or "island of the wood") appears in a map, by the first time, in a document. The three captain-majors had led, in the first trip, the respective families, a small group of people of the minor nobility, people of modest conditions and some old prisoners of the kingdom. To gain the minimum conditions for the development of agriculture, they had to rough-hew a part of the dense forest of laurisilva. Then fires were started, which are said to have burned for seven years. The colonists constructed a large number of canals (levadas), since in some parts of the island, they had water in excess while in other parts water was scarce.The manual work was done by enslaved Africans brought from the African mainland. They were soon put to growing and refining sugar, which was much in demand in Europe and highly profitable. As the slaves were worked to death and the women were unable to bear children, more and more Africans were captured and brought to the island. This pattern for sugar cultivation became the model that would soon be transferred to the Caribbean and Brazil. In Madeira it became evident that a warm climate, winds to work windmills for sugar crushing and easy access to the sea (for transportation of the raw sugar to Europe) were, together with slave labour, important components in what became a huge and highly profitable industry, which funded industrialisation and European expansion.