Читать книгу Trekking in Mallorca. GR221 - The Drystone Route through the Serra de Tramuntana онлайн

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Lime burning

Limekilns are seen throughout the woodlands in the mountains. They are quite different from those seen in Britain, as they lack a draw-hole at the bottom, and are simply deep, stone-lined pits. Great heat was needed to split the calcium carbonate (CaCO³) into calcium oxide (CaO) and carbon dioxide (CO²), so a plentiful supply of wood was necessary. Although a vast amount of limestone is available, the stones used to produce lime were always chosen very carefully, and were referred to as pedra viva or ‘living stones’.

At the base of the pit, a dome was built of large stones with gaps left between them for aeration. Above the dome, more stones were built up, and the spaces around the sides of the kiln were filled with the actual stones that were to be converted into lime. The interior was filled with wood and the top of the kiln was covered with earth. The fire was lit and kept burning for up to two weeks, with more wood added continually. Huge quantities of wood were needed – up to 155,000 kilos (150 tons) – leading to devastation of the forests and producing as little as 10,000 kilos (10 tons) of lime. It was very hard work and it brought little financial reward. According to an old proverb, ‘qui fa calç, va descalç’, or ‘he who makes lime goes barefoot’. Lime was used for the annual whitewashing of houses and also for making mortar.