Wilhelm Homberg

Wilhelm Homberg (1652 to 1715), known in French as Guillaume Homberg, was a German natural philosopher who worked at the point where alchemy was turning into chemistry. He was born at Batavia, now Jakarta, where his father served the Dutch East India Company, studied law at Jena and Leipzig, and turned to natural science after meeting Otto von Guericke in Magdeburg. After graduating in medicine at Wittenberg he settled in Paris in 1682, practised in Rome from 1685 to 1690, and was elected to the Academy of Sciences in 1691, later teaching physics and chemistry and serving as private physician to the duke of Orleans. Before 1700 he worked mainly on pneumatics and the vacuum with an improved air pump of his own design, and he recorded observations on Kunkel's phosphorus, the green colour copper gives to flames and the saturation of bases by acids. In 1702 he discovered boracic acid, known as Sal Sedativum Hombergi.