ALLEN, WILLIAM, an eminent pharmaceutical chemist, and chemical lecturer in London, was born in 1770. He early showed a predilection for experimental investigations, and was placed in a respectable pharmaco-chemical establishment in Plough Court, in which he afterwards became a partner with Luke Howard. While successfully pursuing his business Allen engaged in various important experimental investigations. In 1804, he was appointed lecturer on chemistry at Guy's Hospital, an office from which he did not finally retire till 1827. He became a fellow of the Royal Society in 1807; and several of his communications appear in the Philosophical Transactions, especially the important experimental researches by him and Mr Pepys on Respiration. He was a zealous member and a president of the pharmaceutical society. But along with his scientific occupations, he was an active promoter of various schemes of benevolence. He had purchased an estate near Lindfield in Sussex, to which he retired several years before his death. There he devoted himself to the establishment of schools, to which workshops for the children, a library, and experimental laboratory were attached, and where he himself gave occasional instruction to the young experimentalists. He was highly esteemed in private life, and died, much regretted, at his house near Lindfield, in 1843. (T. S. T.)