HALL, SIR JAMES, 4TH BARONET

born Jan. 17, 1761, Dunglass, East Lothian, Scot. died June 23, 1832, Edinburgh Scottish geologist and physicist who founded experimental geology by artificially producing various rock types in the laboratory. Hall succeeded to his father's baronetcy in 1776 and thereafter studied at Christ's College, Cambridge, and the University of Edinburgh. He later became president of the Royal Society of Edinburgh. For many years he rejected the belief of his friend, the noted Scottish geologist James Hutton, that many rocks have an igneous origin, but eventually he came to believe that Hutton's views might be subject to experimental testing. By melting minerals and cooling them at a controlled rate, Hall found that he could obtain different kinds of rocks. Later, he found that by heating calcium carbonate under pressure he could produce a rock closely resembling natural marble. He experimented extensively with igneous rocks from Scotland and showed that they were produced by intense heat.