born Jan. 17, 1761, Dunglass, East Lothian, Scot.
died June 23, 1832, Edinburgh
Scottish geologist and physicist.
He founded experimental geology by artificially producing various rock types in the laboratory. He saw that he could obtain different kinds of rocks by melting minerals and cooling them at a controlled rate. Later he produced a rock that closely resembled natural marble by heating calcium carbonate under pressure. He experimented extensively with igneous rocks from Scotland and showed that they had been produced by intense heat.