Summary
In the collection of Watt's papers at Doldowlod, home of Lord Gibson-Watt, there are seven previously unpublished letters from James Hutton to James Watt, and four letters from Watt to Hutton, also unpublished. The letters were written between 1774 and 1795. Very little of Hutton's other correspondence survives, so these letters add significantly to our knowledge. The earliest letters, together with two letters to George Clerk-Maxwell (in the Scottish Record Office), describe geological tours that Hutton made through Wales, the Midlands, and the south-west of England in 1774. The correspondence after 1774, which will appear in a later edition of Annals of Science, reveals Watt's expertise in geology, and also discusses meteorology, varnish making, Symington's steam engines, the first experiments with steam navigation, pneumatic medicine, and other topics.