[Letters (6)] 1802-1828 [to] Richard Trevithick/Andrew Vivian. [/1: 1802 Feb 23, Camborne, gives news of Trevithick's family, local gossip and business affairs, (published in Life of Richard Trevithick/Francis Trevithick, 1872, v.1, p.114-5); /2: 1802 Mar 23, Southampton St., describes his attempts to secure their joint patent for the high pressure steam engine (no.2599 of 1804 Mar. 24), (published in Life of Richard Trevithick/Francis Trevithick, 1872, v.1, p.115-7.); /3: 1805 May 22, Camborne, describes death of his son, also Andrew, and his own attempts to sell his share in the joint patent of 1802 (Mar. 24, no.2599), (published in Life of Richard Trevithick/Francis Trevithick, 1872, v.1, p.229-30); /4: 1805 Jul 1, Camborne, concerns patent and business controversies, (published, almost complete, in Life of Richard Trevithick/ Francis Trevithick, 1872, v.1, p.230-1, unpublished lines concern shipping of "the Gig" from London to Cornwall); /5: 1806 May 30, Camborne, concerns, at length, performance of Cornish mine engines, outputs from individual mines and current projects, (published, with some minor paraphrasing and misreadings, in Life of Richard Trevithick/Francis Trevithick, 1872, v.2, p.150-2); /6: 1828 Jan 10, Camborne, Vivian has looked through his papers and cannot find "any thing relative to the business that will be of any use to you"; suggests Trevithick should contact Davies Gilbert.]