- 1Collection of letters and accounts relating to Richard Trevithick's patent on a portable high pressure steam engine (MS/1944)
1803-1808, fonds - 2A statement of the premiums owned on Trevithick's patent for high pressure steam engines (MS/1944/01)
1804, item - 3Statement of accounts between Messrs Trevithick and Co and Samuel Homfray (MS/1944/04)
December 1803-July 1807, item