Thomas Trevithick was born in Gwennap, Cornwall, the son of Thomas Trevithick (1791-1844) a copper miner, and Mary nee Spargo (1780- c.1850) At the age of 17 he was converted and became a Wesleyan Local Preacher and Class-leader. Following his father he trained as a mining engineman and later as a mining engineer. In 1848 he married Sarah Holman at Gwennap. In the same year he went to Mexico and then in 1850 to Tuolumne, California where he worked in the mining industry. Whist in Mexico and California he took every opportunity to preach the Gospel to his fellow workers and their families.
In 1856 he returned to the United Kingdom and was appointed as captain at Parys mountain mine on Anglesey. He was also a mine agent. He was active in the Wesleyan churches at Amlwch, Anglesey and in ???. Thomas and his wife lived at Amlwch. The Watchmen and Wesleyan Advertiser during July and August 1858 and 1859 advertised English Service in Llandudno and visitors were invited to contact Captain Vivian, Captain Trevithick, or Mr. S. Bartley. Thomas was also a teetotaller, addressing young people at the Band of Hope.
In 1872 Thomas and his wife left North Wales to take up work at Frampton Cotterell in the Thornbury Circuit, where he continued to preach until his death on 14th July 1876.
North Wales Weekly 27 April 1861