Thomas Clark (1793-1864) was a brother of the John Clark. By 1810 he had moved to Bridgwater, and set himself up as a grocer. He married Elizabeth Bull in 1833, and by her had one son, who died soon after his birth,. She died in 1837. Their grave marker may be seen in the Quaker burial ground at Bridgwater.
Clark became one of the Anstice, Baker and Bowen circle soon after arriving in Bridgwater, and a later friend of his was the Revd J. C. Collins of Saint Johns, with whom he used to go botanising.
Clark's was a meticulous botanist, and wrote a paper on the rare plants of the turf moors, published in 1856 by the Proceedings of the Somerset Archaeological and Natural History Society.
His nature diary 1853-1864 is in Blake Museum. As well as notes about the plants he kept a meticulous record of the weather. He died at his residence, Halesleigh, Wembdon; now the Quantock Gateway Hotel.
Edward H Milligan, Biographical Dictionary of British Quakers in Commerce and Industry, 1775-1920, 2007, p 110