Thomas Clark (Unknown – October 6, 1835) was a businessman and political figure in Upper Canada. He was born in Scotland and came to Upper Canada in 1791 to seek employment with his cousin, Robert Hamilton. In 1796, he opened a store in Queenston. He then formed a partnership with Samuel Street to transport goods around Niagara Falls. He owned docks and storage facilities at Queenston, Chippawa and Fort Erie. In 1800, when Street left the partnership, he formed a new partnership with Robert Nichol transporting and trading in goods which lasted until 1803. In the same year, he was appointed justice of the peace. Around 1808, he set up several large flour milling complexes with Samuel Street. Besides his partnership with Street, Clark also had an agreement with John Jacob Astor and others fo