John Thomas Duncan was born in Glasgow in 1855. After his family moved to Plymouth he commenced training as a shipbroker. After a short period of employment at Cherbourg, he entered the offices of Edward Earl and Company in Cardiff. In 1883 he began trading on his own account. In 1889 he entered into a partnership with Jacques Victor Valette under the name of Duncan Valette and Company. The first vessel they purchased was the Benefactor. In addition to his interest in Duncan Valette and Company, J.T. Duncan acquired a number of shares in single ship companies managed by others. This resulted in Duncan Valette and Company being appointed to represent all these vessels at Cardiff and other Bristol Channel ports. In 1895 J.V. Valette withdrew from the partnership and the company was reconstituted J.T. Duncan and Company. In 1898 J.T. Duncan acquired shares in the Shamrock Shipping Company. This led to an agreement whereby J.T. Duncan and Company became the Bristol Channel agents for the Shamrock fleet which was employed in the coal trade between south Wales and the French channel and Bay of Biscay ports. By the 1960s the south Wales coal trade was in serious decline and the company were no longer ship onwers but they continued in business as shipbrokers and forwarding agents. In September 1978 the firm passed into the hands of its former Swansea agents Stockwood, Rees and Company.
Source: Glamorgan Archives