J H Clark was born in Gloucester in 1818 and set up in business as a printer in Usk in 1834. In 1868 he produced 'Sketches of Monmouthshire', one of the many guides he wrote and printed, with an appendix which he later reprinted as a pamphlet entitled, 'The Flora of Monmouthshire'. This was the first attempt to produce a complete flora of the county.