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One source states that in 1786 he was a Worcester ironworker who moved to Merthyr Tydfil. This seems unlikely as he would only have been 13, and another source states that Richard and his brother William Brown (1770-1853) moved with the family from Broseley (Shropshire) to Pendarren. Richard and William Brown helped to make Richard Trevithick's 1804 locomotive. 
1804 Birth of son Thomas Brown
1809 Birth of son James Brown
1811 Moved with his family and set up the wrought iron bar mills at Nantyglo, Monmouthshire
1851 Living at Brynglas, Malpas, Monmouthshire: James Brown (age 42 born Glamorgan), Tin Plate Manufacturer. With his wife Jane Brown (age 38 born Monmouthshire) With their four children; James Brown (age 12 born Monmouthshire); Richard Brown (age 10 born Monmouthshire); Thomas Brown (age 5 born Monmouthshire); and Jane Brown (age 10 Months born Monmouthshire). Also visitors (appear to be his parents) Richard Brown (age 78 born Salop), Retired Iron Master. With Elizabeth Brown (age 87 born Worcestershire?). One other visitor. Four servants.