Robinson Manby Johnson (1849-1894) was born in Kensington, London, the son of Henry Johnson, a Dronfield file manufacturer, and his wife Isabella.  The family had interests in local coal mines: Henry’s brother-in-law was George Lucas, a coal master, while Isabella in the Census (1851) described herself as a ‘proprietor of land and coal mines’.  By 1871, Robert M. Johnson had joined Frederic Lucas (probably George’s son) to form Lucas & Johnson, Britannia metal and electro-plate manufacturers at Shoreham Works, Shoreham Street.  In 1874, the partnership was dissolved and in the following year R. M. Johnson & Co registered a silver mark from the same address.  It proved to be a short-lived venture.  In 1879, the firm was dissolved, though Bernard Lucas Johnson agreed to take over.  However, within months Lucas retired through ill-health and left for Australia and the stock was auctioned at Cutlers’ Hall.  (Shoreham Works was later occupied by Roberts & Co and Harrison, Bros & Howson)  The dissolution of the company coincided with the collapse of the Dronfield Silkstone Coal Co Ltd, in which the Johnson family had interests and were the major creditors.   In 1881, the Census listed Robinson M. Johnson as retired, aged 31; however, by 1891 he was a commercial traveller.  He died on 9 April 1894, aged 45, and was buried in the General Cemetery.  He left his widow, Charlotte, less than £15.  The trade mark was ‘RMJ & Co’ and ‘ELECTRO’.