In 1784, he was apprenticed to Messrs Taylor & Co, an engraving and die casting works in Birmingham owned by a Mr Benjamin Patrick. The engraved buckles and buttons in which Patrick's factory specialised became unfashionable, however, and the business went into decline. In 1788, Lambert returned to Leicester, to serve as his father's assistant at the gaol (some sources date Lambert's return to Leicester to 1791, following the destruction of the building housing Messrs Taylor & Co in the Priestley Riots of ). His father retired soon afterwards and Lambert succeeded him as gaol keeper. The younger Daniel Lambert was a much-respected gaoler; he befriended many of the prisoners, and made every effort to help them when they went to trial.