It advertises his 'Rotisseurs Royal', i.e. his 'new invented Machine for Roasting Meat' etc., and his 'New Invented Harpsichord', and money scales, balances and 'Mechanical Chairs for the use of Infirm Persons'. Verso bears ms. note re Merlin's 'Roasters'. Merlin took out patents for a 'spring jack' with a reflector to increase the heat (1032 of Jan 1773), and for a harpsichord (1081 of Sept 1774).