A George IV brass pantograph, Cary, London, circa 1825 The pivoted frame with circular dark green silk covered anchor-weight fitted to an adjustable slider against engraved ratio scale to one arm opposing fixed pencil holder to the other, the centre with subsidiary pivoted armature with further adjustable slider against a similar scale for the tracing stylus and signed Cary, London to the opposing member, fitted with removable bone wheel castors to each junction/terminal, in original mahogany box with tracing pointer and weighted pencil carrier, the box 73.5cm (29ins) long. William Cary is recorded in Clifton, Gloria Directory of British Scientific Instrument Makers 1550-1851 as born circa 1759 and apprenticed to Jesse Ramsden. William worked from 272 Strand, London 1789-90 then 182 Strand 1794-1822, he died in 1825. John Cary (I) is recorded by Clifton as a map, globe and chart engraver who was born in 1755 and worked from Johnson's Court, Fleet Street 1782 then Corner of Arundel Street, Strand 1783 before moving to 188 Strand 1783-1790 followed by 181 Strand 1792-1805. He is last recorded working at 86 St. James Street 1820-21. The business was continued by John (II) and George Cary (both sons of John senior) until circa 1851 when it was acquired by Henry Gould.