Mounted with PAF2929-PAF2955, PAF2957-PAF2956; page number 28. The central image shows a detail of Bradley's transit room (c. 1750), looking south, at the Royal Observatory with John Bird's 8-foot transit instrument (AST0980) in place defining Bradley's Greenwich meridian of 1750, which remains the basis of British Ordnance Survey maps (the Survey having begun in the 1790s). Tucked behind the right-hand pillar is the regulator clock known as Graham No. 3 (ZBA0709), delivered in 1750, which was the principal transit clock throughout Nevil Maskelyne's tenure as fifth Astronomer Royal from 1765 to1811. The other instruments are unidentified telescopes etc., which may have been at Greenwich since Charnock lived locally and had access to do these drawings through his naval connections, probably in the 1790s.