Graduated bar scale. A printed plan showing the sheer lines with superimposed inboard detail, body with sternboard and longitudinal half-breadth of the 'Firebrand' (1831), a Firebrand class wooden paddle gunvessel, later an Admiralty yacht.

The plan is credited to 'John Weale; High Holborn, London'. A reference number on the drawing reads 'Plate CXII' and dates it to 1838.