Prosperous Pit Engine, Long Benton, Northumberland Design for the machinery for forming the scfew upon the barrel of Long Benton water gin Elevtiona and sections, scale 1:24 Ink wash Signed 1777 Inscribed: For explanation see Book 6, Reports and Estimates, page 215 [Refers to mechanism for cutting the screw-head on the wooden conical barrel] 1777