Engraving of Sir Francis Pettit Smith. Thomas Oldham Barlow. Print, mezzotint, on laid india 46x38cm., platemark 33.2x25.7cm., oval image 22.6x18.6cm., portrait, HS to L. Title as facsimile signature, pencilled inscription 'T. Oldham Barlow', unpublished proof Prof. B. Woodcroft. Francis Pettit Smith (1808-1874) was an English co-inventor of the screw propeller and the driving force in the construction of the first screw-propelled steamship. Thomas Oldham Barlow (1824-1889) was an English mezzotint engraver who popularised the work of many painters