GRIFFITHS, Robert. Description of Griffiths' Patent Screw Propellor; with its recent improvements, London: Robert Griffiths, 1858, 4°, 12pp., folding wood-engraved frontispiece [bound with:] The Screw Propellor: and what it is and what it ought to be, London: E. and F. N. Spon, 1860, 4°, 12pp., 2 pamphlets in one volume, late 19th-century half calf (lightly rubbed), Scott bookplate. [Scott 720] -- Julian John REVY. The Progressive Screw as Propellor in Navigation, London: John Weale, 1860, 8°, FIRST EDITION, one folding engraved plate (torn along fold), later half calf, Scott bookplate. [Scott 729] (2)