VII, NAVAL ARCHITECTURE, ETC. 427 



2172. Four-bladed or Two-bladed Screw Propeller. 



Royal Naval Museum, Greenwich. 



2173. Working Model of a pair of Inverted Cylinders 

 Marine Engine for driving a screw propeller. Cylinders 

 2| inches bore, stroke 4 inches, link motion and reversing gear 

 complete, shut-off valve, &c. Full sized partly shaded drawings of 

 same. Made by exhibitor during his apprenticeship. 



Robert Lathbury. 



2174. Model in mahogany of a Three-bladed Griffiths' 

 Patent Screw Propeller. Made by exhibitor during his 

 apprenticeship. Robert Lathbury. 



2175. Models (3) of Varying-pitch Screw Propellers, 



Woodcroft's Patent, 1838. Bennet Woodcraft, F.R.S. 



2176. Varying-pitch Screw Propeller on shaft. 



Bennet Woodcroft, F.R.S. 



2177. Skeleton Model of part of a Vessel fitted with a 

 Screw Propeller. (Cummeron's Patent, 1828.) 



Bennet Woodcraft, F.R.8. 



2178. Model of Vessel fitted with Screw Propeller, by 



Sir Francis Pettit Smith. Bennet Woodcraft, F.R.S. 



The propeller consists of two whole turns of a screw thread round its shaft, 

 and is placed in the dead wood or run of the vessel, but by a memorandum 

 of alteration the patentee limits himself to a screw of one turn or two half 

 turns. 



2178a. A Photograph of the "Germanic" and 

 ** Britannic " mail steamers, belonging to the " White Star " 

 line from Liverpool to New York. An abstract log of one of the 

 voyages of the " Germanic " is attached to the frame. 760 horse- 

 power nominal, four cylinder compound engines by Maudslay, 

 Sons, and Field. Ships built by Harland and Wolff, of Belfast. * 

 Maudslay, Sons, and Field, Engineers, Lambeth. 



2178b. Model of a Yarmouth Herring Fishing Lugger 



getting her nets in. Exact model and position of men when at 

 their work. John Bracey. 



2178c. Model of a Yarmouth Trawling Smack. With- 

 out the trawl net. John Bracey. 



2178d. Model of a Bow of a first rate ship-of-war, showing 

 the disposition of the frames and hawse pieces. Wm. Moody. 



2178e. Model of a Stern of a first rate ship-of-war, 

 showing the disposition of the stern timbers and frames. 



Wm. Moody. 



