492 SEC. 12. APPLIED MECHANICS. 



2148g. Table of the first 5O Voyages of the " Great 

 Western " steamship. 



Maiidslay, Sons, and Field, Engineers. 



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



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



2176. Varying-pitch Screw Propeller on shaft 



Bcnnet Woodcroft, F.R.S. 



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

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



Bcnnet Woodcroft, F.R.S. 



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. 



2180e. Memoir, written by Don Fernandez Duro, upon the 

 models of metal plated ships made in the last century, preserved at 

 the Ministry of Marine at Madrid. With plates. 



Archceological Museum, Madrid. 

 2 149 a. Drawing of Steam Vessel, by the exhibitor. 



The late Baron Seguier, Membre dc VInstitut. 



EXHIBITED BY THE SOUTH KENSINGTON MUSEUM. 



2178fk. Model of the After Body, showing complete 

 framing, of the Screw Steamer "Novelty." Built 1839-40. 

 Mr. H. Wimshurst. South Kensington Museum. 



This vessel was the first fitted with direct-acting engines to drive the screw, 

 and having means also of shipping and unshipping the propeller. 



2155. Model, on a T ^ scale, of the Horizontal Con- 

 densing Screw Engines of H.M. Ships *' Nelson," built 

 1814, altered for the screw propeller 1860; "Conqueror," built 

 1833, altered for the screw propeller 1859 ; and ** Tainar," built 

 1863. The engines are of 500 horse-power, nominal. Diameter 

 of cylinders, 71 inches; stroke, 3 feet. Ravenhill, Easton, and 

 Co., Engineers, Ratcliff, London. South Kensington Museum. 



2160. Model of the Engines of the Paddle-wheel 

 Steamer " Helen McGregor," of Liverpool. 

 Designed in 1843 by G-. Forrester & Co., Engineers. 



South Kensington Museum. 



This engine has two inverted steam cylinders of very long stroke, driving 

 one crank on the paddle shaft. It is a condensing low-pressure engine, it 

 occupies but little hull space, and is said to be still at work, 1873. 



