328 A Digest oj the Plans of Ships in the British Navy, [Nov. 



The foregoing sketch of an analysis of the ships of the navy, 

 with a view to derive from it a body of experience to guide the 

 designs of his Majesty's ships, includes all the principal elements 

 of a ship's composition. There is no new calculation introduced, 

 except l)r. Tnman's for ascertaining the necessary form between 

 wind and water to produce transverse motion in rolling, and the 

 experiment for finding the centre of gravity of the ship and con- 

 tents. A regard has been had to making the comparisons on a 

 general and comprehensive scale, rather than on a minute refer- 

 ence to particulars, which do not materially affect the ship's 

 qualities, and would render the calculations extremely diffuse. 

 At a more advanced period of the science of naval architecture 

 in this country, an analysis more refined in its parts may be used 

 for comparing cases of particular interest, when the principal 

 limits have become famiharly known. 



The manner in which the inductive mode of philosophy is here 

 applied to ascertain the principles of ship-building, from its 

 extreme brevity, is more imperfect than it is thought the project 

 itself is capable of being shown to be. In a future article some 

 account of experiments on ships, to ascertain the relative velocity 

 of the ship and wind, and the centre of mean resistance, will be 

 given. 



Our navy of England consists of 500 ships of war, of which 

 120 are line-of-battle ships. Of these, about two-thirds may be 

 said to be ** good conditioned ships for sea." The extent of the 

 calculations, therefore, appears very great. It must be remem- 

 bered, however, that there are only six difierent rates, which 

 have, for the most part, the same masts, rigging, guns, provi- 

 sions, 8cc. ; and that in some cases 30 or 40 ships are built from 

 the same draught. The variations are, therefore, not so great as 

 might be imagined. Interpolations may also be used that will 

 give results with a sufficient nicety. 



The liberality which the Admiralty have extended to the 

 institution to which I have the honour to belong, renders obliga- 

 tory every exertion on our part to promote the object of their 

 Lordships in the improvement of the navy; and I shall be 

 extremely happy if the foregoing disquisition should efiect it in 

 a humble degree. 



