228 On the Force, Construction, fyc. 



authorities should be so much exposed to its deceptions, for 

 want of a scientific reference of this description and its legiti- 

 mate deductions. 



A ship of the line to be fully effective in action, when the 

 weather is rough, should not, in any case, have the lower port- 

 sills a less height above the water's level surface than 5 feet 9 

 inches, or 6 feet ; and in one of two decks this height may be in- 

 creased to 6£ or 7 feet without materially compromising other 

 good qualities. There is, no doubt, some difficulty in effecting 

 a greater height than 6 feet in ships of three decks, and they 

 have already so much hull above water, that it becomes an 

 object to prevent a further increase ; but the same objection 

 exists only in a far inferior degree in a ship of two decks ; and 

 as the failure of its lower battery would put it out of the line 

 of battle, and, with the usual armament, would render it 

 inferior in force to the heavy frigates of the present day, it be- 

 comes a matter of still graver importance to secure this class 

 of ships of the line from losing the fire of their lower tier of 

 ordnance. 



The weight of the volume of water displaced by a ship 

 when fully equipped for service, is susceptible of being divided 

 into two principal parts, viz., the weight of the hull, and the 

 weight of the equipment, in which we include the masting and 

 ballast. The first-mentioned of these weights may be con- 

 siderably varied from a difference in the practical carpentry, 

 and in the specific gravity of the timber material used ; but 

 the second being that incidental to the armament, or such as 

 is positively incurred by the adoption of a certain force, must 

 bear a constant ratio, or nearly so, to that force, in ships of 

 the same nation. What variation there may exist, must con- 

 sist principally in the alteration of the stores and crew, from 

 the war to the peace establishment, or from home to foreign 

 service proportions. As, however, the good qualities of a 

 ship-of-war are most especially valuable and desirable in belli- 

 gerent times and on foreign stations, we should prefer construct- 

 ing the best ship to meet such circumstances, and at the same 

 time endeavour to preserve the permanence of its good qualities 

 as much as the gradual consumption of water, provisions, and 

 stores will allow. 



The two following Tables will indicate very nearly the general 



