342 On the Force^ Construction, <^c. 



By ascertaining the weights of the hulls, we are in possession 

 of the average weight of hull per foot of the length ; which, in 

 the English 120, 84, and 74-guns, is respectively 12.3, 9.77, 

 and 9.6 tons. Hence, from knowing these facts, and having 

 the data furnished in Table II., we may venture with a coa- 

 siderable degree of certainty on the design of new classes of 

 ships, similar in form and practical construction, but carrying 

 armaments different, both in force and adjustment, to those at 

 present used. Suppose it to be required to assign the displace- 

 ment for a ship of 98 guns on two decks instead of three ; viz. 



_ , , , , ( Thirty-two 3 2-pounder lonar guns. 



On the lower deck . . -^ rp L a ^ 



( Two es-pounder carronades. 



„ upper deck . . Thirty-six 24-pounder long guns. 



„ quarter-deck and i Eighteen 32-pounder carronades. 



forecastle . \ Ten 24-pounder Congreve guns. 



As the armament here proposed is similar to that of the Eng- 

 lish 84-gun ship, (Table II.) we shall have the real tonnage 

 per gun, (exclusive of ballast,) 19.65 tons ; ballast, per gun, 

 3 tons nearly ; and the weight of hull, per foot of the length, 

 9.77 tons *. Now the length required to put 17 guns into 

 battery on each side, besides the bow-port, will be 217 feet ; 

 hence, . 



217x9.77 = 2120.09 tons for weight of hull. 



98 X 3 = 294.00 tons for weight of ballast. 

 98 X 19.65= 1925.70 tons for real tonnage, exclusive of ballast., ;C' 



Sum 4339.79 tons for whole displacement. 



But if the new 32-pounders, of 8 feet long, and of the same 

 weight as the 24-pounders, be substituted for the latter on the 

 upper deck, the increase of weight incurred thereby will be at 

 the rate of .56 tons per gunf , so substituted, which, in 36 guns^ 

 will amount to 20.16 tons, and will increase the displacement 

 to 4339.794-20.16=4359.95 tons. And if the 32-pounders, 

 of 56cwt., were niounted on the upper deck, there would xe- 



* We presume the scantlings of the timbers, &c. to be the same in the two cases; 

 and there can be no doubt but that 9 .77 tons per foot of the length is quite suffi. 

 cient to ensure a proper degree of strength to the proposed ship. Chapman allows 

 only 8.96 tons in his 110 gun ship, 

 f Vide Table VI. 



