462 
ME. E. J. EEED ON THE UNEQUAL DISTEIBUTION OE 
moments experienced by this vessel are 12,000 foot-tons for still water, and 43,600 foot- 
tons for a wave-crest, while the maximum sagging-moment in a wave-hollow is 48,800 
foot-tons. The shearing-forces have also been found to have the following approximate 
maximum values: — In still water 210 tons, on a wave-crest 555 tons, and in a wave- 
hollow 640 tons, while aground it equals 3666 tons. The comparative conditions of 
strain of the ship under these different circumstances can be fairly determined by com- 
paring these figures. It is also interesting to remark the different manner in which 
changes of the attendant circumstances affect the strains of the two classes of ironclads 
represented by the ‘ Minotaur ’ and the ‘ Bellerophon.’ The reader can trace these for 
himself ; I would simply call attention to the fact that when aground and supported at 
the extremities the maximum bending-moments bear very nearly the same proportions to 
the products of the lengths and displacements, notwithstanding the very different distri- 
bution of the weight in the two ships. This similarity is mainly due to the fact that the 
centres of gravity of the fore and after bodies in the two ships are very nearly the same 
part of the length of these bodies distant from the bow and stern. For example, in the 
1 Minotaur ’ the centre of gravity of the fore body is 116 feet distant from the bow, and 
the fore body is 201 feet long, these quantities being very nearly in the ratio of 3 to 5 ; 
while in the £ Bellerophon ’ the centre of gravity is 90 feet from the bow, and the length 
of the fore body is 144 feet, the ratio between these quantities being nearly the same as 
before. 
Our third example is drawn from the ‘ Victoria and Albert,’ in which ship the centre 
of gravity is about 157 feet from the bow and 143 feet from the stern. When supported 
at the extremities only, the bow sustains a pressure of about 1120 tons, and the stern 
of 1230 tons; and the centres of gravity of the two parts into which the ship is divided 
by the transverse section containing her centre of gravity are respectively 60 feet before, 
and 46 feet abaft this section. Hence we obtain by the same method as before : — 
Maximum bending-moment =1120 tons X 157 ft. — 1020 tons x 60 ft. 
= 114,700 foot-tons (in round numbers) ; or about 
= displacement in tons X ij of the length in feet. 
The approximate maximum bending-moments previously determined for this ship are, 
for still water 5080 foot-tons, on a wave-crest 16,400 foot-tons, in a wave-hollow 31,000 
foot-tons ; the approximate maximum shearing-forces under the same circumstances are 
respectively 140 tons, 220 tons, and 395 tons. When ashore the maximum shearing- 
force is, of course, 1230 tons. By comparing this ship with the ‘■Bellerophon’ and 
‘ Minotaur,’ it will be seen that the maximum sagging-moment bears a larger ratio to 
the product of the displacement by the length than it does in the two ironclads. This 
is due to the fact, already illustrated, of the greater concentration of weights at the 
centre of the paddle-wheel steamship. 
These three examples afford us the means of approximating to the limiting values of 
the shearing-forces and bending-moments of ships supported at the extremities only, 
