1874. | Loss of Life at Sea. 485 
power to carry deck loads would often be useless; thus on 
an 800-ton steamer it depended to keep up communications 
with the army in Kaffraria and the colony, to throw in rein- 
forcements, provisions, horses,and munitions of war, carrying 
sometimes as many as 8o0 levies with their stores and pro- 
visions, and this allon deck. Yet this vessel was proverbially 
an easy vessel. Numberless instances of the necessity for 
such a property could be given. 
It may be affirmed also with confidence that various 
exigencies occur when such a power is necessary in merchant 
ships, such as taking crews off sinking vessels, and yet no 
such power was provided for in the many ships that have 
capsized because of their having deck loads. 
It may be said that we object 77 toto to double bottoms, 
though they are necessary, because the thin iron skin is 
more easily perforated than is the wood planking of wood 
ships. 
We do not object to any proper use of a second or inner 
bottom, to make iron ships stronger and safer against 
injuries from taking the ground or from torpedoes, or to 
facilitate repairs : such ships require it, as their bottoms are 
far less strong and less calculated to bear injury than those 
of wood ships; and we doubt not those iron vessels, with 
deep iron bilge-keels, will be specially liable to damage ; nay, 
more, that these very keels on taking the ground in many 
cases will serve to tear a large portion of the lower bottom 
out, if they do not injure the inner or upper bottom through 
the frames, thanks to the little-stability system smuggled 
into the navy to ‘‘ check rolling.” 
We do, however, object to raising these inner bottoms 
unduly for the purpose of raising the centre of gravity from 
an idea that it is wise to do so. 
We object to making the bottoms of vessels light, on the 
grounds of cheeseparing parsimony, and then assuming that 
this makes no difference in the properties of the vessel, that 
the bottoms are equally heavy, though empty, with all 
other parts of the immersed body, even when they are 
crammed full, and then assuming that the results of calcula- 
tions made on such an hypothesis can be otherwise than 
erroneous, deceptive, and proportionably dangerous. ‘That 
they are so we have proved in pages 34 to 44 of ‘‘ Our 
Tronclads and Merchant Vessels,’”’* and need not repeat it 
mere. 
We have also demonstrated that in proportion as the spaces 
* Our Ironclads and Merchant Vessels, by the Author. Harrison and Sons. 
VOL. IV. (N.S.) 3Q 
