1866.] Be 
II. CONSIDERATIONS ON THE LOSS OF THE ‘LONDON,’ 
By Wii11am Farrsarrn, C.E., F.RS., &e. 
THe introduction of iron as a material in constructive art has 
been attended with great advantages. or the purposes of ship- 
building it has given greatly increased strength, and afforded 
facilities for obtaining new forms, which, aided by the power of 
steam, have ensured a rate of speed in vessels never before attained 
in naval history. It has, moreover, furnished the naval architect 
with a material of immense value as regards construction, and its 
careful distribution in the shape of ribs, frames, and the sheathing of 
vessels cannot be too highly appreciated. As compared with the best 
English oak, it exhibits four times its powers of resistance, and it has 
in addition the double advantage of being almost perfectly homo- 
geneous and free from the defects of open joints, which in the case of 
the planking of wooden vessels require to be caulked. With all these 
advantages, iron constructions are surrounded with many dangers 
when entrusted to the care and superintendence of incompetent 
persons ; in such hands there invariably exists a want of proportion 
in the formation of iron vessels, which exhibit defective powers of 
resistance, and such other abnormal conditions as might prove 
destructive to the efficiency and ultimate security of the structure. 
It is therefore necessary that the naval architect or builder should 
be conversant with the properties of the material employed, 
whether considered separately or in combination, and moreover, 
he should be satisfied that the vessel, when finished, is capable of 
permanently resisting the forces of tension and compression, and 
all the varied strains to which she is subjected when afloat. 
In laying down the lines of a ship, all these conditions should 
be carefully and deliberately considered. It is also of importance 
to take into account the forms or lines of least resistance, such as a 
fine entrance at the bows, and an equally clear run at the stern, if 
high speed is the object to be attained. In such cases, these forms 
are highly advantageous for vessels navigating rivers and smooth 
water, but in those intended for long sea voyages, and having to 
contend with the waves of the Atlantic or the rolling seas of the 
Cape, it is questionable whether or not some slight sacrifices should 
be made to speed, and some modification effected in the form of the 
bows and stern, in order to meet all the requirements of a safe and 
convenient vessel intended for the double purpose of carrying 
passengers and cargo. 
I have been led to these particular considerations, not so much 
from*the lamentable accident which overtook the ‘ London,’ as from 
the conviction, that the safety and success of a vessel does not depend 
so much on its speed as upon its sea-going properties and sound con- 
