Jhr the Circidar Skrns SJilps qf War. 
of no, small extent was necessary, before they could be consider- 
ed again fit for service.’’ 
To contrast more clearly the defence of a circular stern with 
one of a square form, we may refer to Fig. 2. where it appears,, 
that although the guns at the ports A and B may be trained to 
the greatest angles which tlie situations of the ports will adnyit 
of; yet the arc XY, comprising from 40° to 50°, will be en- 
tirely without defence. A similar defect, it is apparent, must 
exist oh the other quarter of the ship. In fact, the only part 
of the square stern that can be well defended, is the arc YZ, 
comprising about 40°, the remaining part being entirely without 
defence. In the former figure, it was proved that no part of 
the semicircular sweep round the stern was undefended. 
“ In the event of future wars,” observes Sir Robert, “ art 
alteration in the form of the stern of our ships of war would in 
all probability be absolutely necessary,^ by which the guns may 
be worked with greater effect and facility, in consequence of the 
introduction of steam-vessels ; and that America is firmly con- 
vinced that a system of attack, by this description of vessels, is 
not only practicable, but that it will also be destructive in ita 
operations, is not to be doubted. Indeed,” continues Sir R. 
I have been told, from good authority, that they have lately 
well manned one of their frigates, given the command of her to 
a. good officer, and directed an experiment to be tried, if a ves- 
sel propelled by steam could not, under any circumstances, lay 
on the quarter of the ship she attacked, and tlie result was com- 
pletely in favour of tlie steam-vessel.” If vve inquire into the 
cause of this failure, we shall undoubtedly find, that the frigate 
was incapable of defending her quarter^ owing to the square form 
of her stern,— a circumstance which would not have taken place, 
jf slie had possessed one of a circular form. 
In case of an attack of the kind: just alluded to, Sir Robert 
Seppihgs’ plan gives a superiority, not only on account of the 
additional number of guns which the ship is enabled to bring 
into action, and the sweep of the 'ocean which those guns are 
able to command, but also an advantage of another kind, arising 
from the diminution of the distance of that point from the shi|) 
where the shot: from the two after guns cross each other, when 
the guns are trained to their greatest angle, — a point, it is pre 
