employment oj Oblique Riders. 327 
be considerably weaker than this, and the other parts of the 
ship considerably stronger ; but since the fastenings appear to 
possess sufficient strength to resist any strain which is actually 
likely to affect them, there seems to be no inconvenience in 
their inferiority to the other parts. In fact, the Tremendous 
actually supported, for three days, without any perceptible 
change of form, a strain fully equal to that which is here cal- 
culated, having been purposely left on shores, which extended 
through 52 feet only of her length. But it must be re- 
membered, that such a force, from its very gradual application, 
must be much less trying to the ship's strength, tiian the more 
abrupt changes which occur at sea, and it must on the wliole 
be inferred, that it would be unsafe to trust to the braces alone, 
unsupported by the cooperation of the neighbouring parts. 
It would probably be easy to add some further strength to 
these braces near the ends of the ship, where the strain on 
them is the greatest, especially about 30 feet from the head, 
if it were found that they gave way before the rest of the 
timbers ; and it might also be possible to replace them, if they 
sion or extension of the brace will be to the descent of a weight connected with the 
moveable end of the parallelogram, as the depth of the parallelogram to the length of 
the brace, w'hatever the actual distance of the weight may be ; so that although the strain 
on the horizontal pieces increases with this distance, that which affects the brace is in- 
dependent of it ; the relative being to the absolute strength as the depth of the frame 
is to the length of the brace. We must therefore inquire, what is the greatest absolute 
force that can be supposed to urge a given portion of the fabric in cither direction : 
thus the excess of weight w'hich has been attributed to the bowsprit and the neigh- 
bouring parts being 192 tons at ipf feet from the head, this force may be occasio- 
nally increased by a similar pressure derived from the effect of the waves, which aloiie 
would amount to 302 tons at feet ftom the head, and which may sometimes 
cooperate with the former, so as to constitute a force of about 450 tons, about 25 
feet from the head. 
UU 2 
