New-York daily tribune. [volume] (New-York [N.Y.]) 1842-1866, 1859-12-03
SCIENCE, INDUSTRY, AND INTENTION.
OCEAN STEAMSHIPS.

Though steam navigation is undoubtedly yet in its
infancy, and the economy and speed acquired small
when compared with the possibilities of the future,
one requires little conservatism to be disguised with
the extrayagant and unphlosophical pretensions of
some of our marine wseacres
Hydrodynamics is an abstruse science, and remarka-
bly, perplexng in its application to practical purposes,
so much 30, that j. has been but few years since
the first purely scientific water-wheel was con-
sructed and this application of principle long under
stood was the result of mere accident.
The force of moving water is now almost entirely
saved leaving but little for improvement in its
application motive power; but previous to the
r clipper ships the resistance of inertia in the dis
placements of vessels appeared to be wholly dsre-
garded, builders directing their attention mainly to the
greatest possible tunnage within the least possible area
of hull. Since ideas communicate by lightning and
travellers by the rail- necessity arises for more rapid
transportation where these eonvenences cannot be ap-
piled: hence clipper ships fast dspacng the older
models and in steamboats, and ocean steamers additional
speed is effected by less resistance Two inherent diff
culties existing in steam navigation render il impOs-
sible to acquire great speed without enormous con-
sumption and lose of power while with slow motion
and level surface it is the most favorable Of all means
Of transportation.
AS ship in going her length, dsplaces quantity
of water just equal to the bulk of her hull below the
water-line the power expended does not necessarily
depend the weight and velocity of the ship, but
the weight and velocity Of the water being displaced;
and this depends both on the velocity of the ship and
form of her hull The greater the distance from her
bow her greatest width the slower the velocity of
the water in proportion to her own speed. Thus it is
seen, that for great speed ship should be built with
great length in proportion to her width possible
this disparity being limited only by width sufficient
TO insure strength, room for cargo and make her
ageable. But great length in proportion to breadth
is only point gained in favor of speed; she should
also be so constructed as to give the water no more
motion than is necessary, leaving it at her sides in
state of rest; and the law governing the flow of water
into q vacuum should be considered in modelling the
stern to insure smooth and easy contact as the
water is being replaced at her rear.
A mathematical calculation made in strict accord
ance with he laws Of hydrodynamics will give the
outline of ships hull, which, at given velocity would
scarcely cause an eddy or ripple; but az a perfect
model can only be made for given velocity prac.-
cally only an approximation to perfection can be at
taued Aside from the resistance Of the atmosphere
the speed of locomotive is in exact proportion TO the
power applied, while with ship the power applied is
the square of the velocity the after getting
under way having only friction to overcome, while
the other is constantly overcoming inertia and though
the velocity of given weight is the power APPLIED
IN ship doubles her speed, she twice the
weight of water with twice the velocity thus requir
ing four times the power.
Again: all steamships, whether side-whee or pro-
PETERS must necessarily sustain considerable loss Of
power by giving motion TO the water used as full
crum or resistance for the wheels that increased
speed, acquired by increased velocity of the wheels
would force back greater weight of water, costing
an additional lose Of power. Theoretically, the great
est economy in power, requires the paddles or prope
Ter wheel 10 take such hold on the water az to move is
imperceptiby, but practically medium is found to
give the maximum result.
The lines of every portion of the hull of a ship be-
tween her water line and keel, part the and
leave at her sides in state Of rest should consist Of
curves the form Of each depending on It's distance
from the keel and the velocity with which she Is 70
run.
STEPS are now being taken in Buffalo by the Hon.
Millard Fillmore, the Hon. S. G. Ravens and other
wealthy and influential citizens to carry out an imprae
ticable proee; for ecpsng the Great Eastern by an
American Levia,han, description Of which we clip
from exchange
The new ocean steamship which il il proposed 20
build al Buffalo TO travel one hundred miles an hour
is TO be Of the following dimensons
length tthTeequartsrs Of niIeD .........4OOo feet
idth..'........
Each end Is 10 be constructed alike in the form of
wedge. This wedge form is l. $50 feet long, leaving
The parallel portion 500 feet in length To steady the
vessel lns are attached 500 feet Iong each OF the
ends. These fms impar strength possess great buoy
for he of znrfae ~