Washington sentinel., 1854-02-05


shafts, paddle-wheels, and paddle-boxes would
be entirely dispensed with.-N Y. 7ti6une.
In reference to this subject the Scientific
american says:
We have published the above to point out
the want of correct information contained in it,
in relation to the application of force in pro-
pulsion, in order that none of our people may
be led astray by the principle described and
the incorrect statements made.
" Three distinct things are pointed out in the
above first, the vessel is propelled by the re-
action Of a column Of water; second, this water
leaves the exit tubes at a great Uelocity and
above the water-leyel third, this vessel, with
the same amount of fuel, can be propelled one
third faster than the Collins steamers. 1t is
not true that vessel propelled in this manner
could cross the ocean in one-third less time, as
stated, than the Collins steamers but it must,
from the very nature of the. means of propul-
sion require twice the time Of one of the Collins
steamers to run from New York to Liverpool.
"The employment of water as propelling
agent for steamboats, is not new it was among
the earliest plans proposed, and is theinyention
of James Rumsey, of Virginia-see an engrav
ing of his boat, on page III, vol. 5, Scientific
american. To get the full value of the re-
active force Of water in propulsion, it the
water) should leave the tubes without velocity;
consequently there is great loss of power in the
arrangement described above, as all the yelo-
city contained in the discharged water is a waste
OF force. The greatest amount of velocity that
can be obtained by vessel propelled by the
reaction OF water is only SO per cent. Of the
power applied. The whole science of mechani-
cal engineering is founded on the remark attri-
h,fo1 70 Aroh IT,, x1o
on to rest my lever, and will raise the world"
To propel any machine or carriage economi-
cally, a fulctum for the lever is the first grand
desideratum. If steamship can be economi-
cally propelled by the reaction of column Of
water why not at once, without the use of
pump for such a purpose, propel it with the re-
active force of the steam, and why not propel all
our locomotives in this manner? The reason is
obvious a firm fulcrumfor the propelling lever
is required to do its work economically, and this
lever must be rigid substance, not fluid. IF
we could suspend cannon by a single thread
of silk, and use ball of the same weight as
the cannon, the latter, if its form was as favor
able, would be propelled backwards as far
as the ball would be projected forwards. This
would be the effect, according to the law, "ac-
ton and reaction are equal" A man standing
on floating board cannot lift weight to the
same height as he could if standing upon terra
frma. Every person knows this to be true
"Thepropelling water, therefore, in the Messrs.
Ruthven's boat, is projected into the air as into
a sheath, and there is no proper resisting me-
dium by which all the velocity Of the water is
applied to propel the boat If the exit tubes
were as large as the inlet tubes, no velocity
would impaired tothe vessel, because thewater
would leave the vessel as freely as it entered it.
The whole amount of velocity obtained is due
to the difference of the area, then, of the inlet
and exit tubes. This arrangement, therefore,
must involve great loss of power The boat
seen by the above correspondent may be very
useful for some purposes, but it does not econo-
mize power; neither is it so simple for revers-
ing the motion Of the vessel as a paddle-wheel.
There is one good arrangement of the nozzles-
that is, the employment of. one when required
to turn the vessel, as can be done by single
oar. The idea is not new, as it respects paddle
wheel steamers but it is not so easily carried
out in them. 1t is time that the value of a
firm fulcrum for moving bodies was better un-
derstood. A steamship can never be propelled
with the same economy of power as locomo-
tive; and for the same reason balloon can
never be propelled with the same economy of
power as a steamboat. Every person is ac-
quainted with these truths; they are applicable
to all conditions and operations of bodies. Thus
we expend more power in walking over swampy
ground than on a smooth hard road, because
the former is yielding fulcrum to the force of
propulsion, while the latter is a firm fulcrun.''