The republic. [volume] (Washington [D.C.]) 1849-1853, 1849-11-06
The screw and the Paddle.

The Screw and the Paddle.
The following article on the comparative
merits ofthe screw and paddle wheel as in
struments Of propulsion for war-steamers,
we copy from a late number of the Plymouth
Herald The pioneer war-steamer on the
screw principle was our own Princeton;
and it has been matter Of surprise that,
while the English and French govern
ments have been reproducing that vessel
in various notifications, the American
navy is yet without copy or second of
it. All the English engineers, we OBJ
serve, unite in giving credit to Captain
ERIcssoN, the inventor and constructor
Of the steam-machinery Of the Princeton,
for the practical introduction of this mode
of propulsion; and President TYLER is
entitled to the commentator of having
taken up the invention and causing it to
be put in practice in our navy, at time
when it was regarded with no favor by the
British admiralty.
Some credit is also due to the late adj
ministration for the interest it manifested
in the cause of science and art by the
promotion and encouragement Of the men
distinguished in those walks. 1t will be
matter of serious disappointment to the
country, if the party now in power fail to
surpass the men they have supplanted, in
fha met anco,ra ra poapf and raward of
eminent talent in the various departments
Of invention. The day has gone by when
it was esteemed the province Of govern
ments and the public to plumber men Of
genius Of the result of their labors-though
the fate of Whitney and Fulton proves
that it was once thought no hardship to
make public appropriation of individual
property, and to "whistle down the wind"
the meritorious authors Of great public i'm
provements.
From the Plymouth Herald
The Basilisk and Niger steamers lately returned
to Hamoaze, after weeks trial of the comparative
merits of the paddle and the screw as machines for
propelng Ships and it has been found that in these
vessels, (Which possible alike in form,
horse power, and sails,) the screw is equal to
superior TO the paddles, whenever the respective
boilers of the two vessels generate equal quaint
ty of steam at equal density. The boilers of the
two vessels very unequal in power for general
ing steam, there being deficiency board the
Niger vessel, where, the machinery being
fixed in her bottom, beyond the reach of shot, her
tubular boilers are SO low that the fire has to de-
~. TAX NJ, ,,,To. ,aol
that in the higher parts of the boilers there is an
cess of heat, but in the lower parts deficiency,
and hence the want of steam and a waste of coal,
which better arrangement of the hues might OBJ
yiate. These experimental trials will be Of great
value, and in the end prevent unnecessary expense.
The facts obtained are--l. That whenever the two
vessels engines work up to the same amount Of
horse power, the screw propeller obtains the high
est velocity. 2. When the vessels are fastened
stern TO stern, the screw has the mastery the
paddles, by dragging the paddle vessel stern fore
most. 3. The screw and its necessary machinery
entirely under water, and thereby protected
from shot, whilst the paddles and machinery are
very much exposed. 4. The paddle vessel mounts
six guns whilst the screw vessel mounts fourteen
guns. S. The Niger has great superiority as a sail
ing vessel over the BasiIisk, and in no circum-
stances would be in danger by loss Of machinery,
as is the case with paddle vessels on lee-shore.
The power which the screw propeller transfers to
the helm is of primary importance in ships of
war, by quickening maneuvres in confined spaces,
whilst the paddle vessel requires great space as
three-decker TO turn in. Independent, then, Of
other manifest advantages, such a broadside Of
artillery, double capacity for sails machinery,
(and the machinery being under water,) which
the screw vessels possess, the power of quickly
turning would, or rather should, lead us TO give
preference TO the vessel propelled by the screw for
purposes Of war, or for long sea voyages, which
might be made without the aid Of steam at ALL and
with the same celebrity as the ordinary sailing
eel