The Savannah morning news., 1900-07-05

strung a number of concentric perfora ed
discs. The perforations in the discs are
not parallel to the shaft, but have a nice
iy calculated pitch" The shaft runs
fore and aft. and the cupboard end pierces
the skin of the vessel, and carries the pro-
peller. The inboard part bearing the
discs, is encased in a metal jacket that
corresponds to the cylinder of the piston
engine, and is just large enough to re-
ceive discs and permit them and the shaft
TO revolve within 1t. Steam is adna tied
at the forward end of this jacket and in
passing toward the afterend. where 1t is
exhausted the only avenue open to it Is
by way of the pitched" or slanting per-
forations in the discs. The pressure of the
passing steam on the pitch turns the discs
and with them che shaft on which they
are hXed. There is no complicated net
work here of reversing levers. pistons,
links and eccentric5. A single valve
admits the steam; the Jacket concea,s all
the moving parts. A child may play about
the main engine without danger of being
caught up in plunging. whirling machin-
cry.
In these latest tests the two torpedo
boat destroyers have realized the marvel
Gus speed possibilities suggested by the
Iurblnia, the dimnutive boat with which
Mr. Parsons first surprised the world The
absence of vibration remarked in her is
remarked to an even greater degree in her
successors. The economic value of this
feature can hardly be overestimated. Vi
oratlon is one of the chief destructive
agents TO machinery and hull, and its
elimination must greatly increase their
me Economy of coal consumption is an
other advantage conceded to the turbine.
But in the Cobra. as in the Turbinia
there is serious drawback, the one that
seems " of no tnr Inn
dsplacing the piston engine on large
steamers. The turbine as now construct
ed is non-reversible; 1t can be driven In
only one direction. To make the Parsons
boats go astern a separate engine is at
tached 10 one of the four shafts and with
this makeshift the Cobra has attained
speed of about eighteen miles. The pub
lie could SCARCELY be persuaded to trust
itself upon liners steaming forty or more
miles an hour. but unable to reverse their
engines and stop quickly in time of dan
ger. Companies whose ships were still
equipped with the engines of to-day would
not be slow to point out the perils that
Turk in the steamship lanes for such
should turbine greybounds make their APP
pearance in competition for ocean passen-
ger traffic.
Still neither Mr.. Parsons nor those with
whom he is associated in perfecting his
system has made any eXtravagant claims
for it, Indeed, the inventor has at times
spoken rather disparagingly; he placed
the Turbinia at the disposal of disinter-
ested scientific men for thorough tests,
and the talk of three-day transatlantic
liners and other marine miracles that has
been heard in discussions of the Turbinia
have no warrant in anything he has said
about his invention But that there IS
confidence in Its great value is shown by
the insistence with which the British ad-
miraty conducts its costly experiments,
and the interest with which they are
watched by the scientific world at large.
The three-day boat is not here, or the
four-day boat still there is ground for
believing that the turbine principle is
soon to have a trial at ocean crossing and
its development is now so far advanced
that a notable performance can scarcely
fail to result.