APRIL II, 1907] 
IAT Tees 
23) 
61 
GYROSCOPIC APPARATUS 
SHIPS. 
ce our account of the recent meeting of the Institu- 
tion of Naval Architects (Nature, March 
p- 522) reference was made to the paper read by Sir 
William White in which he gave particulars 
certain experiments carried out on the estuary of the 
Elbe by means of a torpedo-boat, the Seebar, in 
FOR STEADYING 
which Dr. Otto Schlick’s gyroscopic apparatus was 
In our report of the meeting we stated that 
fitted. 
28, | 
of | 
this end he acquired the Seebar, formerly a first-class 
torpedo-boat, 116 feet long, 11-7 feet wide, 3-4 feet 
draught, and of fifty-six tons displacement. Her 
metacentric height was 1.643 feet, and her period of 
oscillation (double roll) 4-136 seconds. Into this 
vessel was fitted the gyroscopic apparatus, of which 
we give a sectional elevation in Fig. 1. The 
following are the main particulars:—the outside 
diameter of the fly-wheel was 1 metre, the weight, 
without the spindle, 1106 lb., and the peripheral 
velocity at which it was run 274.8 feet per second, 
the number of revolutions being 
1600 per minute. The fly re- 
volved on a vertical spindle, and 
was of forged steel; it was en- 
closed in a cast-iron case, the 
latter being supported by two 
hollow trunnions, the common 
axis of which was in a ’thwart- 
ships direction, as shown in 
Fig. 1. It would have been pre- 
ferred to have used _ electric 
power to revolve the fly-wheel, 
but as generating machinery was 
Fic. 1.—Details of steadying apparatus on s.s. Seebar. 
we should return to the subject, and this we now 
proceed to do. 
It may be remembered that three years ago Dr. 
Schlick read a paper at the spring meeting of the 
same institution on the gyroscopic effect of fly- 
wheels on board ship, and at the same period he 
illustrated, by means of models, the system of steady- 
ing vessels which he had brought forward. The 
models were, as Sir William White 
pointed out, of small inertia com- 
pared to the inertia of the gyro- 
Scale about 1/2sth full size. 
not fitted it was determined to 
use steam direct, and for this 
purpose blades were fitted to the 
periphery so as to work the fly- 
wheel as if- it were a turbine, 
steam being admitted through 
the hollow trunnions. For this 
reason the peripheral speed was 
less than it would have been had 
electricity been the motive power, 
and the weight was consequently 
greater for the production of an 
equal gyroscopic effect. 
It will be assumed for the pur- 
pose of this description that the 
principle of gyroscopic action is 
known so far as it is generally 
those who wish to refresh their 
memories on this matter would do well to refer 
to Dr. Schlick’s paper in the Transactions of 
the Institution of Naval Architects for 1904. The 
common centre of gravity of the whole apparatus 
was, in the Seebar, below the axes of the 
trunnions with the vessel at rest, and the spindle 
therefore vertical. On rolling motion being set up 
understood, but 
17% JULY 1906 
scopes mounted in them, and the 
steadying effect was, therefore, 5 
more marked than it would be % 
under the conditions of ordinary ™ 
working with ships or boats. In 
these circumstances it is perhaps 
hardly surprising that a good many ¢ 
persons connected with seafaring 2 
looked on Dr. Schlick’s apparatus 3 
as outside the region of useful “ 
application; in fact, it would not 
be an exaggeration to say that the 
idea was largely considered to be 
a very pretty scientific *‘ fad.” 
Dr. Schlick, though a man of science, is by no 
means a “ faddist ?; as the position he holds in the 
German mercantile marine, and the substantial con- 
tributions he has made to the advancement of marine 
engineering practice sufficiently show, and he deter- 
mined to prove the soundness of his theoretical in- 
vestigations by experiment on a practical scale. To 
NO. 1954, VOL. 75] 
Fic. 2.—Diagram of Oscillations of s.s. Seedar. 
the spindle would be free to become inclined from the 
vertical in a fore and aft direction, and, as rolling 
proceeded, the gyroscopic effect of the fly-wheel would 
produce longitudinal oscillations of the apparatus 
having a period depending upon the distance of the 
centre of gravity below the axes of the trunnions 
and upon the moment of inertia of .the apparatus 
