The sun. [volume] (New York [N.Y.]) 1833-1916, 1896-03-22

fall back into line by abrupt or sudden move
menus. Any one who has had any military
training knows that IL is essential that the men
ssei do sltc .b sh iIns s IsstsS Ssry a SrSnSe,' y stT RI tnin rs
appearance, and the result IL that no. kind OF
line IL maintained. The officers OF q ship know
very closely It's speed from the number of .revo-
lutions Of the engine. For INSTANCE, on board
the New York the number Of revolutions of the
engine per minute divided by O gives, In n rough
way. the speed Of the ship In knota per hour.
30 revolutions making n speed of about 10
ssInins 70 or mi losing eSIn either rapidly or slowly, in.
stantly estimates what his speed ought TO be In
revolutions. In fact, he thinks In revolutions,
SO that what he needs IL an Instrument to tele-
graph revolutions.
The inrtrumcnts have to be lighted for night
use, simple ms this problem may appear, II has
really been one Of the greatest difficulty In the
practical designing and construction OF the
light at this point would be out Of the question.
for the reason that when an officer Is ON deck, at
night directing the moysm SI,S OF "a, snip ~ his
possibly como into c~ol,eion. None but the
feeLhest light Is permitted on the bridge, other,
wise his eyes would be da2zled. and lie would
be unable to see objects on the water in the dark
ness. The whole design and construction OF the
instrument had to be remodelled at least q score
of times In order TO provide for this exigcncy
without making the instrument too big and
The transmItter Includes two diafs Of solid
brass, mounted on one pedestal. each dial being
graduated to represent revolutions OF the en-
Gines. The pointer moving over the dial is at
tachcd to the lever which the operator moves in
adjusting the resistance to make n given signal.
Conveniently placed Opposite the centrr OF each
dial, and about three iupLsn distant, is an cleo
trio light ~ about one candle power. with u re-
Hector behind It and u hood over II. SO shaped rs
to throw n gentle glow on the scale and not be-
You'd IL. Each light Is in u wntcr-tight box,
and can be turned on or of 10y II. water
tight key. The transmitter, when com plotted. is
absolutely water tight, and may stand upon the
bridge for weeks and months together without
needing care. The receiver In the engine room
Is, In it's general arrangement, a duplicate of tho
transmitter on the bridge. IL encloses an ad-
Unstable resistance similar to that of the trans
mitter. When Its pointer is moved until the
galNanOmetcr comes to the zero mark, the scale
of the transmittcr will give the same Indication.
In the practical installation and use OF the ap-
paratus certain other features have TO be cOnsid-
cred. For instance. the men In the engine room
are busily employed. and visual Indications alone,
such as the movement Of n galvnnometcr. can
not he relied on To call their attention. For this
purpose a large bell is placed near the receiver
In each engine room. and this bell Is nutouat-
ically runE by the act of grasping the lever of
excellent point Of this instrument Is that 1t
gives control of both the starboard and
the port engine of tho ship from one trans
mitter. 1t is often necessary to run the
engines ut different speeds, or to stop one engine
entirely. Such control Is very easily exercised,
as tho levers for both engines and the ADJUST
able resistance which constitutes the signal ar-
parRtus for both are mounted on one pedestal.
The facility with which this can be done will be
appreciated by reference to the illustration.
which shows the officer in the act OF giving the
signal to back slow on the starbonrd engine.
and go ahead Slow on the port engine.