Tensas gazette. [volume] (St. Joseph, La.) 1886-current, 1918-03-22
War Causes Shortage of Chro-
nometers Used in Ocean
Navigation.
none IN THE OPEN MARKET
Price Jumps From $500 to $500 and
Over-EngIishman Who Perfected
instrument Won Prize of $780,.
600 and Thanks of Mankind.

MISUNDERSTANDING the busiest
people supplying the United States
with war materials are the makers of
chroh0meters. Great care and pre-
clsion are necessary in turning out
these navigating Instruments, which
are the most accurate portable time
keepers known to science.
Hundreds of thermometers have gone
10 the bottom of the ocean since
the war began. This alone would
cause shortage in the ordinary sup
ply while the equipping of the new
American merchant marine is creating
an unprecedented demand for new in
struments. Each of the 1000 ships to
De ADDED to the national cargo-carrying
heet under the shipping boards con-
struction program. will carry two and
many of them three chronometers.
At present there are virtually no
chronometers to be had i'm the open
market. Before the war England SUD-
pied the world with most of its fine
chronometers. ChronOmeters are also
maze In America, though the English
type still Is most esteemed by sailors.
In ordinary times a good chronome-
Ter costs about $500. The present price
Is SoVO or better, according to the trade
maze. The supply in this country
passes through the hands of few ex-
perts. who are doing their utmost to
meet the demand. and to expedite the
output of the manufacturers.
FROM six months to year and a
half are necessary to make and adjust
a chronOmeter. The mechanism is of
the finest metals, and specially adapt
cd 10 resistance to extremes Of tenn
perature. A high-grade chronometer
VIII Keep just as good time If kept in
cold storage six months as in ordinary
temperature. while q voyage I'm the
tropics will not seriously change its
time-keeping qualities.
In appearance a chronometer is a
small, metal-faced clock. 1t is kept in
q wooden case, usually of mahogany.
and is swung on gimbals, to keep 1t
always on level. 1t is sensitive to
rough handling, and care is always
taken not to jar 1t.
Errors Are Noted.
No clock or watch has ever yet kept
perfect time, so there is always
slight gain or loss to a chronometer.
For this reason the chronometers rate
of daily gain or loss is determined by
observation ashore, and card show
ing the rate is made out, and deliv-
cred with the instrument. This rate
of error is allowed in all notations of
time made from the instrument for
working up observations made at sea.
A gain or loss. Of second a day is
considered i''large rate" for a good
instrument.
: Tha-abrdhometer completes, with
the compass and sextant. the trio of
indispensable instruments required in
modern navigation. BY its aid, lOngl- |
tu1e, or the east or west position of a
ship, is determined.
Longitude baffled all navigators I'M |
til the chronometer came into use in |
1735. The ancients and later naviga- |
tors, including all the great discover
ers, could find their latitude by OBJ
servations Of the suns height. but they
could determine their longitude only
by dead reckoning" or estimating
their ships progress from day to day.
This system was uncertain, and
caused a great many shipwrecks.
Longitude is merely the difference
Of time between two points on the
earth's surface, and 1t became appar-