The Virginia enterprise. [volume] (Virginia, St. Louis County, Minn.) 1893-19??, 1896-06-26
CHRONOMETER RATING.
Delicacy of Hearing that Can Detect 4
Difference of Tenth of a Second.

Delicacy of Hearing that Can Detect u
Difference of u Tenth of a Second.
There is nautical instrument shop
near the East river where nearly all the
thermometers of vessels striking this port
are left to be regulated. or rated, to use
shop is a resort for sea captains, and is
known the world over. The sailors call
it ''Negus'," and it is run by II. s. and
j. d. Negus at lao Water street.
Every large vessel sailing the ocean
has at least two thermometers, and all
the liners carry at least three, and many
of them carry four. A thermometer is
from the true Greenwich time it may be,
except when it is cleaned, and that is
only once in about three years. 1t is
rated instead. When the captain comes
into port he straightway takes his chro-
nometer to the shop. A record is made
of the time it registers. and it is com
pared with the true time at Greenwich,
Eng. 1t may be kept in the shop for
two or three days, or even in some cases
month \ careful record is kept to
determine whether the chronometcr is
gaining or losing time.
The average of all the observations
gives Il very accurate estimate of what
may be expected of the chronometer at
sea. Such is the skill of the chronometer
man that he can tell its variations down
to the tenth of Il second. \ large clock
in the shop ticks twice every second
Taking the chronometer to the big clock,
the operator listens intently to the tick
ing of the big clock and to the ticking
of the chronometer. and mentally notes
the difference. His ear is more accurate
than any instrument that can be made.
\ thermometer which neither gains nor
loses is something that has never been
built. Atmospheric and other variable
conditions affect it. SO that the feat is
impossible. 1t is this accuracy of the
ear that is the stock in trade of the
chronometer rater that cannot be pat
ented. copyrighted nor initiated. 1t comes
through long practice only. When the
job is done and the captain calls for
his chronOmeter he receives an exact
record Of what has been observed. n
record is as we'll kept in the shop.
No two of the thermometers on board
a ship may point to the same time of
day. They may vary several hours, in
fact But the captain knows just how
far away from the true time each one is,
from the ratings, and thus makes his cal
culationS. If his chronometer is five
minutes fast and points to half past ?,
he knows that the actual time is IS min
utes past ,. But the actual time is not
time me- since he Sailed. That is what the
chronometer is used to tell. Any old
clock will tell the actual time near
enough for all practical purposes.
Another odd feature of the chronome
ter is that Il dial on it's face shows exact
ly how long it has been wound up.
ChronOmeterS are wound up as regular
ly as farmer milks his COWS. They
will run tifty-siX hours, but are always
wound every twenty-four hours. This
is the kind most in use. Some chrO-
nometers will run eight days, but they
cost about $500. and are not much used
The common kind costs about $3.50. In
the Neguses' shop are constantly about
800 thermometers being rated. They
are wound at the same hour, and there is
more or less hustling in the place about
that time by all hands. 1t is no small
job to wind up 800 chronometers every
day. and it is a considerable part of the
office work.
1t will be seen that, as the records
are preserved in the shop, when once a
captain goes to Il given place to have
has rating done. he must keep on going
there all the time. This makes Neguses
go in there every day who have been
calling there for many years, every time
they are in port. Strange adventures,
odd experiences and novel tales are relat-
ed there. The rating done. the captain
takes his instrument, passes out, and
maybe will not be there again for several
years. When he returns he may have
tales to tell about the Chinese. the Malay
pira ties. or the cannibals of Australasia.
The captain he is talking to may reply to
his odd tales with recital of expert
ences i'll the Arctic regions.-New York
Sun.