The daily gazette., 1877-06-11
From the Baltimore Sun.
Measurement of Time.

A question has been lately addressed to
us as TO the ancient mode of the measure
ment of time. Water clocks have been
in use in the East for about two thousand
years. These have been gradually i'm
proved to this present period. The sub
stitution of a weight for the water to .urn
the wheel is supposed TO have been the
work of the Saracens, though 1t may have
been introduced some time before, for Ar
chimedes had discoveredthe advantages Of
weight in the turning of small machines
some centuries earlier. The clepsydra-
supposed to have been used among the
Chaldeans, was employed extensively by
the Greek and Romans. This instrument
measured time by the gradual flow Of
water through small orifice. 1t is still
used in China, and anciently had in some
instances a musical attachment, by which
attention was called to the hour as by the
stroke of a bell in our clocks. They
were introduced in Rome about 15S B.
q. Eighteen years later they were i'm
proved by the addition of tOothed wheel
and index driven by the water which
flowed from the bottom of the jar. Then
came the substitution Of the weight as has
been already mentioned.
AT very carly period men began to
divide the day into several portions, and
soon the night also. The3e divisions
were at first of about three or four
hours each, but after lime the di vision
of night aud day into twelve hours
each was found to be more coLven-
lent, aud then there came the necessity
for means of measuring each of these
divisions of time. The first in use was
the dial, the use Of which was learned by
the Greeks from the Chaldeans. This
instrument shows the hours of the day
the shadow of a gnomon OF style cast by
the sun or graduated arc. The object
in the construction of dial is TO find the
suns distance from the meridian by
means of the shadow. This being known
the hour also is known. 1t is true that
shadow can never be so well defined that
its limits can be ascerlained with astron-
omicsl precision. Practically the error
may not be of great account. 1t is be-
lieved that the style or pin Of the sun dial
which by its shadow indicates the hour
of the day, was probably the first astro-
nomical instrument, aud it apears to
have been in much use among the
Egyptians, the Chinese, and even the
Peruvians.
1t is not necessary to trace the history
of the clock from the time of the substi-
tuition ofa weight for water to turn the
toothed wheel. Various difficulties in
the construction were afterwards rectified
The ingenuity of our own countrymen
has been exercised in bringing the clock
to its present state of perfection. The
clock, as has been justly said, was the
mother Of the watch. When,it was made
in 1477, by Peter Hele, q clockmaker Of
Nuremburg, it was called the eliminated
egg" and was considered one of the won
ders Of the world. The production of this
p cketclock" cost ayear'slabor ;wasabout
the s.ze and shape Of goose egg; varied
nearly an hour day from the true time,
and the price was equal to about 81 500
in gold Of to-day. 1t is needless to trace
its improvements from that period to the
present, but as in the clock, so in the
watch, the American makers are now
competing successfully with all others in
the markets of the world. Chronometers
are wal ches adjusted to the variations OF
temperature, and many of Ameriei n
make have proved as accurate as any
timepiece ever made.