The Rock Island Argus and daily union. (Rock Island, Ill.) 1920-1923, 1922-05-22

Washington, D. c., May 20.-Ii
you get short weight on meat OF
Strawberries at the corner grocery
it is not because Uncle Sam is I'M
able to produce accurate weights
and scales. At the United States
bureau of standards government
scientists can weigh name writ
ten on a sheet of paper. They can
even add a period otter the sigma
ture and weigh that And the same
precision may be applied to weigh
ing on a larger scale. IL it were
necessary, the apparatus could be
provided to weigh a 25,000-ton bat,
tleship so accurately that even the
sbsence of even one-pound rivet
could be detected.
Back in 1890 the two national
standards, two little kilogram
weights each containing $4,000
worth of platinum and iridium
were brought to this country un-
der seal and opened by President
Harrison. They had been made by
order of the international weights
and measures conference at Paris.
Each country represented received
two kilogram weights, and the two
original weights from which they
were made were deposited at Paris
in a vault guarded by three sep
arate locks. The presence of all
three Of the officials who keep the
three keys to the vault is required
whenever these two most valuable
weight standards in the world are
consulted.
Since the bureau OF standards
was established our two national
standards have remained there,
locked in a vault. No one touches
them with his fingers. One has
been used a few times in the last
80 years, but it is always handled
with chamois covered pliers. The
other had never been taken from
the vault until test was made the
other day because the scientists
wanted to find out whether the
standard that had been used was
affected by handling. They also
wished to compare the secondary
standards which are more gener-
ally used about the laboratories
with the national standards.
The test showed that the national
standards have not changed appre-
ciably during their 80 years exist
ence. Other weights also showed
changes SO slight as to be unim-
portant. The largest change in a
klogram noted by the delicate ap-
paratus of the government labora-
tory was one ten-millionth This
weight had been used for more
than so years.
This was serious work because
the weight standards of the coun-
try are of tremendous Importance.
They are the best weights made,
and they are the basis of the
weighing that goes on in markets,
stockyards, shipbuilding plants and
factories. They are rarely used
because the government does not
wish to endanger their accuracy by
handling them. They are only to
be taken out at long intervals, as
they were the other day, to make
sure that the country is operating
on sound weight basis.
Precaution Observed.
The layman generally thinks that
he is weighing carefully when he
holds his breath and steadies his
hands as he slides the weights on
the bar. That may be careful
enough for ordinary purposes. But
the bureau of standards sets the
record for extreme caution in
weighing tests. Watchmakers, dia-
mond merchants, pharmacists and
research workers who use fine and
accurate balances send their
weights to the bureau to have them
proved by government standards.
The balances in the government
laboratory are in glass cases. The