Evening star. [volume] (Washington, D.C.) 1854-1972, 1907-05-08
ENGINEERS TAKE TRIP
MEMBERS VISIT AND INSPECT
BUREAU OF STANDARDS.

Members of the Washington Society Of
Engineers, to the number of about 100,
visited the bureau Of standards last evening
to inspect the equipment and apparatus.
The heads of the various bureaus were
present, and as small parties called at each
OF the separate divisions the chief ex-
planned the instruments in use and their
object. The party visited all floors Of the
physical, mechanical and low-temperature
laboratories.
The liquid-air plant and experiments with
that substance proved interesting Liquid
air is made at the bureau with small
machine, which first congresses the air
and then allows 1t to expand in very cool
chamber. The cool chamber Is secured by
allowing carbon dioxide, under pressure, to
expand. The machine Is about seven feet
high. Supported by iron work is a steel
cylinder about two feet high and about
two feet in diameter. The air Is liquefied
inside of that and drops down into glass
vase underneath the cylinder. Many of the
party mstook 1t for water at first.
Experiments with the liquid air included
the freezing of mercury and alcohol. Sew
eral of the party put their fingers into the
liquid air and said that it was not cold, al
though its temperature was about $50 de-
grees centgrade below the freezing point
of water. 1t was explained that the finger
Is so hot that it makes the liquid air Doll
formed keeps the liquid air from coming in
contact with the finger.
In Mechanical Laboratory.
The mechanical laboratory was next visit
ed. In the basement were found the engt-
neering plant, boiler room, engine and dyna-
mo room, refrigerator room, storage bat
teres and ventilating apparatus. From the
refrigeratng room, it was explained, sew
eral CT the rooms in the buildings used by
the bureau are cooled in summer AS a
matter of fact, no direct effort Is made to
cool the temperature but the apparatus
in the rooms is designed to take out the
MOISTURE in the room. 1t has happened, 1t
was explained, that the temperature Of a
room actually rose, but that the removal of
the moisture in the air made it seem much
cooler. 1t was stated that such cooling
plants are practicable for dwelling houses
or office buildings.
The first and second floors Of the build
ing are used for testing electrical measur-
ing instruments. engineering instruments
and materials, such as iron. building mate
rails of all kinds, cement, etc, and for ex-
perimentS with magnetism and photometry.
One of the interesting tests now being
made Is to determine classification of lead
pencils. 1t Is explained that pencil makers
have classfications Of their own, based on
the chemical makeup of the lead; but 1t Is
desired to establish classification on the
basis of hardness and durability, which can
be applied to all pencils and which the gov
eminent can use in its purchase of pen
ellis. No definite results have yet been
reached.
The physical laboratory the largest of
the three buildings, is used for the testing
of surveyors tapes, weights of all kinds,
efficiency of various kinds of lamps, chiefly
electric, etc.; and 1t also proved of interest
to the engineers.