Pittsburg dispatch. [volume] (Pittsburg [Pa.]) 1880-1923, 1890-10-11
STANDARDS FOR ANALYSIS.
Prof. Langley, Formerly of This City, Tells
of the Work of the American Committee
Important Discussions Pertaining to
DOubIe Chloride SoIutions

Prof Langley, Formerly of This City, Tells
of the Work of the American Committee
Important Discussions Pertaining to
Double Chloride Solutions.
Prot. John W. Langley read an interest
ing compilation of facts and figures on the
International Standards for the Analysis
of Iron and Steel. His paper was as follows:
In the summer of 1883 1t was the fortune of
the writer to present the subject of the desra-
biity of establishing set of samples of steel,
which should be analyzed with extreme care, i'll
order that they might become standards to
which scientific and commercial analyses of
iron and steel could be subsequently referred.
Also, that greater uniformity in the results of
analyses might be brough: about, since these
standards would bear toward analytical meth
DDS somewhat the position which the original
units of weight and length, the gramme and
meter, or the pound and yard, preserved in
Paris, London, and Washington, do to the me-
chanical arts.
An lngot of tool steel, 31S inches square,
poured from single crucible. in which the
metal had been thoroughly dead melted"
was heated and hammered barely enough to
round off the corners. The Ingot was then cut
into two pieces, one of which was then re-
heated and hammered down to bar 15zx54
inches.
PITTsBURG MATERIAL WAS USED.
The other half OF the ingot was turned in
lathe with a blunt tool exactly as in the manu-
facture of the international standards. and the
turnings. after sitting from fine dust. were
thoroughly mixed and then sealed up in glass
jars. The hammered bar was drilled and the
drillings similarly treated. This material was
given by the Crescent Steel Company, of Pitts
burg The object OF this was to have two
bodies of metal presumably identical in origi.
large amount of mechanical work. the other
approximately none. These samples are desig-
mated exp. standard, ingot exp. standard, ham,
mered, respectively.
The apparatus used by Dudley consisted of
an ordinary Bunsen furnace with Is burners in
which was porcelain combustion tube fve-
eighths of an inch internal diameter. and IS
inches long. Inside this tube. about three
inches from the end toward the absorption ap-
paratus, was granulared and porous oxide of
copper, occupying about four inches of the
length OF the tube and filling the bore. This
was held in place by asbestos plugs at either
end Next TO the oxide of copper, toward the
boat, was placed roll of metallic silver
about inches long, nearly filling the bore of
The tube. Rubber corks were used at each
end. The combustions were all made in oxygen
gas, using air to finish the aspiration ana clean
out the tube. The oxygen gas used was OBJ
tanned in the market In cylinders, the gas being
compressed to $50 pounds per square inch. Be-
tween the oxygen holder and the combustion
tuuc Wdo PiaOSu uioI u copper LuUe, aDOuL 4
feet long and n inch in diameter, fitted with
three coils at the middle; next a potash bulb,
and after that chloride of calcium tube.
HOW THE OXYGEN GAS WAS USED.
All the oxygen gas and the air used in the
combustions, was passed through these parts.
The copper coils were kept red hot by Bunsen
burner during the passage of the gases, the idea
being to burn any possible traces of combusti-
BILE in the gas or air before they should go into
the combustion tube. Between the absorption
end Of the combustion tube and the potash
bulbs we're, first washing tube containing
about c. of sulphate of silver solution, with
perhaps a gram of silver sulphate and next,
a chloride of calcium tube.
The potash bulbs were of the Geissler order
of small size made to order These were fit-
ted with small chloride OF calcium tube con-
tanning chloride of calcium simply, and COM
monty called the prolong The whole absorp-
ton apparatus weighed, when charged, about
go grams The absorbing solution in the bulbs
was the ordinary caustic potash solution rec
ommended by Fresenius. The absorption ap-
paratus was protected against the aspirator
bottle Dy full size chloride of calcium tube
The joints were made with ordinary rubber
tubing. The carbon from the steel was caught
on an asbestos filter in a platinum boat and
dried after very complete washing. The boat
with its filter and carbon was put into the
tubes without transfer. During combus-
tions o slight pressure above the atmo-
sphere was always maintained in the
oof;nued a.. T,oS,fb Dur, N