Elmore bulletin. [volume] (Rocky Bar, Idaho) 1889-1906, 1889-11-23
USES OF COAL TAR,
brilliant coiors Extracted Prom . san
stance Oaee Considered Worthless.
The cnnl tnr created hr fraa making

brilliant Coiors Extracted Prom q san
stance Oaee Considered worthless.
The coal tar created BY gas making
vas for many years burned. together
with the coke. under the retorts of
the gasworks. in order TO economics
coal; and not until Holman. distin-
guished German chemist. investigated
coal tar ientifically was IL found to
contain bodies that have since become
the basis OF the worlds great color In
iustries. The brilliant nnilinc colors
now used for dyeinv are all extracted
from coal. Coil tar yields. ON redls-
iil.ation, among other things "a large
amount OF volatile oil called benzole.
Holman found that benzole. upon
proper treatment with certain chem
icals. yielded aniline This il an oily
liquid. akin In its nature to the liquid
slkaloids. nicotine from tobacco and
,onine from hemlock. Hoimann also
succeeded in getting beautiful deep
magenta dye from aniiine by oxida-
tion. process In which substance
called the oxidizer gives up some Of
It's oxygen To the body oxidized. This
dye he called rosanlline. and from IL
may be obtained every conceivable
shade OF color. Ii IL curious fact
this intense dye Is co.orless in an alb
solutely pure state, but on uniting
with acids II at once takes on its char
acteristic vivid crimson color Since
the most important part In the manu-
facture of these dyes depends upon
the oxidation OF the aniline. II is neces-
sary To get some common aud neg
| pensive substance for that process.
Unfortunately for the personal COM
Tort of many people. arsenic acid. one
Of our most fatal poisons. is the sub
stance generally used. ]; is due to
this chemical that so many OF the fab
rics dyed with aniline coiors are in
furious The dyes in themselves are
harmless. The arsenic acid Is not es-
seutial to the color. but after II has
done its duty as an oxidixer, the man
ufacturer does not take the trouble to
remove the poison carefully from the
dyes The suggest on TO use other
oxidizers that are harmless has often
been made, but arsenic acid IL In such
general use that manufacturers are
unwilling 10 give IL up.
II Is said Of Hoimann's discovery
that IL was the result OF chance. He
had been trying the action of aniline
with different chemicals. and without
cleaning his test tubes had left them
standing in the rack. The next day,
npon his return 10 the laboratory. he
found. TO his Joy and astonishment.
that something quite unexpec ed had
taken place Beautiful crystals of q
deep magenta color had formed during
the night in one OF the test tubes.
With eagerness he examined them.
but could not remember how they had
been formed. At last II occurred 10
him that this was the result OF the OK
idation OF aniline. This was the be-
ginning OF Hoimann's great work upon
rosaniline.
IL has al.o been discovered that
another body contained in coal tar can
be converted into one of the most Inn
portant and beautiful vegetable dyes
known = the dycing matter of the
madder plant (alizarineD. and since
the discovery the prices OF madder
are so low that II Is unremunerative "a
raise IL. and the cultivation Of the
plant may be considered as thing ol
Che past Such IL the wonderful
growth OF the discovery. II IL the
fruit of scientific researches in organic
chemistry. conducted mostly from a
scientific point OF view.
One very important coloring matter
related to coal tar. and one OF the
original sources Of aniline--a product
OF rs great value as alizarine vel
TO be produced on large scale. This
Is indigo Adolph Baeyer. German
chemist. has shown that 1t can be pro
dnced artifcially. but at present No
practical means of accomplishing Il
have been discovered. No doubt how
ever, II will not be long before this Ia
achieved. and the cultivation of the
indigo plant will share the fate OF the
madder. Boston Herald.