The Opelousas courier., 1885-07-11
WONDERS OF COAL TAR.
One of the Marvellous Results
Due to Chemistry.
Gorgeous Dyes and Useful Products
Obtained from a Refuse

Chemistry is capable of wonderful
things" said an expert in chemical sci
ence, shut in nothing to which it:
principles were ever applied have suct
marvellous results followed as are wit
messed in its manipulation Of common
gas or coal tar. Thirty years ago thu
problem of how they were to rid them.
selves of this foul and then utterly use.
less refuse of the retorts was puzzling
manufacturers of gas, and the aid OF
chemistry was sought in working out
the solution. They had N thought
beyond the utter humiliation of the
offensive tar. In their experiments
with the refuse the chemists discover
ed the so-ealled burning naphtha,
which, however, could be applied with
safety to no practical purpose. After
the naphthas a.@s extracted H. AZ d. va w.
left in the form of a heavy oil, which
vas still more of a nuisance than the
original compound, as it was more diff
cult to store and handle. The chemist
Belief discovered a channel of utility
for this oil in applying it as a pickle
for the preservation of railroad ties
bridge timbers, and similarly exposed
woods. This used up large quantities
Of the refuse, but only partially reliev-
ed the tar nuisance.
THE only hope that gas men now
had was that some discovery might be
made in chemical experimenting which
would give a commercial value to the
refuse. Faraday next awoke interest
in coal tar by his discovery of benzine
as a product of the tar oil. 1t was in
experimenting with the volatile sub
stances of these oils that the great
chemist Mansfield lost his life by an
explosion in his laboratory, and it was
probably this casualty that directed
greater attention to the possibilities of
the despised gas tar.
"It was not until 1857, however, that
the great value Of coal tar as a raw
material was demonstrated. In that
year Perkins discovered its aniline
properties, "a discovery which has al.
most revolutionized the trade in dye
stuffs. Perkins took coal tar naptha,
and, boiling it in a retort, obtained a
chemical action which resulted in ben
zole and nitro-benzole. Adding water
to this, the nitro-benzole was deposit
ed in the form of a thick, oily mass.
This he experimental with in various
ways, and finally, by the addition Of
acetic acid and iron filings. he pro-
duced a colorless fluid which is aniline.
This liquid he treated with different
chemical salts, and the result was green
crystals of q metallic lustre. These he
found yer capable Of producing, un-
der different chemical reactions, the
most brilliant and gorgeous dyes-the
aniline hues OF the paint a1d dye
trades of to-day.
aThis discovery made the long-de-
tested coal tar a desirable product of
the gas r%etorts, but it held still great
er surprises. From the light oil of the
tar valuable naphtha solvent for In
dia-rubber was obtained, and then the
discovery of carbolic acid
was made. How many people in ordina-
ry life know that this great disinfect-
ant Is n of the products of common
gas tar2 After these properties were
from the tar there were left
heavy oils and residuum, for which
was puzzled to ind q prac-
tical use. It was not until 1869 that
any satisfactory result was obtained
BY experimenting with this refuse,
and then the great discovery of aliza-
rine was made. This product was first
obtained by the German chemists
and Liebermann, but Prof.
Perkins, who had developed the ami
line colors from tar, was the first to
give q practical application TO the Ger
man work. The Importance of this
discovery may be understood when it
known that in the first ten years
following the introduction of the arti-
fetal alizarine In The dyestuff trade, it
exceeded the total amount OF natural
alizarine, or madden root, that had
been handled in the trade previous to
it's introduction. IL was, If anything,
superior 20 madden, and SO much
cheaper that the savings by its use up
10 1880 had amounted to over $4,000,
BOO. The discovery Of alizarine in
coal tar converted 100000 acres OF
land that had been used for growing
madden root into fertile fields of corn
and other cereals. With vegetable
madden It required nine weeks to per-
fect the dying Of q material Turkey
red. The artificial madden accomplish
I'd the desired result In as many hours. |
Three years ago the chemist produced
IN artificial indigo from the residuum
IL gas tar. and, In connection with the
anilsro dran nrd aIfra rive re tie rns,,c