Evening capital. (Annapolis, Md.) 1884-1910, 1885-05-19
WONDERS OF COAL TAR.
one or the Marvellous Results
Due to Chemistry.
Gorgeous Dyes and Useful Products
Obtained from : Rsfusa

Chemistry is capable Of wonderful
things" said an expert 10 chemical sci
ence. shut in nothing TO which its
principles were ever applied have such
marvellous results followed as are wit
messed in It's manipulation of common
gas or coal tar. Thirty years ago the
problem Of how they were to rid them
selves Of this foul and then utterly use
less refuse of the retorts was puzzIing
manufacturers Of gas. and the aid of
chemistry was sought in working out
the solution. They had no thought
beyond the utter annihilation of the
offensive tar. In their experiments
with the refuse the chemists discover
ed the so-calIed burning naphtha.
which. however. could be applied with
safety TO no practical purpose. After
the naphtha was extracted the tar was
left in the form Of a heavy oil, which
was still more Of q nuisance than the
original compound, as IL was more diff
cult to store and handle. The chemist
Belief discovered a channel of utility
for this oil in applyingit as pickle
for the preservation of railroad ties.
bridge timbers, and similarly exposed
woods. This used up large quantities
Of the refuse. but only partially reliey-
i al The tar ,ufaonoa
"Tha only hope that gas men now
had was that some discovery might be
made in chemical experimenting which
would give commercial value to the
refuse. Faraday next awoke interest
in coal tar by his discovery Of benzine
as 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.
ut was not until 1867, however, that
the great value of coal tar as raw
material was demonstrated. In that
year Perkins discovered its aniIine
properties, discovery which has al
most revolutionized the trade in dye
stuffs. Perkins took coal tar naptha,
AID, boiling it in retort. obtained a
chemical action which resulted in ben
1ole and nitro benzole. Adding water
to this, the nitro-b enzole was deposit
Cd in the form OF thick. oily mass.
This he experimental with in various
ways, and finally. By the addition Of
acetic acid and iron filings. he pro-
auced q colorless fluid which is aniline
This liquid ne treated with different
chemical salts, and the result was green
crystals Of metallic lustre. These he
found were capable Of producing. IN
der different chemical reactions, the
most brilliant and gorgeous dyes the
aniline hues OF the paint and dye
trades Of to-day.
"This discovery made the long-de-
tested coal Tar desirable product Of
lihe gas retorts. but It held still great
or surprises. From the light oil Of the
tar valuable naphtha solvent for In
Iaia-rubber was obtained, and then the
Invaluable discovery of carbolic acid
was made. How many people in ordina-
Try life know that this great disinfect-
mt is one of the products Of common
gas tar After these properties were
extracted from the tar there were left
heavy oils and residuum. for which
chemistry was puzzled to tind prac-
teal use. It was not until 1869 that
any satisfactory result was obtained
lby experimenting with this refuse.
and then the great discovery of aliza-
line was made. This product was FIRST
obtained by the German chemists
lGrabe and Liebermann, but Prof.
Perkins, who had developed the ami
line colors from tar. was the first to
give practical application to the Ger
imam work The importance OF this
discovery may be understood when it
| Is known that in the first ten years
following the introduction Of the arti-
acial alizarine in the dyestuff trade, it
exceeded the total amount of natural
Alizarlne. or madden root. that had
been handled in the trade previous to
It's introduction. It was. II anything.
superior 90 madder. and 50 much
cheaper that the savings BY its use up
to 1880 had amounted to over ST. 600.
200. The discovery Of alizarine in
Ieoal tar converted 100000 acres OF