Semi-weekly south Kentuckian. [volume] (Hopkinsville, Ky.) 1883-1889, 1888-03-16
ILLUMINATING GAS.
How 1t Is Manufactured and the Prouucts
Created by Its Distillntion.

sists of three distinct operations; ~
distillation, the driving of of tho gases
from tho coal by heat; (2) condcnsa-
ton, the separation of the water an
and other condonsablo vapoTs; (S)
publication, the removal of the sui
phur compounds aud carbonic acid.
II the bowl Of mn ordinary clay pipe
is filled with small pieces of bltumin-
GUS coal, covered over with clay, and
placed in bright fire, smoke will Mt
once begin to issue from tho stem
The smoke soon ceases. when, ii n
light is applied to the hole in the STEM
the gas then issuing will burn with a
bright steady flame, while thin
black tarry substance oozes out OF the
hole. This is on n small scale the dis
tillation part Of the gas-making proc
ess
In the manufact ure of gas on COM
mercial scale, coal is placed in long,
horizontal { shaped retorts, made
sometimes of iron, but usually Of fire
clay, set in groups or benches OF three,
five. six or more, and heated from The
outside by fire, usually of coke. The
coal being charged, say from l6O 10
POO pounds, the mouth of the retort is
closed with a lid held in Place by n
screw, the joints being made sight by
luting with clay. As tho retorts are
usually red hot from previous charges
the gas begins at once TO pass over
from tho coal to the con icnsing ap-
paratus In about four hours the re-
tort is opened. the coke drawn and
ouenchcd with water, while q now
charge of coal is Introduced, and thus
the proc ,ss Is n continuous ono The
character of the products OF distillation
varies greatly with the coal charged
and the heat applied. Too low heat
gives q large proportion OF con-
densable vapors, which are lost in the
tar; TOO high heat injuries the quail
ity of the gas by dccomposing it into
non-luminous marsh gas and hydro
gen.
The products of distillation are,
roughly speaking, four: gas, ammo
niacal liquor, tar and coke. The yield
of ton of coal varies greatly. The
products of Pittsburgh coal may be
taken Mt 10. 500 cubic feet of gas, l, $50
pounds of coke. 20 gallons of ammo
niacal liquor and 14O pounds of tar.
The gas goes TO the condenser and
purifier to be prepared for distribution
to consumers. A part Of the Tbs e efforts is
one- Ali TEST t is sold. The ammoniacal
liquor is made INTO sulphate of am
most valuable manure, 10S
gallons of liquor making one ton OF
sulphate, while the tar is used TO make
an almost endless variety of sub
stances, the most brilliant and varied
colors. anilines, the most delicate per-
fumes, the most useful medicines, and
the sweetest product saccharine,
known to man. A list even Of the
products derived from this black. ugly
looking tar would fill this column.
There is no fairy tale than in wonder
or interest surpass3s the story Sir
Henry Roscoe tells of coal tar From
the tar of ton Of coal are obtained
ZIG pounds pitch, II % creosote, Is. A
heavy oils. s 90 yellow naphtha, 6.72
naphthalinc, L. As naphthol, 3 "a aliza-
rine, 224 soluble naphtha. 1.57 phenol,
l12 autrine, 0.7si toluidine, O Az an
thracine, and O. 500 toluene. From the
toluene, saccharine, more than two
hundred times swecIer than sugar is
made. These are again broken up
according to Roscoe. Already there
have been obtained sixteen distinct
yellow dyes. two orange, thirty red,
fifteen blue. seven green, besides a
number of browns and an infinite
number of blendings of all shades.
From coal tar comes n Product that
auiets fever, that serves as the basis OF
the perfume of ''new-mown hay" that
takes the place of the heliotrope flower
the vanilla bean. the bitter almond.
and stranger than all, that wonderful
" sweet saccharine.
L nO pIOCcSS We HuNc bOSh A7SSiip
ing is the coal gas process. A consid
cradle proportion of the gas consumed
however, is known rs waicr-gas. Thi
is in reality n mixture composed o
about two-thirds water-gas and one
third oil-gas, the form II produced b.
the action OF incandescent carbon Of
steam, and the latter by the distilla
ton of petroleum or its products
Water-gas contains no illumina ants, bu
has low specific gravity and a hig
heating power, while by almost an
method Of distilling oil, seventy cub
feet of seventy candle power gas en-
be produced from a gallon of oil. B
diluting this oil-gas with water-ga
an illuminating gas Of excellent quai
ty is obtained. u f. Weeks, in Cadt
tdaq~aa.