Pittsburg dispatch. [volume] (Pittsburg [Pa.]) 1880-1923, 1892-11-16

isfactorily used by him for three winters in
London and one winter afterward in
America. 1t had a downward draft through
the CRATE and was practically smokeless.
a fire in it without filling the room with
| smoke. This difficulty led Franklin to de-
sign another stove which, although not SO
smokeess as the preceding, was more pfac-
| tical and may contain the germ Of future
| smokeless stoves and fireplaces. 1t con-
| sisted essentially of q cylindrical CRATE sus-
pended in fireplace and movable about on
horizontal and vertical axes
How Franklin Worked His Stove.
Franklin thus describes its use: "In max.
ing the first fire in a morning with this
grate there is nothing particular to be OBJ
served. 1t Is made as in other CRATES, the
Goals being put in above, after taking out
the upper bar and replacing it when they
are in. The round figure OF the fire when
| thoroughly kindled Is agi eeable; it repre-
sents the great giyer OF warmth to our sys-
tenn As it burns down and leaves vacancy
above, which you would fill with fresh Goals,
the upper bar is to be taken out and after
| ward replaced. The fresh Goals, while the
| CRATE continues in the same position, Will
| throw up as usual a body of thick smoke.
/, But everyone accustomed to coal fires
in common CRATES must have observed
that pieces of fresh coal stuck in below
among the red Goals have their smoke so
heated as that it becomes flame as fast as 1t
is produced, which flame rises among the
Goals and enlivens the appearance OF the
fire, Hero then Is the use OF this swivel
CRATE. By a push with your tongs or poker
you turn it over on its axis gently till it
again faces the room, whereby all the fresh
coaIs will be found under the live Goals, and
the greater part OF the smoke arising from
fresh Goals will in its passage through the
live ones be heated so as to be converted
into into, flame; whence you have muen more ore
longer preserved from consumption.
Since Franklin's time our manufactures
and population have grown enormously,
and with them the use of coal and the pro-
ductlon o. smoke. Yet until recently no
successful efforts appear to have been
made, on large scale, to abate the produc-
tion of smoke with its attendant evils. Chi
cago and Cincinnati have passed ordinances
forbiGding the emission OF black smoke ex-
cepT from dwellings. st. Louis is seriously
considering the question, but has as yet
taken no legal steps.
Due to the Efforts of Women.
The present agitation of the smoke ques-
tion in Pittsburg is due to the Women's
Health Protective Association of Allegheny
county in the hope of that the benefits of u
comparatively unpolluted atmosphere en-
joyed during the use natural gas may not
be lost as that valuable gift OF nature
disappears.
Ali commercial fuels contain the elements
carbon and hydrogen as essential constitu-
ents, and in addition others, chiefly min
eral, which enter only indirectly into the
process of combustion, usually with the re-
suit of retarding it. They form the ash of
the fuel, and hence are Questionable but
unavoidable portions OF it.
Carbon is solid. When it burns it be-
comes incandescent and glows after the
familiar manner OF a charcoal or a coke fire,
and when the combustion is rapid and COM
plete it does not yield any visible flame.
Hydrogen is a gas. 1t burns always with
incandescence is so SO slight that i'll bright
daylight it is very difficult to see the flame
which, indeed, emits only a faint blush
light in a darkened room.
1t follows from the above statements that
the hydrogen is the flame producing in
gredient of fuels, while carbon is the incan-
purposes, fuels may be divided into those
which burn with very little flame or smoke,
and those which burn chiefly with flame
and which may emit mucn smoke. The
smokeless fuels are charcoal, coke and an
thracite coal; these contain very little hy-
drogen and usually upward OF so per cent
OF their weight is carbon. The flaming fuels
are wood. bituminous coal, petroleum,
pitch, natural gas, and all forms of oils and
fats, whether derived from fishes, animals,
or vegetables. In these the hydrogen may
range from to 25 per cent.
An Explanation of Combustion.
Combustion is process of oxidation, and
consists in chemical union between the
carbon and hydrogen of the fuel with the
oxygen of the air. Hydrogen and oxygen
proportions, forming two oxides called re-
spectively carbon mono1ide and carbon
dioxide. This latter is often called carbonic
acid, and represents the final result OF the
complete combustion of carbon. These pro-
ducts are fixed gases, and, since ut the
temperature of the flame, water can only
exist as steam, We may consider all the pro-
ducts OF the complete combustion OF a uel
as being invisible gases, which escape into |
the atmosphere. A jet of illuminating gas |
burning IN an apartment very nearly |
realizes this condition. But the hydrogen |
and carbon of a fuel are not simply mixed |
together; they are combined, forming q class
of compounds known as hydrocarbons of |
which natural gas and petroleum are |
familiar examples.
Now, hydrogen ignites at q lower temper
ature than carbon. Moreover, being gas it
mixes readily with the air, and hence is
more combustible than carbon. When q
hydro-carbon is heated to a temperature
considerably above red heat it begins to
separate into gaseous hydrogen and solid
carbon, the chemical oxidation which con-
situtes combustion cannot take place until
this preliminary separation begins. Now it
will lie seen that If the supply of air is |
ample, both the hydrogen ana carbon will
burn completely into curbon dioxide and |
water, and only odorless and invisible
products of combustion will result; but if |
the air supply is not ample or, what amounts |
to the same thing, il the air is not nearly in |
mixed with the vapor OF the !
then the hydrogen being |
more combustible than the carbon will |
tOk0 most OF Tile oxygen present anu leaVc
the carbon in the form OF small particles, |
which. while hot, radiate light, but which |
soon float outside the borders OF the flame, |
cool down and appear as SCOT and smoke. |
The Cause of Black Smoke.
Improper supply of air is then the sole |
cause OF the production of black smoke. !
But there is another kind, O light yellow
smoke which is produced from another
cause. If oil or fat is dropped on the top of
4 stove which is barely red-hot, much light |
white smoke will result, but there will be |
no flame and no combustion; this is because
the oil is vapoIiZed, or in technical Ian
guage suffers destructive distiliaton. All |
the elements OF the Oil are still present and
If a lighted match is applied to the column
Of smoke it will ignite and burn with
bright flame. Similarly, when bituminous
coal is charged on the top of a fire it cannot
all be heated instantaneously, but portions
of it will suffer destructive distilation as it
approaches dead heat, and a
thick yellow smoke will be given off from
all parts OF the freshly added fuel where the
is not high enough to ignite 1t.
This yellow smoke consists mainly OF |
small glubules of oily ana tarry bodies,
which give to coal smoke its adhesive and
greasy character.
II we could always have a flame playing |
over all portions of the toD OF u nre and at
the same time an ample supply of hot air
thoroughly mixed with the Iuel gases, there
woulu never be any notable quantity of |
either yellow or black smoke passing up the
Theoretically the complete u aboli-
lion OF smoke can be secured by having a
AL l.rNf I