, 1875-01-31
THE SMOKE QUESTION.
Consideration Of the Theory Of CON-
bUstion,


| To the Edi,or ef The CAis11o Tribune:
CHICAGO Jun. 28.-Having noticed with grati-
| fcation your interest in the abolition OF tho
smoke nuisance. which prompted you to publish
| series Of articles, will venture to furnish, in
| addition, or supplementary to these articles the
Information have on tho subject Of combus-
! tion, and excuse the venture by the fact that,
in former stages Of life had opportunity and
| occasion to investigate the subject somewhat.
| Besides the theory Of combustion furnished By
your reporter, to say the least OF it, is rather
| liable to leave people wanting information on
! the subject pretty much where thsy were be-
| fore.
COMBUSTION.
| The recognized interchangeable forces Of na-
ture are heat, light electricity. chemical affinity.
! What re call phenomena arc but the interchange
| OF these forces, which must be regarded as mere
| forms OF one common enorgy. When ncat in
crease8 beyond certain boundary, light will
make its appearance the heat beyond this bound
aty partly assuming the form Of light. When
electricity sets in it Is at the expense OF the
othor forms. So does the destruction of affinity
yield heat, light, or electricity. Related ele-
lneuts will combine. In the act 0! combination
the affinity is destroyed, md heat appears in all
cases. II there is much affinity aud the process
Of combination ia lively, ther light will appear
/ with the heat. Whenever this ia the case We
have to deal With combustion, which ia the COM
bination OF elements under development Of heat
aud light. It is not necessary in all cases tha.
one Of these elements must be oxygen, though
COMMONLY this is the case- Combustion may
take place with hydrogen aud other clements
chlorine, for instance, combining with hydrogen
under development Of heat and light. Com
bustion which ia instantaneous is called ex-
plcsion.
The principal elements Of fuel ara carbon and
hydrogen mixed with more or less earthly aud
other foreign substances which are left behind
az ashes. The hardest anthracite coal contains
tho least the eoftest bitumnous coal the largest,
) amount of hydrogen. Petroleum ia d cazbo-
hydrogen, from thick crude oil down to the
lightest gasoline, only varying in the proper
tious. Resin and turpentine are carbo-hydrogen.
Fat oil, wood fibre, alcohol, are carbo-hydrogens
with proportion OF oxygen. Both carbon and
hydrogen form lively combinations with oxygen
under Development Of heat and light. the prod
Ects being in the one case carbonlc acid, in tho
other water-vapor, though carbon, imperfect
" combined, may yield but carbonic oxide.
In the case OF any fuel already continuing
oxygen, there is large surplus OF the other
elements calling more oxygen into requis1-
ton. To initiate tho oa1nDinating OF tho e:e-
,ments With oxygen SO largely diluted rs it oo-
ours in the atmosphere, requires in au ordinary
cases high degree OF temperature. The process,
set once agoing, wa all know, generally CRATES
more heat than is required tor LII maintenance
FLAME.
Flame accompanies tho combustion OF gases
only. Purely carbon merely becomes vhito
with heat. TIE blue tiaae We observe with coke
aud hard coal il either that q hydrogen gas,
which, slightly charged with caSbon, is separas-
cd from tie coal. or that OF ca-bon1c oxide gas
first arising out OF imperfect combustion and
then itself burning when in contac: with more
oxygen. Tha flame Of pure hydrogen gas IL Or
dinarilv next TO uon~lum1nous, and that OF alco-
hol and carbonio oxide but little better. As tho
hydrogen becomes more aud moro charged With
carbon tho flame increases IN lumlnoeity. and
an ovorcharge with carbon produces smoke:
fine particles Of tho carbon are carried OF with
the products Of combustion These particles
are, however, not directly derived from the coal
crude coal is not carried off-they are O pre-
cipitate from carbo-hydroeen gas first developed
from the coal or oil, which occurs within the red
central portion Of tho damo while The out
or rim appears blush and and the Inner Inner
precpitated particles Of carbon being balieTed to
explain the luminosity OF tho fame. To render
tho flame of hydrogen gas luminous, it Is but
necessary to introduce into its centre rcs,stlng
earthly substance, which becomes te-heated.
and throws OF some OF its molecules. Such is
the theory Of the lime Incorrectly called calcium)
and zircon lights.
I will now mention remarkable TACT. con-
nected with tho degree OF pressure Of tae atIno-
sphere in which combustion takes place,-a fact
Of the utmost Importance as to the question OF
perfect combustion, and with which every eogi-
neer should be familiar. dull smosv flame
grows brighter as the air becomes raritlod 30 Us
lastly to becomo almost non luminous. Ike
the flame Of alcohol. a non-lum1n-
as the air is condensed so as to become lastly
smoky and quito thick. Thus even the flame OF
pure hydrogen becomes luminous under high
degree of pressure, which fact would seem to
upset the theory Of luminosity first given. were
it not, az believe, Tor the other fact that COM
mon air contains. as is we'll established, quite an
amount Of matter furnishing carbon and earthy
particles to the fame. We oil know that the
gas developed from the wick OF kerosene lamp
burns with q very smoky fame. Combustion be~
comes at once perfect as ue put over the flame
chimney which keeps heated ii. c.: rarifed air
around it. We likewise know that another mode
(though VIC are less successful here) OF produc-
ing luminous famo from tho oil is to f1rst OK
rand the gas before allowing it the full contact
With the air.
In this connection will at once mention .
case in which instantly solved the problem OF
perfect combustion in this very manner. For
heating By means Of heavy OIL had con-
a.ed with twonty gas-pipes and allowing II
inch space all around for tho purpose OF cou-
Quoting tho air around and into the body OF the
gas. The result was very dull, smoky flame,
and the beat was very unsatisfactory. Hay1ng
3 space Of about 20 inches below the pan, at
once introduced there q basin filed with glowing
charcoal. At this instant combustion becaas |
perfect, the fame wa3 perfectly ffee from
smoke, and even consumed the SCOT first de- |
posted On the walls OF the furnace and pipe |
The heat, OF course, wes very satisfactory
ORDINARY COMBUSTION.
Wle1, hard coal il thrown into furnace there
is developed light hydro-carbon, gas, which |
nav escape wholly or partly uncombined; and |
if tLe supply Of oxygen is scanty, the con'b;na-
ton will stop at its first stage under develop |
ment of but hall tho amount Of heat Carbonio |
oxide will be formed, which 1uag;escapo with the !
other gas. Here then, ere chances for consd-
erabie iossen though particles Of carbon itself |
do nos escape. When soft coal is thrown in, tho |
Developments Of heavy hydro-carbon gas is very |!
rapid. Not only will this gas Or considerable |
portion Of it, oscace uncombined, but Thlio !1e
gives tho smoke its tint. Ordinary smoke con-
sists therefore, Of five distinct elements first
+ha 1,ro,ar nr.ndnetq Of combustion. which are |