The Sun.
London, England, 1854-04-19 00:00:00

Then, if the area were reduced to half a, square inch, it
would require a velocity of 80 feet per second to pro-
vide for the admission, within the given time, of the
necessary quantity. By dose observation, by means,
of an aerometer, the velocity of the entering current
was estimated at from 8 to la' feet per second, if the
draught was good ; and from 5 to 8 feet when it was but
moderate. Again, it was observed that, by admitting
the air through numerous thin 'films or divisions, the
velocity was necessarily reduced by mere friction through
so many half-inch orifices as were exhibited in the models
and drawings on the table. The mode dadmitting the
air by numerous email orifices, as practised by Mr. C.
Wye Williams, was then oOnsidered, and it was shown
that the great object to be effected was, the division of
the air, on its admission to the furnace,' so that no more
atoms were brought into contact with the atoms of the
gas, at any one momonte than were required for their
successive union and combustion., If this were the case,
combustion and heat would be generated, continuously,
as the gas and air came into contact. If, however, the
air entered in a body, or even in a film, in larger quan-
tities than could be taken up by the gas, before the tem-
perature was lowered, a refrigeratory effect must be the
consequence, smoke would be formed and fuel would be
wasted. It . was asserted that the_ phrase " burning
smoke was improper, inasmuch as the smoke did not
exist until the gases had left the furnace ; this was de-
monstrated by a diagram, showing that on distilling
coal in a close vessel, and forcing in a small quantity of
air, a jet of gas issued, which, on ignition at the ori-
fice, was almost colourless, then merged into flame, and
ultimately became opaque smoke. It was stated, as an
argument for the necessity for some stringent measure'
with respect to the engine furnaces in all large, towns,
that in the last nine years, between 1845 and 1853, 801
new chimney shafts had been erected in the metropolis
for manmfactories, breweries, &c.. Some few of them
might have been merely re-built, after destruetion, but
the large majority caused additional impurity in the
London atmosphere. From 1845 to 1851 the greatest
number built in one year was 99 ; but in 1852 111 were
constructed, and in. 1553 the number rose to 123. It
was contended that, in dealing with the smoke ques-
tion, too much stress had been laid on the chemical part
of the subject, as also, that the statement of its being
" impossible to burn smoke" had complicated that
which was, in itself, a simple question. All that the
public cared about Was, that by some simple means the
black or brown visible smoke should be prevented from
forming, or be consumed, if its formation was inciden-
tal to perfect combustion. The air necessary to per-
form this could be admitted anywhere, either through
a split bridge, by the fire-door, by an infinite num-
ber of holes, between plates, with narrow spaces, or by
others arranged like Venetian blinds. Practically, the
end could be attained
hy the mechanical systems of
Juckes, Hazeldine, Hall, and others, or by the double
furnace boilers of Galloway, Rose,, M‘Gavin, and others,
or by the systenes of Williams, Prideaux, and many
others. The objections alleged against all these plans
were illustrated, and it was stated that, with ordinary
boilers, the admission of air invariably reduced the eva-
porative power, or caused waste of fuel, unless there was
a sharp draught, and spare boiler power ;. but that when
these latter requisites were, secured the air
.might, be ad-
mitted in any way practically found most convenient.
The arrangement proposed by Mr. Prideaux was noticed
as the most creditable teeeleanicism yet brought forward,
but its neatness was its .onry recommendation, as it could
not improve the draught, nor could it aid in " burning
smoke" better than would be chine by merely leaving the
furnace door ajar. The remarkable coincidence between
the arrangement of the parallel plates in Prideaux's fire
door and that of William's well-knewn and long-prac-
tised system was also noticed ; it being stated, as funda-
mental principles, that in the former system " the door of
the furnace should be double, and the air should pass
into the furnace through a series of perforations in the
inner plate. By this arrangement three important re•
sults are secured-1. The heating of the air. 2. Its
subdivision into minute jets. This is the precise prin-
, cipie and operation of Mr. Williams's argand furnace.
3. The keeping of the outer surface of the furnace-deer
comparatively cool, and thereby both economising heat
and preventing its radiation outwardly, to the annoy-
ance of the attendants." Drawings were exhibited e
double flue and double furnaoe-boiler, whose action was
stated to be very. satisfactory ; the proportion of air
space provided, in that case, was one square inch to each
square foot of grate area. The admission of too large
quantities of cold air immediately behind the bridge had
been found prejudicial, and the system of admitting the
supply of air through the perforations in the fire doer was
generally preferred, The system of alternate firing, and
of having ample boiler space and a good draught, was in-
sisted upon. It was stated, on behalf of the mechanical
methods of firing, that at Price's candle manufactory, at
Vauxhallo three methods, Hazeldine's, Jucke's, and
Hall's were employed with success. The general prin-
,,ciple of a continuous supply of fuel, at the front of the
fire, by means of moving bars, carrying the coal for-
ward, was common to all these apparatus. The air was
admitted only from below, and between the bars, which
were always covered with fuel. The objections urged
against these machines were, the first cost, and their
liability to derangement. These, however, were now di-
ThiOiehed, particularly with those of. Juckes and Hazel-
dine, to which preference.was therefore given in the con-
strUction of new furnaces. They were found to pro-
duce almost perfect combustion, and to make a great
saving of fuel, with other prattical advantages. Two
cases were mentioned, as' illustrative of the necessity
Of,adruitting the air above the, incandescent fuel—the
first was that of the ventilating furnaces in pits where
'it was essential to raise, to a certain temperature, the
'largest amount of air by passing it .throngh or over
the fuel in a furnace, in such a manner as to render the
air as, light as possible, and not-to encumber it with
smoke ; the second was that of coke Ovens, which were
now constructed in' pairs, and were worked alternately,
in -such a manner that the early smoke from one oven
mingled with the later development of gases from the
other oven ; by this means the appearance of any opaque
smoke was entirely prevented. In reply to the argu-
ments in, the papers, and to some of those used by the
speakers, it was urged, that even with the best con-
struction,of fur/lame, skilful firemen must be employed,
and that it was desirable the subject should'be divested
...of 41, complexity, and should he :rendered" clear to
the meanest capacities. - Instances were given of
the advantageous employment of mechanical methods
lortriitttnoki:ig Ha, particularly ato:,the
whebrree veseiterxyeenf._
`betsrosf.
Juckes's apparatus had been used for several years,
and , had induced a great saving of fuel, as well as
insured undeviating regielarity of temperature in
the furnaces. The self-acting systems practised by
Brunton and by ParkeS, many years since, were al
luded to, and the reasons for their usebeing discontinued
were given. The alleged defects of these systems were
shown not to exist in theappareteis of Juckes, Hazel-
dine, and Hall, but that even they were up to this time
Unfit' for use in steam-vessels, where, ,it had been
imagined, that mechanical means of firing would have
been most advantageous, but where, in reality, the heat
in the furnaces was so intense as to destroy any ma-
chinery attached to .the fire-bars. The success attend-
ant on, Mr. Houldsworth's system for preventing smoke,
and on his invention of the metal rod pyrometer, was
described. = The general result of the 'investigation ap-
peared to be, that, although for certain' large establish-
ments, the mechanical methods of 'firing- were success-,
ful, it could not be .expected they would be *opted for
every furnace in the smallest manufactory; therefore, a
good system of mingling a due proportion of atmos-
Therio air: With-the gases- --evOlvett- dunng '-combustion
Avas-Vlssatiat: =dila itroloyad by lllieimr
-
appeared to fulfil the required eouditioae.