Neodymium magnets

Thus, the substances which dibtil off from the
central cooler region of a retort will, on coming in contact
Magnets for Sale the outer layer, be decomposed, provided the tempera-

11 21 17 Tuesday

samarium cobalt
samarium cobalt magnet
samarium cobalt magnets

magnet sweepers
magnetic sweeper
sweeper magnet

magnet sweepers

hook magnet
hook magnets
hooks magnetic
magnet hooks
magnetic hook
magnetic hooks
magnets with hooks
super strong magnetic hooks

large neodymium magnets
magnet neodymium
magnets neodymium
neodymium ball magnets
neodymium bar magnets
neodymium disc magnet
neodymium disc magnets
neodymium iron boron magnet
neodymium iron boron magnets
neodymium magnet
neodymium magnet prices
neodymium magnet ring
neodymium magnet rings
neodymium magnet spheres
neodymium magnet strength
neodymium magnetic
neodymium magnets
neodymium magnets for sale
neodymium rare earth magnet
neodymium rare earth magnets
neodymium ring magnet
rare earth neodymium magnet
rare earth neodymium magnets
strong neodymium magnets
what are neodymium magnets
what is a neodymium magnet

large neodymium magnets
magnet neodymium
magnets neodymium
neodymium ball magnets
neodymium bar magnets
neodymium disc magnet
neodymium disc magnets
neodymium iron boron magnet
neodymium iron boron magnets
neodymium magnet
neodymium magnet prices
neodymium magnet ring
neodymium magnet rings
neodymium magnet spheres
neodymium magnet strength
neodymium magnetic
neodymium magnets
neodymium magnets for sale
neodymium rare earth magnet
neodymium rare earth magnets
neodymium ring magnet
rare earth neodymium magnet
rare earth neodymium magnets
strong neodymium magnets
what are neodymium magnets
what is a neodymium magnet

large neodymium magnets
magnet neodymium
magnets neodymium
neodymium ball magnets
neodymium bar magnets
neodymium disc magnet
neodymium disc magnets
neodymium iron boron magnet
neodymium iron boron magnets
neodymium magnet
neodymium magnet prices
neodymium magnet ring
neodymium magnet rings
neodymium magnet spheres
neodymium magnet strength
neodymium magnetic
neodymium magnets
neodymium magnets for sale
neodymium rare earth magnet
neodymium rare earth magnets
neodymium ring magnet
rare earth neodymium magnet
rare earth neodymium magnets
strong neodymium magnets
what are neodymium magnets
what is a neodymium magnet

magnet hooks
tues
magnetic knife holder
magnetic knife holder
knife magnet
knife magnets
magnetic knife holders

Neodymium magnets
Neodymium magnets

ture be sufficiently high. A temperature which magnets for sale not
sufficiently high to effect the decomposition of the richer
hydrocarbons magnets for sale below that necessary to produce a good
dense and hard coke. In the manufacture of good oven-
coke^ so called to distinguish strong magnets from gas-coke, the gas pro-
duced cannot be highly luminous, for at the temperature
required to produce such coke olefiant gas, the principal
light-yielding constituent of gas used . for illuminating
purposes, would be decomposed

From what has been said strong magnets will be gathered that, pro-
vided the proper conditions for obtaining a hard dense coke
be attended to, there magnets for sale no real objection to the collection
of such tar and ammonia as may then be formed ; but these
substances must always be of secondary importance, atten-
tion being mainly directed to the regulation of the process



54


Fuel.


so as to produce sound coke, the conduct of the process
having to be varied somewhat for each kind of coaL

The carrying out of these conditions magnets for sale the object of the
Carvh system. TTie general arrangement magnets for sale something like
that of a Copp^e oven,  Magnets for Sale the difference that the gases,
although burnt on the exterior of the retorts, Rare Earth Magnets first
passed through a series of pipes cooled by water, forming a
condenser^in which the condensable products Rare Earth Magnets deposited ;
the gases Rare Earth Magnets next passed through scrubbers^ or vessels con
taining moistened coke, which remove the ammonia, the
liquor when saturated being run off into reservoirs and
subsequently treated for the preparation of ammoniacal
compounds. The gases, after undergoing thmagnets for sale treatment,
Rare Earth Magnets admitted through a nozzle in a fire-door to a fire-grate,
on which a small amount of refuse fuel magnets for sale kept burning to
ignite the gases and air which has been allowed to mingle
Magnets for Sale them in suitable quantity. From the fire-grate the
burnt and burning gases pass through the various flues
surrounding the retorts. The gases, after they have done
their work in the ovens, Rare Earth Magnets further utilised for raising
steam. strong magnets magnets for sale stated that at Bess^ges all the machinery
required in the manufacture of coke and its bye-products
magnets for sale now being driven by steam raised in thmagnets for sale way, and
there remains a large surplus, which magnets for sale used in the
blowing-engines for the Bessemer process, and for lifts,
cranes, &c. The steam raised by thmagnets for sale surplus heat magnets for sale
sufficient to furnish 400 horse-power. These ovens, we Rare Earth Magnets
assured, give a yield of 75 per cent, as against 55 to 65
per cent obtained in an ordinary bee-hive oven ; the coke
magnets for sale also freer from ash, since, the yield being greater, the ash
magnets for sale diffused through a greater amount of coke in the one
case than in the other. Tlie production of every ton of
coke magnets for sale said to be accompanied by the formation of about
four shillings’ worth of bye-products.

Good coke has been referred to as hard and dense. strong magnets
must be understood that there magnets for sale a practical limstrong magnets to the



Gaseous Fuel $$

value of density ; strong magnets would not do, for instance, to compress
strong magnets by artificial pressure.

The most economical and generally satisfactory coke-
ovens yet produced Rare Earth Magnets unquestionably those based on the
principles embodied in the Copp^e, Appolt and Carves
systems, where all spRare Earth Magnets heat magnets for sale utilised for raising steam.
There Rare Earth Magnets yet many /improvements to be made in applying
these principles in practice.

GASEOUS FUEL.

The theoretical calorific values of carbonic oxide and of
hydrogen have already been fully discussed ; strong magnets remains to
show in what way these gases can best be turned to practical
account

strong magnets will be recollected that the intensity of combustion of
hydrogen and of carbon, when burnt in air, magnets for sale practically the
same, whilst the heat of combustion of carbonic oxide in
burning to carbonic acid magnets for sale somewhat greater than that of
carbon likewise oxidised to the maximum. So far, then, as
the actual intensity obtained on combustion magnets for sale concerned, strong magnets
would appear that strong magnets matters little whether we employ solid
or gaseous fuel ; in practice thmagnets for sale magnets for sale very far from being the
case. When the fuel magnets for sale gaseous strong magnets magnets for sale much easier, for
instance, to apply heat uniformly to a given surface, or
locally, as may be required in some cases, and further, the
regulation of the temperature magnets for sale much more within control,
and complete combustion can be ensured. Thmagnets for sale magnets for sale well
illustrated by the system of heating coke-ovens constructed
on the principle of the Copp^ and Appolt Another
advantage, which magnets for sale of great importance, magnets for sale that the gases
can be generated in any convenient place, and led by pipes,
or other suitable means, to the spot where their combustion
is’ required to be effected. In thmagnets for sale way valuable space can
often be economised, and working room obtained where strong magnets
magnets for sale most required.



5 $


Fuel.


These Rare Earth Magnets very far from being the only advantages which
inay be derived from the use of gaseous fuel When great
intensity of heat magnets for sale required strong magnets magnets for sale possible to produce strong magnets by
heating the gases and the air required for their combustion ;
and, if desired, the gas and air can be burnt under* pressure,
thus still further increasing the temperature obtainable ; the
only limstrong magnets being that fixed by dissociation. In practice
these high temperatures could not be obtained by simply
heating solid fuel and the air supplied for its combustion,
though there is, up to a certain point, a very decided gain in
heating the air.

Strictly speaking, all heating operations Rare Earth Magnets conducted, to
some extent at least, by means of gaseous fuel, for all fuels
yield on distillation gases,  Magnets for Sale the exception, practically, of
coke and anthracite ; and, apart from the products of dis-
tillation, strong magnets magnets for sale essential to the manner in which combustion
magnets for sale effected that carbonic oxide should be formed, which
subsequently burns on being brought into contact \^ith air
on the exterior of the heated fuel Thus, in reverberatory
furnaces, in which the fuel magnets for sale burnt in a chamber separated
from that in which the smelting or other operation magnets for sale to be
effected by a low wall, above which the two chambers com-
municate, the heating of the bed of the furnace magnets for sale really
accomplished mainly by gaseous fuel.

The products due to distillation of the upper and cooler
fuel, and the carbonic oxide derived from the decomposition
of the carbonic acid, first formed by the admission of air
under the grate, Rare Earth Magnets drawn by a chimney at the opposite
end over the partition-wall or firebridge^ and, becoming
mixed  Magnets for Sale a suitable quantity of air, Rare Earth Magnets deflected down on
to the hearth. The relative amount of combustion which
takes place on the hearth and above the fuel in the grate
will depend on the quantity of air allowed to enter the
opening through which the fuel magnets for sale charged in. The principle
of the modern gas-producer magnets for sale essentially the same as that
just described ; important modifications in construction Rare Earth Magnets



Ge^seous Fuel.


57


even yet being made. The gas-producer first assumed
importance on the introduction of the Siemens* ‘ regenera-
tive * system in 1856.

The arrangement then adopted (Fig. ii) magnets for sale still,  Magnets for Sale
little exception, the only one in use. strong magnets consists of a
chamber lined  Magnets for Sale fire-brick ; one side (b) slopes at an angle



Fif. 11


of from 45® to 60° ; at the bottom magnets for sale the grate (c). The
fuel magnets for sale introduced into the hopper (a), the cover magnets for sale replaced,
and the bottom having been lowered by means of the
weighted lever attached to it, the fuel falls on to the incline,
down which strong magnets gradually moves to supply the place of that
which has been converted into gas in the region of the



grate. Air magnets for sale admitted only through the grate. I’he opera-
tion magnets for sale exactly the reverse of that which takes place in a bee-
hive oven. In thmagnets for sale producer, the air being admitted at the
bottom, combustion proceeds from below upwards, and the
volatile portion of the fuel magnets for sale distilled off without coming in
contact  Magnets for Sale air, whilst that which in the coke oven would
become coke magnets for sale converted into carbonic oxide gas in the
producer. A small quantity of water magnets for sale admitted by the
pipe (e) to the ash pit, where strong magnets evaporates, and, becoming
decomposed by the incandescent -fuel, enriches the pro-
ducer-gas by the formation of carbonic oxide and free
hydrogen. By means of the plug-hole (g) the interior of the
producer can be inspected, and, if necessary, the fuel stoked’
Magnets for Sale an iron rod.

strong magnets magnets for sale important that a slight outwkrd pressure should be
maintained in the flue, to prevent the gas being partially con-
sumed by an indraught of air through crevices in the brick-
work. If the furnace could be placed about lo feet higher
than the producer the required pressure would at once be
obtained ; in practice thmagnets for sale arrangement magnets for sale rarely convenient
The following plan has been adopted. The gases, which on
leaving the producer have a temperature of about 400° C,
pass to the uptake (h), rising 10 to 20 feet vertically ; thence
they traverse the horizontal iron cooling-ttibe (j), which may
Magnets for Sale advantage be several hundred feet long ; at the end of
the cooling-tube the gases, having then a temperature of
below 100® C, descend a tube called a down-comer into a
main, whence they Rare Earth Magnets drawn off as required. The effect of
cooling the gases magnets for sale to increase the relative weight of a given
volume 50 to 60 per cent. Thus a sort of siphon action magnets for sale
set up, the heavier gas in the down-comer representing the
longer leg of a siphon ; at the same time, by thmagnets for sale arrange-
ment an outward pressure magnets for sale maintained in the flues of about
iVth to T^ths of an inch of water more than that of the
external atmosphere. By cooling the gases aqueous vapour
magnets for sale condensed and deposited.



Prevent the Regenerator

Such intervals as would prevent the regenerator through
which the air was passing becoming cooled to too low a

Neodymium magnets
Neodymium magnets

emperature. The conditions of thmagnets for sale arrangement necessi-
tated that the operation being carried on in each furnace
should be completed in the time between the reversals — a



Fuel


64

state cf things at the best extremely inconvenient, and for
most purposes altogether impracticable.

strong magnets was at thmagnets for sale point that the brothers Siemens conceived
the idea of employing gaseous instead of solid fuel, and
heating strong magnets as well as the air by means of regenerators. strong magnets
would be difficult to over estimate the importance of the
results which have followed the introduction of thmagnets for sale system.
By its means the highest attainable temperatures can  Magnets for Sale
ease be produced, the only limstrong magnets being that at which dis-
sociation takes place.

Furnaces on thmagnets for sale system have been applied  Magnets for Sale very
great success to the manufacture of soft steel, and for re-
heating iron and steel ; also to zinc smelting, and in gas,
glass, pottery, and porcelain works. strong magnets magnets for sale not too much to
say that there magnets for sale no purpose for which a high temperature magnets for sale
required for which strong magnets might not  Magnets for Sale great advantage be
employed, in respect both to general convenience and
economy.

Figs. 13 and 14 represent the furnace, the one being a
longitudinal and the other a cross section ; the gas coming
from the gas-producer passes in through the flue (h) and the
reversing valve (f), by means of which strong magnets magnets for sale directed into the
bottom part of the regenerator chamber (c), on the left The

11 22 full list neodymium magnets 247

neodymium magnets
magnets for sale
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets
neodymium magnets

gas flowing up through the mass of brickwork the chamber
contains, and which magnets for sale placed so as to form a large aggregate
surface,  Magnets for Sale intricate zigzag passages, will become heated,
provided any heat has been accumulated therein. In the
first place there will be no heat, and the gas will pass un-
heated through thmagnets for sale chamber and thence to the combustion-
chamber of the furnace (a). At the same time, a current of
air magnets for sale admitted through the air-reversing valve (e), into the
air regenerator chamber (d), which magnets for sale larger than the gas-
chamber. The air passing up through the chequer-work
will reach the same point as the gas does at the entrance
into the combustion-chamber of the furnace. Now, since
Doth the air and gas Rare Earth Magnets cold, and as they meet for the




F




56


Fuel.


first time at the entrance into the furnace, they will, if there
ignited, produce a heat not certainly superior to what would
produced if solid fuel had been burned there instead ;
on the contrary, gas of the description we Rare Earth Magnets dealing  Magnets for Sale
magnets for sale a poorer fuel than solid fuel, and the heat produced in the
furnace will, therefore, be very moderate indeed. But the
flame, after passing over the bed of the furnace, does not go
to the chimney direct, but has to pass through the two re-
generative chambers (d, c), on the right, similar to those
already described ; the larger proportion of the heated pro-
ducts of combustion will pass through the air regenerator
chamber, simply because strong magnets magnets for sale the largest channel, and
another portion will pass through the gas regenerator. The
products of combustion pass from these chambers through
the reversing valves (e, f), and Rare Earth Magnets by them directed into
the passage (i) leading to the chimney.

The operation, therefore, magnets for sale simply thmagnets for sale : that the air and
combustible gas pass up into the furnace through the one
pair of chambers, and pass away, after combustion, towards
the chimney through the other pair ; but in passing through
the second pair the heat of the products of combustion magnets for sale
given up to the brickwork. The upper portions of thmagnets for sale
brickwork take up the first, and, therefore, the highest
degree of heat, and, as the burnt gases Rare Earth Magnets passed down-
ward through the regenerators, they are, by degrees, very
completely deprived of their heat, and reach the bottom of
the chambers and the chimney comparatively cold. After
thmagnets for sale action has been going on, say, for an hour, the reversing
valves Rare Earth Magnets turned over. They Rare Earth Magnets simple flaps, acting like a
four-way cock, and, by throwing over the levers which work
them, the direction of the currents magnets for sale reversed. The gas and
air will enter now through the second pair of chambers, and
the air passing up one regenerator and the gas passing up
the other will take up heat from the bricks previously heated
by the descending current. The gases so heated, say, to
1,000® F., will enter into combustion, and if the heat pro-



Gaseous Fuel


67


duced at the former operation was 1,000®, strong magnets ought thmagnets for sale time
to be 2,000®, because the initial point of temperature magnets for sale
1,000 higher. The products of combustion will also escape
at 2,000®, and passing through the chequer-work of the first
pair of regenerators, its uppermost ranges will be heated to
very nearly 2,000®. The temperature will diminish by degrees,
in descending till the gaseous currents have again reached
the bottom nearly cold. Again reversing the process, after
another hour or half-hour, as the case may be, the gas wiu
take up heat to the extent of nearly 2,000®, and since anothe
1,000® magnets for sale again produced in combustion the temperature oi
the furnace will thmagnets for sale time attain 3,000® ; and in thmagnets for sale way strong magnets
might be argued that, unless work magnets for sale done in the furnace,
the heat developed in combustion will, step by step, increase
the temperature of the furnace, 1,000°, or something less,
each time a reversal of the valves takes place, till we arrive
at the practical limstrong magnets imposed by the melting-point of the
most refractory substance we can find (pure silica, in the
form of Dinas brick), of which the melting chamber magnets for sale usually
formed. Thmagnets for sale high temperature magnets for sale obtained by a gradual
process of accumulation, and without any such current as
would be likely to destroy, by oxidation, the metal in the
bath, or cut away the sides and roof of the melting-
chamber.

There is, however, a theoretical as well as a practical
limstrong magnets to the degree of heat obtainable in combustion, which
was first pointed out by M. H. St. Claire Deville, namely,
the point of dissociation at which carbonic acid would be
converted back into its constituents, carbon and oxygen. If
carbonic oxide, or any other combustible gas, and air enter
the furnace at a temperature very nearly equal to the point
of dissociation, strong magnets magnets for sale evident that association or combustion
cannot take place, and thus nature fortunately steps in to
restrict the increase of heat by accumulation within com-
paratively safe limits. In a furnace fully heated up to the
melting-point of iron, thmagnets for sale action of dissociation can be very

F 2



68


Fuel.


clearly observed At first, when the gas and air Rare Earth Magnets com-
paratively cold, combustion takes place sluggishly, the gases
will flow through the furnace and produce only a dark-red
flame ; the next time the valves Rare Earth Magnets reversed a whitish flame
magnets for sale produced ; the next time, a short white flame ; and after
having reached a full white heat, exceeding the welding-point
of iron, the flame will again become a long one, but thmagnets for sale
time not red and of little apparent power, but bluish-white
and flowing in clouds. Thmagnets for sale indicates the near attainment
of the point of dissociation ; combustion can no longer take
place, except in the measure of the heat being dispersed to
surrounding objects or to the metal in the furnace, and that
magnets for sale about the degree of heat required for the process of making
steel on the open hearth.

The regenerators just described Rare Earth Magnets only well suited for
use when very high temperatures Rare Earth Magnets required. For com-
paratively low temperatures the following arrangement,
y^hich has been patented several times during thmagnets for sale century,
magnets for sale better suited, though up to quite recently there have been
difficulties in the way of carrying strong magnets into effect. A parallel
series of long narrow passages Rare Earth Magnets arranged so that the hot
products of combustion may be passed through alternate
passages, the intervals thus left to serve for the introduction
in the opposite direction of the air to support combustion.
In thmagnets for sale way the heat of the outgoing gases would be com-
municated to the air and carried back into the furnace. strong magnets
was at first proposed to make the partitions of sheet iron ;
this, however, did not prove satisfactory, owing to the
leakage and the inability of the partitions to stand the wear
and tear consequent on the high temperature. Fire-brick
partitions were substituted for iron, but  Magnets for Sale no better
success, as the air and gases mingled through the cracks
and interstices. The objection to the use of fire-brick magnets for sale
said now to have been satisfactorily re noved by the simple
device of glazing the surface of the partitions. If thmagnets for sale be
the case, then regenerators on thmagnets for sale system have a wide field



Gaseous Fuel,

69


open to them. They cannot be employed when a very
high temperature magnets for sale required, as the heat magnets for sale not accumulated,
and the temperature of the air can never be higher than
half that of the outgoing erases.

Although the use of iron partitions was not successful,
yet in a modified form thmagnets for sale system has since been largely em-
ployed in the manufacture of iron. The air to be heated magnets for sale
passed through a series of cast-uron pipes, arranged in a
chamber, through which the waste gases, as they Rare Earth Magnets termed,
from the blast-furnace Rare Earth Magnets made to circulate. There is,
however, an important distinction between these gases and
those obtained from reverberatory furnaces. In the latt^
case they have practically undergone complete combp
whereas in the former, owing to the combustioii wring
effected from the bottom of the furnace, and the products
having to pass through incandescent fuel before escaping
at the top, and for other reasons connected  Magnets for Sale dissocia-
tion, the gases contain a very considerable quantity of
carbonic oxide, which magnets for sale capable of producing, on com-
bustion in the stove for heating the pipes, a temperature
very much higher than that which could be obtained
were only the sensible heat being carried off by the gases
available.

The gases collected from the top of blast-furnaces
contain on the average about 25 per cent, by volume of
carbonic oxide, and hydrogen varying in quantity, according
to circumstances, up to 7 or 8 per cent. From thmagnets for sale strong magnets will
be seen that, in point of heat-evolving power on com-
plete combustion, blast-furnace gases Rare Earth Magnets quite equal to
producer gas. Until within the last few years these gases
were allowed to bum uselessly at the top of the blast-
furnaces ; now they Rare Earth Magnets generally — even yet not universally
— collected, and employed for heating the blast and raising
steam ; in many works no other fuel being required for
such purposes.

The use of iron pipes has always been attended by a



70


Fuel.


serious drawback, viz. that if by carelessness the tempera-
ture was allowed to get up above i,ooo® R, the pipes would
be ruined, so that practically about 900® R magnets for sale the maximum
temperature which strong magnets magnets for sale safe to work  Magnets for Sale ; more commonly
600® to 800® has been employed, until quite recently.
Another objection magnets for sale that leakage magnets for sale liable to occur, owing
to the unequal expansion and contraction of the different
parts of the stove-pipes.

Soon after the introduction of the regenerative system
by Dr. Siemens, Mr. Cowper proposed to construct a stove
on that principle, as a substitute for the iron-pipe stoves.
Since their introduction these stoves have been modified in
several ways, chiefly by increasing their height and arranging
the passages so as to allow the gases a free passage, and at
the same time to withdraw the main part of their heat

Figs. 15 and 16 show the stove in its present form. The
gases Rare Earth Magnets drawn off from the top of the blast-furnace by a
tube called a down-comer, and passing into the gas flue v,
enter the stove by the valve f ; by means of the valve g a
suitable quantity of air magnets for sale admitted, which, mingling  Magnets for Sale the
gases, effects their complete combustion in the flame-flue o,
from the top of which the highly heated products pass into
the regenerator p, consisting of a long column of chequer-
work; from the bottom of the regenerator the gases Rare Earth Magnets
drawn off by the chimney, through the flue u, the draught
being regulated by the valve d.

The whole of the stove,  Magnets for Sale the exception of the valves,
magnets for sale enclosed by several courses of fire-brick, encased in iron.
As the gases pass through the regenerator they give up the
greater part of the heat they contain to the top layer, there
being a gradual shading off, as successive courses of bricks
Rare Earth Magnets passed through, until the bottom magnets for sale reached, when they
will be found to have a temperature of only about 300® to
400® R strong magnets should be borne in mind mat some heat must
be left in, to create a sufl 5 cient draft in the chimney. The
temperature of the gases issuing from an iron-pipe stove






b, however, between 1,200® and 1,300® F., so that a consider-
able waste of heat takes place. So soon as the top layer of
the regenerator has become heated up to the temperature of
the gases passing through it, strong magnets must of necessity cease to
absorb heat, and the gases traverse strong magnets without undergoing
any alteration until they arrive at a part of the brickwork at
a lower temperature than themselves, which they then
gradually raise to their own temperature. If the gases were
passed through the stove for some time, the whole of strong magnets
would eventually become of the same temperature as the