Weekly national intelligencer., 1847-09-25

with so much the greater readiness in that the
writer is citizen known TO us to be possessed Of
such experience in whatever concerns the theory
and practical knowledge in Mechanics, that we
place very great reliance upon his judgment in all
such matters.
Messrs Eprrons--I your paper of the 7th instant
notice article taken from Hunts Merchants Magazine
headed Montgomery newly invented Steam Boiler" and
have had the pleasure Of witnessing the operation of the
boiler in question: beg the privilege Of bearing my humble
testimony the merits Of this valuable inventions particularly
its good qualities due entirely principles variance
with the neestabshed practice in the construction and
management of boilers The notice in question does
give the nature of the improvements but merely
the estimated saving in fuel andspace the reduced quantity
of employed, and the prevention of explosions AS
such the objects aimed at y all inventors of new
provements in boilers they generally claimed and
announced having been accomplished and therefore such
notices almost invariably by any
ing satisfy the thinking reader that the notice is other than
puff of what may never be realized.
As deem the present invention Of merit wish
simply to describe the principles which is based and the
rationale Of its operations The plan heretofore generally
pursued to apply the greatest heat to the lowest part of the
boiler and the products of combustion ecede from the
FIRE and the heat becomes less intense carry them through
ues in the upper part of the boiler that the heat applied
to the water greatest at the bottom and gradually less to-
wards the top This mode Of procedure has foundation
in science sound reason but has been bndy followed for
years. simply because commenced. The hottest
water being the expanded and, therefore, the lghtes
will naturally rise to the surface, the colder, by circulation,
passing down to take its places hence the hottest water will
be the top. That this is will deny
Here then have the first absury presented by the old
systematic greatest heat applied the water where seeks
economically from water under the control of this law, the
most intense heat should be applied to that pant of the water
which has been heated the highest point for then the heat
will be mainly employed in Transforming the water into
steam while the heat of less intensity will be carried down
prepare the water for the evapoang process In this way
the products Of combuston they decrease temperature
communicate their caorc to the water for, in descending
they continue to with bodies of less and less tempea
ture which will thus continue receive heat. The truth of
this will be rendered evident by extreme We will
suppose the water to be of such depth that the surface
will be 2I2 degrees the point OF evaporation and the
bottom down 100 degrees and that the products Of
buston leaving the furnace at 800 degrees and
gradually reduced to $50 degrees where the ues leave the
If applied in the old method the heat of 800 degrees
the fues would be applied the water OF 100 degrees
while that of $50 degrees the already 2l2 de-
grees from which it follows that the ends of the ues the
smoke and other products of combustion would, being
less temperature than the water abstract heat from instead
of transferring heat TO it; hence portion of the heat pre-
viousy applied must be distracted and wasted.
But this mode of applying the heat and suppose
the heat of 800 degrees to be applied the water of 2l2
and the heat Of $50 to be applied the water at l00 and
follows that throughout the process the products of
combustion will be giving out heat TO the water instead OF
giving out heat during portion OF the time and absractng
il during the remainder We have here this particular
comparison Of the old plan with Mr.. Montgomery sys-
He has thrown aside the old method necessarily alb
sud and adopted the other whchs rational and economical
But economy Of heat is all that attained by this
system. When the greatest heat is applied the bottom the
Of mn
greatest heat being applied at the boom where the water
seeks to be the coolest the vapo must be mainly generated at
the bottom and forced up through the OF water above
tending TO force the water with and the concentrated
vapo the bottom of the being held down by the
pressure Of the column and that of the previously generated
seam seeks constantly to berate itself from the superncum
bent pressure from which it follows that when steam dis
charged from the top by opening any Of the valves the pres
the surface of the water which is Immediately under
the aperture through which the escapes, suddenly
removed. As natural consequence the pen-up steam at
the bottom being relieved of part of the PRESSURE suddenly
flies up forcing with the water, which is thrown with great
violence in the form of foam spray, frequently running
overn the engine And if by accident the steam above
should have been surchaged with caorc the comminuted
particles OF water insananeousy absorb this surplus heat
and Immediately transformed into immense volume of
seam often producing degree of pressure greater than the
boiler withstand explosion therefore follows with all its
dire consequences.
But suppose, the other hand the heat to be applied in
the reversed manner, the greatest intensity at the top and
gradually reduced towards bottom, the water will be ga-
duay heated from the bottom towards the top the circulation
will be gentle and natural, and the steam being generated
mainly at or near the top will be evolved without violence
and should the superintendent pressure be suddenly
moved the steam will escape without effort and without
evil of will not be thrown up
there will be pressure below In this way the heat is
gradually transferred from the products of combustion TO the
water and the steam is liberated without difficulty, the
having no tendency to rise with il.
The mineral substances held in solution or in mechanical
suspension in all waters form incrusaons boilers which
not only retad the evaporang by their non-conduct
ing properties but often endanger the safety of boilers and
IN salt water this evil is so that portion OF the concen
raed water must be discharged given intervals to be
of water in the boiler from reaching that point of concena
ton satuaton at which the salts deposited Of
the discharge of the heated and the substitution Of cold
is wastefu of heat II
Mr.. Montgomery has arranged his boiler and so
ages the heat that current of the rises the
middle in series Of vertical tubes and descends towards
the outside said deposng all sedmentary matter
in the lower parts Of the bottom of boiler where
bow-of valves which, when opened permit the immediate
discharge of these impurities with very little loss Of water
But the establishment of this circulation has another import
ant effect The heat being mainly applied to the vertical
tubes through which the water ascend the gobues OF vpor
that found at the surface the will be liberated and
carried to the surface OF the water by the upward current
and thus rapid liberation Of all the steam generated is
ensured.
By these improvements danger of explosion is greatly
duced the mode of applying the heat will prevent the
water from being thrown up, (techncally called "pnng
which is recognised the chief cause of explosions The
heat applied economically as pointed out above the
bulk Of the boiler much reduced by the successful appca