A. NEW OR IMPROVED METHOD OR METHODS OF RAISING OR PRODUCING STEAM FOR THE PURPOSE OF WORKING STEAM ENGINES AND OTHER APPARATUS
Year: 1819

page_text: SEAWARD'S SPECIFICATION..
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
SEAWARD, of the Kent Road, in the Parish of St. George's, Southwark,
sendeth greeting.
WHEREAS His most Excellent Majesty King George the Third, by His
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, thic Third day of April, in the fifty-ninth year of His reign, did,
for Himself, His heirs and successors, give and grant unto me, the said
John Seaward, His especial licence, full power, sole privilege and authority,
that I, the said John Seaward, my exors, adñiors, and assigns, or such others
as I, the said John Seaward, my exors, aditiors, and assigns, should at any
time agree with, and no others, from time to time and at all times during the
term of years therein expressed, should and lawfully might make, use, exercise,
and vend, within England, Wales, and the Town of Berwick-upon-Tweed, my
Invention of "A. NEW OR IMPROVED METHOD OR METHODS OF RAISING OR
PRODUCING STEAM FOR THE PURPOSE OF WORKING STEAM ENGINES AND OTHER
APPARATUS;" in which said Letters Patent there is contained a proviso obliging
me, the said John Seaward, by an instrument in writing under my hand and
seal, particularly to describe and ascertain the nature of my said Invention,
and in what manner the same is to be performed, and to cause the same to be
inrolled in His Majesty's High Court of Chancery within six calendar months'
next and immediately after the date, of the said recited Letters Patent, as in

page_text: and by the same, reference being thereunto had, will more fully and at large
appear.
NOW KNOW YE,. that in compliance with the said proviso, I, the said
John Seaward, do declare that the nature of my said Invention, and the
manner in which the same is to be carried into effect and performed, is
described as follows, that is to say "
I place a tube or combination of tubes made of cast iron, or any other
proper material, of sufficient strength to resist the expansive force of the steam
intended to be employed in a furnace or furnaces, (either horizontally, vertically,
or otherwise, as convenience may suit, and connect one end of the tube or
combination of tubes with the working cylinder of the steam engine or other
apparatus, as the case may be, by the nosle or steam passage, similar to a
common boiler. To the other end of the tube or combination of tubes I fix a
small feed pipe, with a valve or cock and regulator, for the supplying the
necessary quantity of water in a continuous stream, which, being forced in in
due quantity, is rapidly converted into steam when it comes in contact with the
internal surface of the heated tube or combination of tubes, and the steam thus
generated will rush forward-with uniform celerity to perform its office in the
working cylinder of the steam engine or other apparatus to which it is applied;
but it is necessary to observe that the heat, should be so regulated that the
water may not be decomposed when the apparatus is used with a low-pressure
engine. Although the tube or combination of, tubes, both as to shape, and
size and the mode of disposing them in the furnace or furnaces, may be varied
many ways, I prefer a cylindrical tube of uniform diameter, passing backwards
and forwards four or five times through the furnace, in an horizontal position,
which I call, for the sake of distinction, a salamander, and as represented in
Fig. 1, the upper part of the furnace being taken off to shew the situation of
the tube, which for convenience is formed in five pieces, connected together by
flanges (x, x, x, x,) or otherwise. (a) the safety valve; (c) the end of the tube,
which is to be connected with the working cylinder- of the steam engine or
other apparatus; (Z). the regulator; (g), the feed pipe. The parts of the
salamander more immediately exposed to the action of the fire I make stronger
than those which are set in the brickwork, which is distinguished by being
coloured red.
H
ן
***
Fig. II. is a vertical section of the salamdar-and furnace, in direction
from A to B on the plan, shewing the situation of the chimney tube (6), the
fire-place (c), and fire door (d), and also the safety valve (a). The flue (6) is
surrounded by another tube or casing; for the purpose of, containing water for
the supply of the salamander. This casing may be of sufficient altitude, so that

page_text: the column of water contained therein shall be of sufficient weight to supply
the salamander without any other force; but in high-pressure engines it would
be inconvenient to employ a feed head of sufficient altitude, therefore the water
must necessarily be forced into the salamander by a forcing pump; or by some
similar contrivance, for although the water casing would be employed with
considerable saving of fuel, it is not an indispensable part of the apparatus, and
in the case of low-pressure, engines, the water from the air pump should be
used for that purpose: The places shaded dark is the space for the fire to play
round the strong tube or salamander.
*
Fig: III. is another vertical section of the salamander and furnace in the
direction from C to D, on the plan' across the fire-place (c), shewing the fire
bars (e, e, e); the safety valve (a), and the branch (f), to connect with the nosle
of the working cylinder of the steam engine.
Fig IV is also a vertical section of the same, in direction from E to F on
the: plan; shewing the end of the strong tube or salamander, with the feeding
apparatus (g,g), the feed piper communicating with the lower division (r) of
the water casing (h), the stopcock, which is opened and shut by the handle (i),
being connected by a rod to the lever (k), which is raised or depressed by the
rising or falling of the piston (m) in the small cylinder (l); this communicating
with the interior of the salamander by the passage (0, 0). The steam in the
salamander: will; when too strong, (or rather) too much in quantity, arising.
from too considerable a supply of water, force up the piston, which, shutting off
the cock (h), will of course:diminish or stop the supply of water. The piston
is forced down either by afproperly adjusted spring or by a weight partially
immersed in water; the specific gravity of the weight being rather more than'
that of the water. The cylinder (7) will also answer the purpose of a steam
guage and of adsafety valve, for when the piston (m) is forced above the
aperture (n), the steam will blow off. The conical plug (p), which is regulated
by the thumb screw (9); is for the purpose of casting the stream of water
round in a thin sheet inside the tube, and when the engine is to discontinue
working, the supply of water is to be stopped either by closing this plug or by
shutting off the cock (h). The water casing may be divided in two or more
compartments or divisions; asr, s, t, in Fig. II., and partially in Fig. IV.; but
communicating, with each other by the pipesu, v. Thus the pipe u connects-
the upper part of the division with the lower part of the division (s). In
like manner the pipe (v) forms a communication between the two divisions (r
and s). By this contrivance the colunin of water will not be impeded from
passing downwards, but there will be effectually prevented that rapid circulation'
which always takes place among the particles of a body of water when ex-

page_text: posed to the action of heat, and by which every portion of the water acquires
almost simultaneously the same temperature.
The water in the lowest
division being nearest the fire will be the hottest, while that in the upper
division supplied from the forcing pump will be the least heated. I do also
raise or generate steam for working locomotive engines and steam carriages,
and for other purposes where steam is required, by inclosing a mass of metal
or other proper material, but I prefer cast iron previously heated to a high
temperature in a strong vessel sufficiently capacious and of any convenient
form, and a stream of water being injected into the vessel upon the heated
metal or substance, a volume of steam will be generated fully adequate for
working a steam engine, or for other purposes.
Fig. V. is a longitudinal section, and Fig. VI. is a transverse section of this
kind of salamander, inclosed in its recipient vessel of cylindrical form (though
any other convenient figure will answer nearly as well). The mass of cast iron
(9,9, 9, 9). The two
is, for the sake of convenience, divided into four pieces
passages (ff) leading from the vessel are to convey the steam to the working
cylinder. The stream of water is supplied by the feed pipe (a, a), and is
regulated by the piston () moving in the small horizontal or other cylinder
(d), which is pressed down by an adjusted spring. The end (c) of the piston
rod being connected by means of a joint to a lever, opens the cock (6), and
admits a plentiful supply of water; but when the supply of water is too con-
siderable, and in consequence too much steam is generated, the piston will be
forced up, and the cock gradually shut off, while the superabundant steam will
escape by the aperture (e).. The feed of water is to be supplied by the
forcing pump (i), to the chamber of which is attached the cylinder (1), with its
piston pressed down by a strong spring. By this means the water will be
forced in in nearly an uniform stream, but if the pump gives too great a supply
the superfluous water will be discharged at the aperture (m).
Fig VII. and VIII. are a longitudinal and transverse sections of a sala-
mander, similar to the one last described, but inclosed in a double vessel or
casing. The supply water, regulated as before mentioned, will be forced into
the space (n, n,) between the two casings, where it will be evaporated into
steam, but not so rapidly as when injected immediately upon the heated
iron or other substance. The recipient vessels or casings employed for this
description of salamander must be strengthened in proportion to the pressure.
they are intended to bear, but this may be done at a very moderate expence,
because a vessel required to hold a salamander for working an engine need
not be more than one third the diameter and length of a common boiler
requisite for the same engine and apparatus, constructed as herein-before