A JUNCTION OF TUNNELS IN A BOILER, FOR THE PURPOSE FOR LESSENING THE APPEARANCE OF SMOKE, AND FOR LESSENING THE CONSUMPTION OF FUEL, AND FOR SUCH ORIGINAL FLUES AS MAY BE PLACED IN SUCH BOILER OR THE FURNACES ATTACHED THERETO
Year: 1818

page_text: FRASER'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
FRASER, of Long Acre, in the Parish of Saint Martin's in the Fields, In the
County of Middlesex, Engineer and Coppersmith, send greeting.
,
WHEREAS His Royal Highness the Prince Regent, for, and on behalf of
His most Excellent Majesty King George the Third, by Letters Patent under
the Great Seal of Great Britain, bearing date at Westminster, the Twelfth
day of November, in the fifty-ninth year of His reign, did, for Himself, His
heirs and successors, give and grant unto me, the said James Fraser, His
special licence, that I, the said James Fraser, my exors, adñiors, and assigns,
or such other as I, the said James Fraser, my exors, adññiors, or 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, & vend, within England, Wales, and the Town of
Berwick upon Tweed, my new and original Invention of "A JUNCTION OF
TUNNELS IN A BOILER, FOR THE PURPOSE FOR LESSENING THE APPEARANCE OF SMOKE,
AND FOR LESSENING THE CONSUMPTION OF FUEL, AND FOR SUCH ORIGINAL FLUES AS
MAY BE PLACED IN SUCH BOILER OR THE FURNACES ATTACHED THERETO;" in which
Letters Patent there is contained a proviso obliging me, the said James Fraser, by
an instrument in writing, under my hand and seal, particularly to describe, and
ascertain the nature of my said Invention, and in what nianner the same is
to perform, and how to be made, and to cause the same to be inrolled in His
Majesty's High Court of Chancery within two calendar months next and

page_text: immediately after the date of the said recited Letters Patent, as in 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
James Fraser, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be made to perform, is described and
ascertained in the Drawing hereunto annexed, and that my new invented
boiler consists of such parts as are described in such Drawing (viz³):-
A vertical with a horizontal tunnel in a boiler, or, in other words, both these
tunnels are in the midst of the water. The horizontal tunnel is the supposed
fire-place, and the vertical tunnel supplies the horizontal with fuel from above,
so that the fire is immediately under the vertical tunnel, on the top of which
is a door and register; also when the smoke is required to be burned, this
register will admit of sufficient air to effect combustion and beat the smoke
down into the ignited coals, and thereby lessen its quantity. The vertical hop-
per will also supply the boiler with a quantity of coals, so that for ordinary
purposes, such as for heatings by steam, may be left several hours supplying
itself regularly with coals without attendance; from the junction of tunnels
above mentioned, the fire and hot air descend to the secondary fluc under the
boiler, pass nearly its whole length, from back to front, then turns right hand
and left, under the bottom, to the sides, and then to the chimney. There are
two flues issuing from the fire or horizontal tunnel, which meet the main flue,
and present a more enlarged surface of flame and hot air to the water; and
these flues may be made to pass out at the ends of the boiler, parallel with the
horizontal tunnel, and then be made a common vortex. Bricks also may be
placed at the flues and end of the fire; this will prevent the boiler from being
burned, and will assist in bringing down the regular supply of coals from the
vertical tunnel. The above horizontal tunnel is supposed the primary and
essential flue. What I call the secondary flue, is, in fact, the primary one of
many boilers now in use, and my primary or horizontal tunnel is their
secondary one. But the junction of a horizontal with a vertical tunnel opens
a communication in the inside of a boiler, that, independant of its convenience,
presents many advantages supposed unattainable in ebulition of ten hours con-
tinuance, a more rapid combustion, and an enlarged surface, but, that all may
be as simple as possible, the subjoined Drawings will ensure a complete
knowledge of its structure. And I do hereby declare, that though I conceive
myself to have been the sole and only Inventor of the vertical tunnel boiler,
that such vertical tunnel is not what I call the principal of this my present
Invention, nor the horizontal tunnel either, but the Invention of both,
and the new collateral flues that issue from the sides, for the purpose of

page_text: enlivening the fire and bringing down the fuel contained in the vertical
tunnel.
In building these boilers, it is obvious that when intended for ships or other
purposes where it would be improper to have external heat, the same principle
may be extensively adopted without the incumbrance of brickwork, so that the
manufacturer may easily join the tunnels and side flues, without the bottom,
secondary, or external flue, between the brickwork and boiler.
And I do declare that I do not make claim to the tunnels separately, but
my Invention consists in the junction, and also for the collateral flues that
issuc separately from the sides of the fire through the boiler to the main flue
whereever placed, and that, whether these flues and the horizontal flue or
tunnel decend into the secondary flue, or rise into the shaft direct. And for the
further elucidation of my Invention, and to shew the situation of the tunnels,
the Drawing referred to shews as follows, viz:-
A shews the junction of the horizontal to the vertical tunnel..
B, the flucs, whether direct from the inside of the fire to the outside of the
boiler, or the said flues passing by an angular turn out at the end of the
boiler.
C, the horizontal tunnel connected with the fire-place and the vertical
tunnel at the angles d, d.
E, the secondary flue or under flue, through which the fire descends from
the primary fluc, called the horizontal tunnel; this secondary flue also receives
the heat of the flues B, when they pass out at the ends.
I', the side view of the horizontal partition that compels the contents of the
horizontal tunnel and new flues to descend to the under or secondary flues, the
flame of which is seen to issue out at e; it then traverses the sides of the boiler
and passes out into the chimney or shaft at f; when the flues B pass out direct
to the outside of the boiler, they connect with the heat of the flame E, and
pass to the shaft also at f.
G, G, the doors of the fire-place.
II, a door for the purpose of cleansing or inspecting the lower or secondary
fluc.
K, the ventilator and door that covers the vertical flue, supplies fucl, or
regulates heat by the admission of air down to the fire.
L, L, two pipes and plugs to clean the inside of the boiler.
M, the man-hole.
N, the sides of the boiler laid bare, to shew the action of the flame from the
flue e and the flue B, both going into the shaft f.
O, end view, shows the flues f, going to the shaft or chinney.

page_text: The front view shews the doors off the fire on the bars; vertical tunnel
filled with coals; and the flues B, at the top, joined to the flues e, which is seen
to issue from behind the bricks.
In witness whereof, I, the said James Fraser, have hereunto set my hand
and seal, the Twelfth day of January, One thousand eight hundred and
nineteen.
AND BE IT REMEMBERED, that on the Twelfth day of January, in
the year of our Lord 1819, the aforesaid. James Fraser, came before our said
Lord the King in His Chancery, and acknowledged the Specification afore-
said, and all and, every thing therein contained and specified, in form above
written. And also the Specification. aforesaid was stamped according to the
tenor of the Statute made for that purpose.
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