AN IMPROVED STEAM BOILER
Year: 1842

page_text: HALL'S
SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
HALL, of Dartford, in the County of Kent, Civil Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Eleventh day of January, in the Fifth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said Edward Hall,
Her especial licence that I, the said Edward Hall, my executors, administrators,
and assigns, or such others as I, the said Edward Hall, my executors, adminis-
trators, 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; and vend, within England, Wales, and the
Town of Berwick upon Tweed, my Invention of "AN IMPROVED STEAM BOILER;"
in which said Letters Patent is contained a proviso obliging me, the said Edward
Hall, 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 enrolled in Her said Majesty's
High Court of Chancery within six calendar months next and immediately after
the date of the said in part recited Letters Patent, as in and by the same, refer-
ence being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Edward Hall, do hereby declare the notice of my said Invention of "An Im-
proved Steam Boiler" to consist in the application of one or two side tubes to
an ordinary cylindrical tube boiler, so as to extend the heating surface and pro-
duce the effects of a larger boiler without augmenting the space ordinarily
occupied by one of smaller size. These external, or, as I call them, feed
heating tubes, are placed in the side flue or flues of an ordinary cylindrical tubo
boiler and are connected to the boiler as well as to its lower fire tubes, and the
water made to circulate thro' them, as-herein-after explained. And in further
compliance with the said proviso, I, the said Edward Hall, do hereby describe
the manner in which my said Invention is to be performed by the following
statement thereof, reference being had to the Drawing annexed and to the
figures and letters marked thereon, that is to say :-
DESCRIPTION OF THE DRAWING.
Figure 1 represents a side elevation of a cylindrical tube boiler and brick
seating taken through the side flues, with the feed heating tube A, A¹ lying in
the flue, and which are supplied with the feed water by means of the pipes B
at the back, and whence it flows round and past the neck pipe C as far as the
stopper D, and then ascends through the top of the tube A, A", at a into the
pipe E, to escape and mix with the water of the boiler G at its other extremity E.
"The front ends A¹ of these tubes receive their water from the lower or fire
tubes F, F, which are fed from the boiler Gabove them through the neck pipe C.
Figure 2 represents a transverse section of a tuble boiler taken at the back of.
the fire-place, and exhibits the arrangement of the two feed heating tubes A, A,
in the sides, flues in connexion with the fire tubes F, F, F, beneath, and the
boiler G above them, which are represented by similar letters in Fig. 1.
Fig. 3 represents 'a plan of the boiler and seating, with the upper flucs
uncovered, which parts are also designated by similar letters as in Fig. 1.
B, B, mark the feed pipes; A, A³, and A, A¹, the two feed heating tubes,
which are now exposed to the action of the heated air in the flues and
convey the feed water to the pipes E, E¹, and E, E¹, to the inside of the
boiler G; c, c, the neck pipes of the tubes, which prevent the feed water
from mixing with that which is passing down to the lower tubes F from the
boiler G. Figure 4 represents a vertical section of the boiler without the brick
seating, and taken through the feed heating tube, the fire tube below it, and the
boiler above, similar letters representing the similar parts, as in Fig. 1. B, the
feed pipe connected to the back ends of the feed heating tubes A, A¹, which

page_text: convey the feed water as far as the stoppers' D, and thence up and along the
inner pipe E, E', whence it escapes to mix with the water in the boiler. The
stopper D is adjusted so as to be removed by means of the handle m when
required for clearing the boiler of sediment. During this operation the water
from the boiler is passing down the neck pipes C, C, and up again into the boiler
through the necks H, H. In carrying this improvement into effect I do not find
it necessary to confine myself to any particular dimension of boiler or number
of tubes, or attachment of them to one another, but by preference I make each
of the two feed heating tubes of the same size as the lower tubes, and about
the same length. In their construction, I prefer fixing each of the two feed
heating tubes to the boiler at both ends, and making them an integral part of
the same, then connecting these tubes to the lower. tubes by a flanched neck
towards each end, which are secured together with screen bolts. I do not claim
the use of what I have called feed heating tubes in the flues of boilers generally,
as they are known to have been used before, but their application to cylin-
drical boilers with tubes below them in the fire, as here described, is new;
that is, feed heating tubes connected with the tubes beneath cylindrical boilers
and interposed between them and the boiler without the feed water passing
through them being allowed to mix with the water of the lower tubes in its
passage into the boiler; and it is to such application and arrangement I ground
my Patent for an improved steam boiler which, having within itself the means of
heating its feed water approaching to or exceeding the point of ebullition, is
productive of very considerable economy in the fuel necessary for generating a
given quantity of steam compared with boilers without such an appendage.
And such my Invention being, to the best of my knowledge and belief, entirely
new and never before used within that part of Her said Majesty's United
Kingdom of Great Britain and Ireland called England, Iler said Dominion of
Wales, and Town of Berwick upon Tweed, I do hereby declare this to be my
Specification of the same, and that I do verily believe this my said Specification
doth comply in all respects, fully and without reserve or disguise, with the proviso
in the said herein-before in part recited Letters Patent contained, wherefore I
hereby claim to maintain exclusive right and privilege to my said Invention.
In witness whereof, I, the said Edward Hall, have hereunto set my hand
and seal, this Eleventh day of July, in the year of our Lord One thou-
sand eight hundred and forty-two.

page_text: AND BE IT REMEMBERED, that on the Eleventh day of July, in the
sixth year
of the reign of Her Majesty Queen Victoria, the said Edward
Hall came before our said Lady the Queen in Her Chancery, and acknowledged
the Instrument aforesaid, and all and everything therein contained and specified,
in form above written. And also the Instrument aforesaid was stamped accord-
ing to the tenor of the Statute made in the fifty-fifth year of the reign of His
Majesty King George the Third.