A NEW METHOD OF SETTING BOILERS FOR STEAM ENGINES, PANS FOR MELTING LEAD, TIN, PEWTER, AND OTHER METALS OF EASY FUSION, AND A NEW MODE OF DISCHARGING THE PANS FOR MELTING LEAD, TIN, PEWTER, &C. AS BEFORE NAMED WHEN FULL, AND SETTING COPPERS AND BOILERS OF EVERY DESCRIPTION
Year: 1808

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, J, THOMAS
PRESTON the younger, of Tooley Street, Southwark, in the County of Surrey,
Lead Merchant, send greeting.
WHEREAS His most Excellent Majesty King George the Third, did, by
His Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twenty-sixth day of
January, in the forty-eighth year of His reign, give and grant unto me, the
said Thomas Preston, my executors, adñiors, and assigns, His especial licence,
full power, sole privilege and authority, that I, the said Thomas Preston, my
executors, adiñors, and assigns, during the term of years therein mentioned,
should and lawfully might make, use, exercise, and vend, within England,
Wales, and the Town of Berwick upon Tweed, my Invention of "A NEW
METHOD OF SETTING BOILERS FOR STEAM ENGINES, PANS FOR MELTING LEAD, TIN,
PEWTER, AND OTHER METALS OF EASY FUSION, AND A NEW MODE OF DISCHARGING THE
PANS FOR MELTING LEAD, TIN, PEWTER, &C. AS BEFORE NAMED WHEN FULL, AND
SETTING COPPERS AND BOILERS OF EVERY DESCRIPTION;" in which said Letters
Patent there is ontained a proviso obliging me, the said Thomas Preston, by
an instrument in writing under my hand and seal, to cause a particular de-
scription of the nature of my said Invention, and in what manner the same is
to be performed, to be inrolled in His Majesty's High Court of Chancery within
four calendar months after the date of the said recited Letters Patent, as in and
by the same (relation being thereunto had) may fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, 1, the said
Thomas Preston, do hereby declare that my Invention consists in setting
boilers, lead pans, &c., in such a position that the fire may have free access
to every part of them without conducting the flame round. the sides by a
wheeling or winding flue by a partial draft leading from the fire-place under
the boiler by one or more small openings; that the boiler or pan be placed
at a convenient distance immediately over the fire-place upon as many small
bearings as will be sufficient to support it properly, leaving the fire to arise
freely on every side of the boiler or pan. The smoak is to be carried off' to
the chimney through an aperture of a convenient size, which is to be placed
as near the upper part of the flue as possible, and to be regulated by a damper.
This aperture will be better situated at the extreme end, opposite the feeding
hole of the fire-place. The Drawings A, Figure one, two, and three, hereunto
annexed, will serve to elucidate the foregoing description. Figure one is the
ground plan of a boiler for a steam engine; A, the boiler; B,B,B,B, the
opening or flue betwixt the boiler and the brickwork; C, C, C, C, the brick-
work; D, D, flue leading to the chimney; E, the damper; F, the chimney
flue; G, G, G, brickwork of chimney; a, a, a, a, a, a, the lumps supporting
the boiler, shewn by the dotted lines; L, the happer for feeding the fire,
shewn by the dotted lines; b, b, b, b, fire-place, shown by the dotted
lines. A, Figure two, is a side view section of the same boiler; A, A,
the boiler, the line across from C to C shewing the heighth of the water;
B,B, the opening or flue betwixt the boiler and the brickwork; C, C, C, C, C, the
brickwork; D, D, the flue leading to the chimney; E, the damper, partly drawn
up; F, the chimney flue; G, G, the brickwork of the chimney; H, the fire-
place; I, the fire bars; K, K, K, the bearing bars; L, the happer hole to feed
the fire; M, M, M, brickwork covering the upper part of the boiler, leaving a
small space of about three inches betwixt the boiler and brickwork, as at
N, N, N, N; 0, 0, a cast iron plate to cover the flues, which may likewise be
covered in with any other matter or substance equally suitable, and to stop
the fire from rising higher than within about three or four inches of the water
line. The covering, if of cast iron, might be about one inch thick, and should
he cast in two or more separate pieces to prevent its flying from the heat, and
should be rabbited at the joints. I would not have the plate placed quite
close against the sides and ends of the boiler, but a small opening must be
left for a sufficient quantity of hot air to pass over and round the ends of the
upper part of the boiler through the space N, N, N, N, to keep the steam
from being chilled; an opening may be made at the top of the brickwork to
regulate this; P, the arch to give air and save brickwork; Q. a small space
of about two inches betwixt the upper part of the furnace bars and the plate

page_text: which supports the brickwork over the ash hole. A, Figure 3, end view section
of same boiler; A, A, the boiler; B, B, opening or flue; C, C, C, C, brick-
work; H, fire-place; I, fire bars; K, bearing bars; M, M, M, brickwork
over the boiler; N, N, N, space betwixt the brickwork and upper part of
boiler; 0, 0, cast iron plate to cover flues; C, C, water line; a, a, the lumps
supporting the boiler, shewn by dotted lines. For melting lead, tin, &c. I place .
the pans exactly in the same position as the boilers before described, only that
I bring the fire fairly over them, the smoke being carried off, as before men-
tioned. The Drawings B, Figure 1, 2, 3, and 4, are four views of a melting
pan for lead, &c. Figure 1, ground plan; A, the melting pan, of cast iron
or any other fit material; B, B, B, B, the opening or flue; C, C, C, C, the
brickwork; D, the spout for discharging the pan; E, a hopper made of cast
iron or any fit material round the spout to preserve the brickwork; F, F, flues
to the chimney; G, the damper; H, the chimney flue; I, I, I, brickwork of
chimney; O, hopper for feeding the fire, shewn by the dotted lines; a, a, a, a,
fire-place, shewn by the dotted lines; b, b, b, b, four lumps to support the pan,
shewn by the dotted lines. B, Figure 2, shews a side-view section of the
melting pan; A, the pan; B, B, opening or flue; C, C, C, C, brickwork;
F, flue to the chimney; G, damper; HI, chimney flue; I, I, brickwork of
chimney; K, furnace bars; L, L, bearing bars; M, M, iron cover; N. iron
door in the cover; 0, 0, two cast iron hopper holes; the upper one to admit
of a slice or poker, and the lower one to feed the fire; P, the fire-place;
C, C, C, C, four doors of cast iron or any other fit material to the two hopper
holes O, O; b, b, the lumps supporting the pan, shewn by dotted lines; Q, the
arch to give air and save brickwork. B, Figure 3, is an end view section of
the pan; A, the
pan; B, B, opening or flue; C, C, C, C, brickwork; D, the
spout; E, iron hopper round the spout; K, furnace bars; L, bearing bars;
M, M, iron cover; N, door to cover; P, fire-place; Q, a lever (of a convenient
length) with a plug at the end next the spout to stop up the mouth of the
spout till the pan is required to be discharged; R, the screw nutts and spindle
upon which the lever Q is marked; S, the plug attached to the lever Q, to
which it is fastened by a key at a; T, the extreme end of the lever; V, a
weight in which may be moved upon the lever Q; W, a vessel of any con-
venient form to receive the discharge from the pan. B, Figure 4, is the iron
cover; M, M, the cover cast in two peices, the division of which is shewn
at a, a, a, a; N, the door. When the pan is required to be discharged the
weight should be drawn down to that end of the lever next the furnace, and
the end at T raised up, which will of course draw the plug; the reverse of this
should be adopted in closing it again.

page_text: The foregoing I conceive will be sufficiently explanatory of the nature of
my Invention. Though I have made all my drawings to a certain scale, they
will of course admit of much variation in point of dimensions and proportions
without deviating from the principle I have here explained. This principle
will be applicable to boilers of every description, namely, that of placing the
copper or boiler as it were in the midst of the fire, and confining the heat with
which it is enveloped as closely as possible. With respect to the pans for
melting metal they will answer the purpose of a reverberatory furnace only in
a more advantageous manner, the flame wholly enveloping the matter to be
fused, by which means the fire not only does its duty more expeditiously, but
likewise with much less injury to the furnace. For a plumber's use or where
a great heat is not wanted the iron cover may be brought nearly close down
upon the edges of the pan. It may be proper to observe, that the pan and flues
may be covered over by any other substance or material capable of confining
the heat, and that will admit of the pan being worked with equal convenience.
In witness whereof, I, the said Thomas Preston, have hereunto set my
hand and seal, this Twenty-sixth day of May, in the year of our Lord
Inrolled the Twenty-sixth day of May, One thousand eight hundred
and eight.