IMPROVEMENTS IN GENERATING STEAM
Year: 1852

page_text: LETTERS PATENT to Thomas Lawes, of 32, City Road, St. Luke's,
County of Middlesex, for the Invention of "IMPROVEMENTS IN
GENERATING STEAM."
Sealed the 30th March 1853, and dated the 1st October 1852.
PROVISIONAL SPECIFICATION left by the said Thomas Lawes at
the Office of the Commissioners of Patents, with his Petition,
on the 1st October 1852.
I, THOMAS LAWES, of 32, City Road, St. Luke's, in the County of
Middlesex, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN GENERATING STEAM" to be as follows, namely:-
To procure high pressure steam quickly and cheaply, by allowing a
large generating surface to come into close contact with a small body
of water. This object may be accomplished by a new description of
steam generator nade upon the principle described as under, together
with the Drawings hereto annexed.
Figures 1, 2, & 3, are isometrical perspective views of some of the

page_text: different forms in which the generators may be made, with the ends
removed to shew the principle on which are they constructed.
Figure 1. A, is the ash pit; B, the furnace, the sides and top being
formed of the tubes in which the steam is generated; C, C, the steam
chambers D, D, tubes containing part water and part steam, commu-
nicating with E, E, the supply water tubes; F, F, F, small generating
tubes, with plugs at ends for the purpose of cleaning the same; H, H,
communicating tubes to safety valves and engine; I, tube communi-
cating with force pump; G, G, small plugs removable for cleaning.
Figure 2. In this form of boiler the sides and top of furnace are
composed of double iron plates placed at a small distance from cach
other, and secured by numerous rivets, forming as it were a net-work
of rivets, between which the water circulates and steam is generated.
A, is the ash pit; B, is the furnace; C, C, C, the double iron plates;
D, D, the steam and water tubes communicating with C, C; E, the
steam chamber; F, small tubes communicating with C, C, and E;
G, G, iron plates removable for cleaning; H, tube communicating
with safety valve and engine; I, supply tube.
Figure 3. In this form the boiler or generator is composed of 2 large
iron plate tubes of different sizes sliding one within the other, and
secured together by bolts and flanges at each end (but which may be
removed to allow the inner tube to be drawn out for the purpose of
cleaning), leaving a space between them as shewn in fugure for the
water, the furnace being within the inner tube. A, is the ash pit;
B, the furnace; C, C, the inner and outer tubes; D, the steam
chamber; E, the steam and water tubes communicating with the
water between C, C, by the tubes G, G; F, tubes connecting D, with
C, C; II, tube to valves and engine; I, supply tube.
Boilers on this principle may be made in any form and size, and
either portable or not.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Lawes in the Great Seal Patent Office,
on the 1st April 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
Thomas Lawes, of 32, City Road, St. Luke's, in the County of
Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of October, in the year of
our Lord One thousand eight hundred and fifty-two, in the sixteenth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Thomás Lawes, Her special licence that I,
the said Thomas Lawes, my executors, administrators, and assigns, or
such others as I, the said Thomas Laws, executors, administrators,
and assigns, should at any time agree with, and no others, from time to
time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, and Hir* Majesty's Colonies, an Invention for
"IMPROVEMENTS IN GENERATING STEAM," upon the condition (amongst
others) that I, the said Thomas Lawes, by an instrument in writing
under my hand and scal, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to be
performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas Lawes, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the Sheet of
Drawings hereunto annexed, and to the figures & letters of reference
marked thereon (that is to say):
My Invention of improvements in generating steam have for their
object to expose a large area of heating surface within a small compass,

page_text: and in comparison to the quantity of water acted upon, also to afford
facilities for cleaning out boilers.
To generate high pressure steam quickly and cheaply I expose a
large amount of flue and fire surface, which is in close contact with
only a small body of water, this object may be accomplished by either
of the several arrangements of steam generating apparatus herein-after
described and illustrated by the Drawings hereto annexed..
Figures 1, 2, and 3, are isometrical perspective views of some of the
different forms in which the generators may be made, with the ends re-
moved to shew the principle on which they are constructed.
Figure 1, represents an arrangement in which the heating surface
is formed principally of tubes. A, is the ash pit; B, the furnace, the
sides and top being formed of the tubes in which the steam is generated;
C, C, the steam chambers; D, D, tubes containing part water and
part steam, communicating with E, E, the supply water tubes; F, F,
small generating tubes, with plugs at ends for the purpose of cleaning
the same; G, G, plugs; H, H, communicating tubes to safety valves
and engine; I, tube communicating with force pump; L, L, horizontal
tubes with plugs M, M, removable for cleaning; J, tube connecting
C, C, with D, D. The whole is to be enclosed by brickwork so
arranged that the heat and flame circulates around the entire surface
below the water level.
This generator is an improvenient on the same principle for which
I obtained Letters Patent on or about the Fourth January, One
thousand eight hundred and fifty-one.
Figure 2, represents a boiler of a somewhat similar arrangement,
but in which flat surfaces are exposed instead of tubes. In this
form of boiler the sides and top of furnace are composed of double
iron plates placed at a small distance from each other, and secured
by numerous rivets, as represented, between which plates the water
circulates and steam is generated. A, is the ash pit; B, is the
furnace; C, C, C, the double iron plates; D, D, the steam and water
tubes communicating with C, C; E, the steam chamber; F, small
tubes communicating with C, C, and E.; G, G, iron plates. removable

page_text: for cleaning.; H, tube communicating with safety valve and engine;
I, supply tube; J, J, small tubes connecting D, D, and C, C; and
K, K, small steam communication between E, and D.
Figure 3, represents my improvements adapted to the Cornish boiler,
in which a thin film of water is exposed to the action of the
fire, whereby the generation of steam is facilitated and economized.
In this form the boiler or generator is composed of two large
cylinders of different sizes placed concentric one within the other, and
secured together by bolts and flanges at each end, leaving a space
between them, as shewn in Drawing for the water. The furnace is
within the inner tube, which is open throughout. A, is the ash pit;
B, the furnace; C, C, the inner cylinder; D, D, the outer cylinder;
E, the steam chamber; F, F, the reserve water tubes (two thirds filled
with water); G, G, tubes connecting E, with F, F; H, tube to valves
and engine; I, supply tube from pump; J, tubes connecting D, D,
with F, F; K, K, space for water between inner and outer tubes C, C,
and D, D.
Figure 4, shews a front elevation of Figure 3. L, flange on each
end of inner and outer tubes for bolting together. P, P, pulleys
fastened to outer side tube C, C, to run it in and out when required
to be cleaned.
The connection of the steam chamber E, with outer cylinder D, is
made by openings cut in the plate, and then E, is rivetted on so as to
form one solid connection, or I connect the two parts by small tubes,
which is equally good, and either of which plans I propose to use as
circumstances may require.
The concentric cylinders forming the body of the boiler I form of
equal length; the inner one C, with internal flanges at either end,
and the outer cylinder D, with external flanges. I prefer to make
the external diameter of C, about two inches smaller than internal
diameter of D, so that when placed concentric a space of an inch
intervenes between the two. This contains the water immediately
acted on by the fire, from which steam is evolved rapidly, and passes up
into the steam chamber E. The small tubes G, G, maintain the
equilibrium of pressure in water chambers F, F, which reserve pro-

page_text: vides for any rapid decrease in D, D, and keeps up the required level.
The cylinders C, and D, are connected by annular plates at either
end, bolted to their several flanges before-mentioned.
The inner
cylinder C, is mounted on rollers P, P, which traverse rails or surfaces
on the inside of D. By this means the inner cylinder is easily
removed, and for which purpose I provide either a permanent or tem-
porary continuation of rails beyond the limits of the boiler to receive C,
when so withdrawn. To effect this operation it is simply necessary to
remove the end plates, when the inner cylinder may be drawn out.
The boiler can then be easily and properly cleaned or examined, and
returned to its position.
This boiler I enclose entirely in the brickwork, and form the flues
with a circulation embracing as much as possible of the external
surface of D, D, and also below the water level in chambers F, F.
:
The principal features in my improved generators are, First, the
exceedingly small quantity of water used, and the large surface exposed
to the action of the fire, and the consequent rapid and almost instanta-
neous generation of steam with the smallest possible expenditure of
fuel. Two this object is materially facilitated by the adoption of the
water tubes, which are placed at the sides of each generator, and which
being connected to it by small steam tubes only, they act as a reservoir
of water to the generator so heated as to save that condensation which
usually takes place where steam at a high pressure and water come in
contact. Third: in consequence of the easy manner in which the inner
tube can be removed for cleaning, as shown in Drawings three and
four, the space for water between the inner and outer tubes can be
reduced to the smallest possible compass, and thus the desired object
of an infinitesinial quantity of water being exposed to the largest heating
surface is obtained.
Boilers on this principle may be made in any form and size, and
either portable or otherwise.
Having described the nature of my Invention, and the manner of
performing the same, what I claim under the before in part recited
Letters is,--
First, the arrangements of boilers or steam generators represented

page_text: in the annexed Drawing, whereby a thin film or small body of water
is exposed to the action of the fire surface with a reserve of water
in a chamber or chambers in communication therewith, as herein-before
described.
Secondly, I claim withdrawing the internal cylinder of boiler,
Figures 3, and 4, for the purposes of cleaning, as herein-before de-
scribed, and the arrangements adopted for that purpose.
In witness whereof, I, the said Thomas Lawes, have hereunto set
my hand and seal, this First day of April, One thousand eight
hundred and fifty-three.
THOMAS LAWES. (L.S.)