IMPROVEMENTS IN PORTABLE STEAM ENGINES
Year: 1854

page_text: LETTERS PATENT to Oliver Maggs, of Bourton, in the County of Dorset,
Iron founder, for the Invention of "IMPROVEMENTS IN PORTABLE STEAM
ENGINES."
Sealed the 27th April 1855, and dated the 30th October 1854.
PROVISIONAL SPECIFICATION left by the said Oliver Maggs at the
Office of the Commissioners of Patents, with his Petition, on the
30th October 1854.
I, OLIVER MAGGS, of Bourton, in the County of Dorset, Ironfounder,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
PORTABLE STEAM ENGINES" to be as follows:-
The first part of these improvements has reference to the boilers of portable
engines, and consists, firstly, in a novel configuration of the flues thereof, and
mode of arranging the same within the boiler, and is designed for the purpose
of strengthening the boiler, and obtaining a greater amount of heating surface
in'a given space than heretofore.
Secondly, in the use and application of a tube or tubes, generators or water
vessels, or other enclosed water spaces, to the centre or other part of the fire
box, the upper end or ends of such said tubes or other water spaces being
attached to the top or crown of the fire box, and the lower ends of such

page_text: tubes or other water spaces being also attached to any other desired part of
the fire box.
Thirdly, in the use and application to the boilers of portable engines, of
hollow trusses or arches, for the purpose of strengthening the top of the fire
box by these means, instead of by the solid stop heretofore employed for that
purpose, and at the same time increasing the amount of heating surface.
The second part of these improvements has reference to the working parts
of portable steam engines, and consists, firstly, in placing the cylinder and
feed pump in the chimney instead of outside the boiler, as commonly practised,
said chimney. being situated immediately over the said-fire box; and it is
proposed to place the valves of the said pump on the outside of the chimney,
for convenience of access to such parts, and by these meaus to prevent
condensation of the steam within the cylinder, and loss of heat by radiation.
Secondly, in the use and employment of two fly wheels or an additional fly
wheel in the construction of portable steam engines of the same or different
diameters, instead of only one fly wheel, as commonly practised, for the purpose
of distributing the weight more uniformly, by placing a fly wheel at each side
of the boiler, instead of at one side only, as hitherto practised.
Thirdly, in the use of a new mechanical contrivance for adjusting the move-
ment of the steam slide, by employing for that purpose a lever, the upper
end of which is affixed to the steam slide, and the lower end passes through
a hole in the eccentric rod, so that, according as such rod is adjusted either
upwards or downwards upon the aforesaid lever, in like manner the move-
ment of the steam slide will be greater or less, so as to cut off the steam
at any desired part of the piston's stroke, and thus afford a ready and simple
means of adjusting the amount of steam employed to the nature of the work
required.
The fourth and last part of these improvements consists in so connecting the
working cylinder with the upper part of the boiler as that it forms a portion
thereof, the purpose being to maintain the steam which is. in the cylinder at
the same temperature, or nearly so, as the steam in the boiler, and thus to
prevent loss of power by the radiation of heat consequent upon placing the
cylinder distinct and separate from the boiler, or only slightly connecting it
thereto, as commonly practised.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Oliver Maggs in the Great Seal Patent Office on the
30th April 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, OLIVER
MAGGS, of Bourton, in the County of Dorset, Ironfounder, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of October, in the year of our Lord
One thousand eight hundred and fifty-four, in the eighteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Oliver Maggs, Her special licence that I, the said Oliver Maggs, my
executors, administrators, and assigns, or such others as I, the said Oliver
Maggs, my 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, an Invention for "IMPROVEMENTS IN PORTABLE STEAM
ENGINES," upon the condition (amongst others) that I, the said Oliver
Maggs, by an instrument in writing under my hand and seal, should par-
ticularly 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 and immediately
after, the date of the said Letters Patent.
NOW KNOW YE, that I, the said Oliver Maggs, do hereby declare the
nature of the said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement
thereof (that is to say):-
My improvements are divided into three parts. The first part has reference
to the boilers of portable steam engines, and consists, firstly, in a novel
configuration of the flues thereof and mode of arranging the same within the
boiler, and designed for the purpose of strengthening the boiler, and obtaining
a greater amount of heating surface in a given space than heretofore.
Secondly, in the use of and application to the centre or other part of the
fire box of a.tube or tubes, generators or water vessels, or other enclosed
water spaces or chambers, the upper ends whereof are attached to the top or
crown of the fire box, and the lower ends to any other desired part of
said box.
Thirdly, in the use of and application to the boilers of portable engines of
hollow trusses or arches, for the purpose of strengthening the top of the fire

page_text: box by these means, instead of by the use of solid stays, as heretofore
practised, in the construction of boilers; and these improvements are alike
applicable to marine and other boilers.
The second part of my said improvements has reference to the working
parts of portable steam engines, and consists, firstly, in placing the cylinder
and feed pump inside the chimney instead of outside the boiler, as commonly
practised, said chimney being situated immediately over the said fire box; and
I propose to place the valves of the pump on the outside of the chimney, for
convenience of access to such parts, and by these means to prevent condensa-
tion of the steam within the cylinder, and loss of heat by radiation.
Secondly, in the use and employment of two fly wheels or an additional fly.
wheel in the construction of portable steam engines of the same or different
diameters instead of only one fly wheel, as commonly practised, for the purpose
of distributing the weight more uniformly, by placing a fly wheel at each side
of the boiler, instead of at one side only, as hitherto practised.
The third part of my said improvements consists in the use and employment
of a new mechanical contrivance for adjusting the movement of the steam
slide, so as to afford more ready and simple means than heretofore practised
of reducing the steam passages, thus enabling the engine to be worked below
the nominal power, and for effecting a saving of fuel.
The fourth and last part of my said improvements consists in so connecting
the working cylinder with the upper part of the boiler as that it forms a
portion thereof, for the purpose of maintaining the steam which is in the
cylinder at the same temperature, or nearly so, as the steam in the boiler, and
thus to prevent loss of power by radiation of the heat, consequent upon placing
the cylinder distinct and separate from the boiler, or only slightly connecting it
thereto, as commonly practised; and also in the general arrangements of the
engine and boiler, as above stated and represented by the Drawings.
In order to explain my said improvements as completely as possible, I now
proceed to describe the best means I am acquainted with for carrying the
same into practical effect, reference being had to the illustrative Drawings
annexed to these presents, and to the numeral figures and letters of reference
marked thereon respectively, as follows:-
DESCRIPTION OF THE DRAWINGS.
.At Sheet 1, Figure 1 is a longitudinal and vertical section of a portable boiler
(taken through about the centre thereof); Figure 2 is a transverse and vertical
section through the line A, B, at Figure 1. Figure 3 is a transverse and

page_text: detached views, in transverse section, of several new forms of flues, hercin-after
particularly described and referred to. At Sheet 2, Figure 8 is a side eleva-
tion of a portable steam engine constructed according to my improved method,
with the cylinder and feed pump in the chimney or smoke box of the boiler.
Figure 9 is an end elevation of the fire box end of the above-mentioned boiler.
At Sheet 3, Figure 10 is a longitudinal and vertical section of the portable
steam boiler exhibited at Sheet 2. Figure 11 is a transverse and vertical
section of said boiler through the line E, F, at Figure 11. At Sheet 4,
Figure 12 is a side elevation of a portable engine constructed according to my
improved method, with the cylinder connected to, and forming part of, the fire-
box end of the boiler. Figure 13 is an end elevation of this end of the boiler.
At Sheet 3, Figure 14 is a longitudinal and vertical section of the portable
steam boiler exhibited at Sheet 4. Figure 15 is a transverse and vertical
section of said boiler through the line G, H, at Figure 14 of said Sheet of
Drawings.
At each of the foregoing Figures of each Sheet of Drawings I employ
similar letters of reference to denote corresponding parts, in so far as such
parts appear or can be seen at each of the said Figures respectively. At
Sheet 1, A is the boiler; B, the fire box; C', C, horizontal flues connected
together by the vertical flue D; E, E, are water spaces or chambers, the
upper parts whereof are formed open, and with a flange, for connecting them
to the crown 6 of the fire box B. To the lower part of the pieces E, E, short
pipes F are connected, as also to the inner case B' of the fire box B, at any
convenient part thereof, for the purpose of allowing the water in the boiler to
circulate freely through said water chambers. By these means I expose a
larger amount of heating surface to the action of the fire, and at the same
time strengthen the top of the fire box. Another mode of strengthening the
top of the fire box, according to my said Invention, consists in securely con-
necting thereto, by rivets or otherwise, hollow trusses G, as shewn at Figure 3,
in lieu of the solid stop or stay now in use for that purpose. The above hollow
trusses may be connected either to the inside of the fire box, as exhibited, or
to the outside thereof, as denoted by the red lines; in either case, by this mode
of strengthening the top of the fire box, the amount of heating surface exposed
is also considerably augmented. It will be seen, upon referring to Figure 1,
that the upper flue C', which is situated above the crown of the fire box and
within the boiler, terminates in a smoked chamber or box H; to the upper
part of which, branch pipes I, I, are securely fixed by flanches; said pipes
terminating in another smoke box or case K, securely fixed to the top of the
boiler, and in which said box the feed pump (not shewn by the Drawing) and

page_text: cylinder L of the engine with its accessories are securely fixed; and, finally, to
the top of the smoke box K the chimney M is affixed.
I would remark, that
for convenience of access for repairing or inspecting the valves of the feed
pump I. propose placing them outside of the smoke box K, as exhibited at
Figure 9 of Sheet 2. h is a plate covering an opening i, for affording access
to the smoke chamber Hand flue C. In constructing boilers without the
chambers E, shewn at Sheet 1, I then place the smoke chamber H over the
centre of the crown of the fire box, as exhibited at Figure 10 of Sheet 3. By
the above improved mode of arranging and disposing the flues C, the smoke
box K and water chambers E, a much larger amount of heating: surface is
exposed and surrounded by the water in the boiler than heretofore; and by
placing the cylinder I and feed pump within the smoke box, the temperature
of the steam therein is maintained nearly uniform, and consequently the loss of
heat by radiation is thus prevented, as also the condensation of the steam
in the cylinder, as is the case where the cylinder is exposed to the atmosphere,
as heretofore commonly practised in the construction of portable engines. In
cases where it is required to expose a larger amount of surface of the flues
than that before described, the same may be effected by constructing the
flues of either of the forms exhibited at Figures 4, 5, 6, 7; but for general
purposes I prefer the form of flues exhibited at Figures 3 and 7, as being less
costly than the others. "
1
And as regards that part of my 'said improvements which has reference to
the working parts of portable steam engines, it is as follows:-With respect
to my improved mode of adjusting the movement of the slidė valve of the
cylinder, I employ for that purpose the mechanical arrangement exhibited at
Figure 1 of Sheet 1, and Figures 8 and 12 of Sheets 2 and 4, where a is a
lever, the fulcrum whereof is a pin at b, passed through a stud c, fixed into
the cylinder lid; the upper end of the lever a is connected to the rod d of the
slide valve, and over the lower part of the said lever a hole formed in the end
of the excentric rod e is passed, and thus connects them together, said rod
being securely fixed upon any desired part of the lever a by means of a
tightening screw f (as shewn); thus it will appear evident that the rod e may
be readily adjusted higher or lower on the lever a, and thus alter the amount
of movement of the slide valve, so as to reduce the steam passages or ports,
and thus enable the engine to be worked below the nominal power; thus
effecting a saving of steam, and consequently a corresponding saving of fuel.
At Sheets 2 and 4, O, O, are the fly wheels of the engine, keyed upon
opposite ends of the driving shaft P, and thus distributing the weight more
uniformly than by the use of one fly wheel only, as commonly practised; and

page_text: further, instead of placing the cylinder L within the smoke box, as before
described with reference to Sheet 1, I propose in some cases imbedding the
lower diameter of the cylinder L of the engine in the upper part of the boiler
at the fire box end thereof, and enclose the upper part of the cylinder in. a
case Q, as at Sheet 4, and if necessary the feed pump, as before stated; and
instead of placing the chimney over the cylinder as before, I place it at the
opposite end of the boiler, and connect the flues C, C', therewith, as exhibited
at Figures 12 and 14 of Sheets 3 and 4. In all other respects the working
parts of the engines, for admitting and emitting the steam to and from the
cylinder and transmitting the power, are the same as those usually employed
in portable steam engines.
Having now described the nature and object of my Invention of "Improve-
ments in Portable Steam Engines," and in what manner the same is to be
and may be performed, I would remark, in conclusion, that I do not claim
the exclusive use of any of the separate parts above mentioned and referred to,
except in so far as the same may be employed in combination and for the
purposes my said Invention; but what I claim is, the general arrangements
as represented by the several Sheets of Drawings hereunto annexed, and
above particularly described and referred to.
of
In witness whereof, I, the said Oliver Maggs, have hereunto set my.
hand and seal, this Thirtieth day of April, in the year of our Lord
One thousand eight hundred and fifty-five.
Witness,
ALEX. PRINCE,
4, Trafalgar Square.
OLIVER MAGGS. (L.S.)