CERTAIN IMPROVEMENTS ON STEAM ENGINES
Year: 1818

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MALAM, of Marsham Street, Westminster, in the County of Middlesex,
Engineer, send greeting.
WHEREAS His most Excellent Majesty King George the Third, by His
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Fifth day of August, in the fifty-eight year of His reign, did,
for Himself, His heirs and successors, give and grant unto me, the said John
Malam, His especial licence, that I, the said John Malam, my exors, adñiors,
and assigns, or such others as I, the said John Malam, my exors, adñiors,
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 law-
fully might make, use, exercise, and vend, within England, Wales, and the
Town of Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS ON
STEAM ENGINES;" in which said Letters Patent there is contained a proviso
obliging me, the said John Malam, 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 His Majesty's High Court of Chancery, within six
calendar months next and 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
John Malam, do hereby declare that the nature of my said Invention, and in

page_text: the manner in which the same is to be performed, are described and ascer-
tained in the plan annexed to these presents, and the following explanation
thereof, that is to say:-
My improvements in steam engines consist in making, arranging, and com-
bining the parts thereof, as in these presents hereafter described, in such a manner
as to effect a complete rotative engine, either with or without a piston, and having
no beam or crank between the said engine and the machinery which it may be
intended to drive. My said improved engine or engines. is not fitted with a fly
wheel, by which arrangement much room, and expence is saved in their con-
struction, in comparison with engines constructed in the former systems, which
require the aid of a heavy fly wheel, and an enormous beam, with cranks and
hand gear, by my improvements rendered altogether useless. These improve-
ments are such as allow the filling and discharging of the engine with steam in
a superior manner, and of employing it to the best advantage, for in it the
steam is uniformly acting, which is not the case in the beam engines hereto-
fore used, for in them both steam and time is lost during the change of
stroke. My improvements differing most essentially from the kind of engine
just mentioned, I am now to state how they differ from the rotative steam engines
heretofore invented. In these piston or pistons have in some cases been made
to revolve round a centre or round a drum, with a variety of ingenious contri-
vances to keep the vacuum and steam apart. In two or three cases alternately
revolving pistons have been used, others have partaken of the rectilineal and
rotative motions, and another having the outer ring stationary, whilst the inner
one attached to the axis run round within it, but in my improvements where
I use the pistons, such pistons, after the steam is turned on, continually
occupy by its gravity a position as described in Figures 1 and 3 in the Draw-
ing, whilst the hollow ring revolves round or upon its axis, and as this piston is
made of lead or other suitable metal, and fitted with the packing as in these
presents hereafter described, so as to be perfectly air-tight with the interior part
of the said hollow ring, which is turned out with the most scrupulous accuracy.
The steam on coming into the hollow ring from the axis, through the respective
arms, is always acting between the said piston and the receding lever valve or
slide plate, whilst the division which is then discharging to the condensor pro-
duces a vacuum, to increase the action and power of the engine. In the use
of my improvements the necessity of having safety valves for securing the
boiler from accidents is avoided, the engine being so constructed, by a combina-
tion between its diameter and the weight of the piston, as to act to a certain
power, and should that power be increased the steam will pass through the
engine without injury to the boiler or impeding the action of the engine itself.

page_text: 'here
But as I have now only adverfed to these iniprovements, which are carried into
effect by employing a piston which fits air-tight within the hollow ring, I am
now to mention another species of improvement, where I make a complete
rotative engine.without using either a piston; slide, or valve of any descrip-
tion, and this species of rotative engine' is particularly adapted to smaller
powers, if constructed so as to be used with water, and of very large powers if
fusible metal, such as lead, 'tin, bismuth, or mixtures of these metals are.em-
ployed. As the two Figures 5 and 6 in the margin exhibit this species of
improvement in steam engines, which on referring to them are herein particularly
described, it is unnecessary to say much more of them in this place. I am
only observe that at whatever pressure this species of engine is intended.to
work, to such height must the column of water or metal in fusion therein em-
ployed be carried in the hollow rim. To prevent the condensation of the steam
when it first enters the respective divisions of the hollow rim, the flue of the
boiler is carried, round it between the outer case of the engine and its jacket,
by this contrivance so lieating the water employed as to add vigour, to the
steam, and for keeping the metals in fusion, when such are employed in lieu of
water. In addition to which, in the latter case, in some instances à fire should
be introduced beneath the engine, to act through the flue between the jacket
and its outer case just alluded to: The application of the expansive force of
steam, and the power obtained by its condensation, are not new; nor do I
attempt any innovation upon established principles, my claim resting solely upon
the peculiar manner of making, arranging and combining the parts hereafter.
mentioned, so as to form and make, and which I have formed and
made, a complete, simple, and effective engine or engines, by which the
power obtained from steam, both by expansion and condensation; is com-
municated to machinery, &c., at a comparatively small expence and with
some advantages in the saving of fuel. In the annexed Drawing, Figures 1
and 2, which are different sections of the same improvements in steam engines,
have the corresponding. parts marked with like letters for the sake of clear-
ness. A is the steam pipe which conveys the steam from the boiler through
ts exit flue underground through the cistern B into the hollow standard C 1;
on this standard, that is to say, C 1 and C2, and on one similar thereto at the
opposite side of the hollow ring, as shewn in Figure 2, C3, C4, the axis of,
hat hollow ring is supported. D is a fixed axle made of brass or other metal,
which is divided by a plate of the same metal through its centre into two parts,
narked 1 and 2, Figure 1. Into that part which is marked 1 the steam is
dmitted by the opening L, Figure 2, and from it passes to the respective divi-
ions of the hollow ring F 1, F 2, F3, in the division between the lever plates or

page_text: valves K 1, K 2, K 3, and the piston G, which, when the engine is in action,
always occupies by its gravity a situation similar to that described in Figure 1.
The arms E 1, E2, E 3, being hollow, permit a communication from the fixed
axle at M, Fig. 2, to the hollow ring. This engine is so constructed that the
standard communicating with that division of the fixed axle which supplies the
engine with steam is connected with the boiler, and that when the division in
action is in use to supply it, whilst the opposite division, marked 2 in Figure 1,
is connected with the condensing vessel, so that whilst one division is receiving
the steain for propelling the engine round upon its axis by its expansive force,
employed between the piston and the receding lever plate or valve, the next
superior division is emptied of the steam it had contained by a similar opening
in the partition of the fixed axle 2, through the standard of support, C 2, and a
vacuum is thereby struck. The inside of the hollow ring is turned with
truth and exactness, so that when in action the piston G, by means of the
metallic packing, as expressed in Figure 1 at H, may in all positions of the
hollow ring be perfectly steam tight. The piston is also fitted with the guide
wheels I 1, I 2. The lever plates or valves turn upon centres and fall into
recesses in the inner ring, when it is necessary they should pass the piston,
and they are ground and faced so as to fit when in action so truly to the
inside of the hollow ring as not to allow any portion of the steam to pass them.
Upon the fixed axle D is fitted the hollow axis N, Figure 2, to which is fixed
the arms and hollow ring, all being together supported upon the standards by
proper brasses. The hollow axis N, Figure 2, must be produced or made of
such length as to admit of mill-work being coupled or attached to it.
great
Figures 3 and 4 are sections of a second species of improvement of steam
As in
engines, the corresponding parts being marked with the same letters.
this improvement in steam engines the steam is conveyed towards the axis
though the cistern and the hollow standards, and from thence enters the hollow
ring by openings or slits in the axis which come in contact with the openings
in the supplying hollow standard as the engine revolves, and as it is furnished
with a piston similar to that described in Figure 1, with brass expanding
packing, and as the inside of the said hollow ring is turned with the greatest
nicety, as in the former case, it is not necessary to describe these parts again,
but merely to describe these which are different therefrom, and these are, first,
the axis A, Figures 3 and 4, which is moveable with the hollow ring and
thereunto fixed. This axis is hollow, and divided into three equal partitions
through the whole length of its hollow part, which extends from that end
where the steam is allowed to enter into to somewhat beyond the arms leading
to the hollow ring. Each of these partitions in the a axis has two openings

page_text: or slits in a right line with each other, the one is connected to its adjoining
arm the other falls over the opening in the hollow standard. Their uses are
to allow the steam to enter in the hollow ring, and there to exert its force
between the piston and the receding slide plate or valve, and afterwards, when
the openings over the hollow standford approximate with that part of the said
standard leading to the condensor, there to discharge the steam, and to strike
the vacuum. Iustead of being fitted with the lever plates as shewn in
Figure 1, there is a race attached between the standard of support and the
engine, into which the triggers marked in red lines run, these being attached
to the working gear C, C, Figure 3 and 4, at the proper times, drawn in the
plates B, which slide in grooves and fit therein perfectly air-tight, and again
when it is necessary thrust them out. This operation is effected by a pinion
attached to the lever C, and works in the racks cast on the slides and on the
doors of the arms for that purpose.
Figure 5 and 6 are sections of a third species of improvement in steam en-
gines, having, for the sake of perspecuity, the corresponding parts of each section
marked with like letters. A is the steam pipe which admits steam into the
steam chamber B. The steam being received into the chamber passes from
thence into the compartments of the cylinder or drum C 1, C 2, C3, C4, by
means of the steam ways F 1, F 2, F 3, F 4. These steamways are shutt off
from the steam chamber B in succession as the engine revolves, by being im-
mersed in the fluid or metal in fuseion, according as one or the other is used
where it expansive force is exerted between the partitional divisions and the
surface of the water Y, Y, or metal in fuscion employed for forming a joint and
gives the engine a rotatory motion, from thence by the openings in the outer ring
01, 02, 03, 0 4, of the internal cylinder or drum it is allowed to escape into
the case G, from whence by the pipe W, attached thereto, it is conveyed to the
cistern and there condensed, and the vacuum formed in the compartment then
discharged. The cylinder or drum is supported on one side by the immoveable
steam pipe A, and on the other by the solid axis D, which projects beyond
In each case the
the case sufficiently to allow mill-work to be coupled to it.
loss of steam and the fusible metal or fluid employed from the drum of the
engine is prevented by the metallic packing E, E. II is the jacket to the
case of the engine at a sufficient distance therefrom to act as a fluid round it
from the flue of the engine boiler, the entrance thereto being at I, and the
exit therefrom at K; L, L, a feed pipe fixed to the steam pipe A, for the purpose
of allowing the fusible metal or fluid used to return towards that part of the
engine which when in action occupiers for the time being the lowermost
situation; M, the iron plate for supporting the whole apparatus, which is bolted

page_text: down to the foundat". N, N, N; N, are feed pipes to the respective com-
partments C 1, C2, C3, and C 4, for the purpose of conveying-the fluid or
metal infusion into them as such descends to supply the place lately occupied
by the steam. More forms or shapes of my Invention might be given, but these
already described are so simple and easily understood and executed by. an
engineer or mechanist as to render further explanations unnecessary; on this
account I have omitted describing the air pump, which is the same as that
used in other engines, and worked by gear attached to the axis in my im-
provement: I have also deemed it unnecessary to give a particular description of
the boiler, conceiving it to be a thing which every engine maker is acquainted
with. Let it suffice to say that I use such boilers, air pumps, and condensors
as are common to other steam engines. It may be proper to observe my engine
works with or without the air pump. In small ones it may be dispensed with
but in large powers it becomes necessary.
In witness whereof, I, the said John Malam, have hereunto set my. hand
and seal, the Fourth day of February, in the year of our Lord One