IMPROVEMENTS IN MARINE STEAM ENGINES
Year: 1854

page_text: LETTERS PATENT to John Elder, of Glasgow, in the County of Lanark,
Engineer, for the Invention of "IMPROVEMENTS IN MARINE STEAM ENGINES."
Sealed the 25th April 1854, and dated the 25th February 1854.
PROVISIONAL SPECIFICATION left. by the said John Elder at the Office
of the Commissioners of Patents, with his Petition, on the 25th February
1854.
I, JOHN ELDER, of Glasgow, in the County of Lanark, Engineer, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN MARINE STEAM
ENGINES" to be as follows:-
My Invention consists in making such a constructive disposition of the
essential parts of horizontal direct action condensing marine engines for screw
steamers as to secure greater compactness of arrangement and simplicity of
action of the moving parts than are obtained by any form or construction
heretofore practised. And this I effect by placing the steam cylinder of the
engine or both steam cylinders of a pair of such engines on one side of the
screw shaft, and the air pumps and condensers on the other side, as commonly
practised; but my improvement essentially consists in employing two or more
air pumps for each engine, and disposing them sufficiently far apart in lines

page_text: parallel, and on each side of the axis of their respective steam cylinders to
permit the connection rods, guide blocks, and cross head frame to pass between
them, and to be supported by them. The arrangement I prefer is to employ
four rods for each steam piston, and to connect them in a suitable cross head
frame beyond which the rods are prolonged, so as that the lower pair, one on
each side, serve as the air-pump rods, and the upper pair serve the like purpose
for the feed and bilge pumps. But this arrangement or distribution of those
pumps may be different and varied at pleasure, in so far as that the upper
piston rod on one side, and the lower one on the other side, may become the
air-pump rods, and the other diagonal pair will then serve for the feed and
bilge pumps.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Elder in the Great Seal Patent Office on the 24th
August 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
ELDER, of Glasgow, in the County of Lanark, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fifth day of February, in the year of our Lord
One thousand eight hundred and fifty-four, in the seventeenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Elder, Her special licence that I, the said John Elder,
my executors, administrators, and assigns, or such others as I, the said
John Elder, 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, exer-
cise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN MARINE STEAM ENGINES," upon the condition (amongst others) that I, the
said John Elder, by an instrument in writing under my hand and seal, 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 and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Elder, do hereby declare
the nature of the said Invention, and in what manner the same is to be

page_text: performed, to be particularly described and ascertained in and by the following
statement thereof (that is to say) :-
My Invention consists in making such a constructive disposition of the
essential parts of horizontal direct action condensing marine engines for
screw steamers as to secure greater compactness of arrangement and sim-
plicity of action of the moving parts than are obtained by any form or construc-
tion heretofore practised. And this I effect by placing the steam cylinder
of the engine, or both steam cylinders of a pair of such engines, on one side of
the screw shaft, and the air pumps and condenser on the other side, as
commonly practised; but my improvement essentially consists in employing
two or more air pumps for each engine, and disposing them sufficiently far
apart in lines parallel and on each side of the axis of their respective steam
cylinders to permit the connection rods, guide blocks, and cross head frame to
pass between them and to be supported by them. The arrangement I prefer
is to employ four rods for each steam piston, and to connect them in a suitable
cross head frame, beyond which the rods are prolonged, so as that the lower
pair, one on each side, serve as the air-pump rods, and the upper pair serve
the like purpose for the feed and bilge pumps. But this arrangement or distri-
bution of those pumps may be different and varied at pleasure in so far as that
the upper piston rod on one side, and the lower one on the other side, may
become the air-pump rods, and the other diagonal pair will then serve for the.
feed and bilge pumps.
Having thus stated the nature of my Invention, I will proceed to describe
the best means I am acquainted with for performing the same.
Figure 1
DESCRIPTION OF THE DRAWINGS.
longitudinal section through one of the engines, Figure-
front view of the cylinder and plummer blocks and cross section of the con-
denser, taken through the valves; and Figure 3 is a half plan and section of one
of the engines. The same parts are denoted by the same letters in these and
the other Figures.
These Drawings refer to a pair of horizontal direct acting engines, coupled
at right angles as usual, and furnished with ordinary long D valves actuated
by such a link motion as that commonly employed in locomotive railway
engines, and controllable by the engineer, on a starting platform between the
condensers by means of suitable reversing gear. The pistons in this example
are seventy-two inches diameter and three feet stroke. They are fitted with
front view of the cylinder and plummer blocks and cross section of the con-
denser, taken through the valves; and Figure 3 is a half plan and section of one
of the engines. The same parts are denoted by the same letters in these and
the other Figures.
These Drawings refer to a pair of horizontal direct acting engines, coupled
at right angles as usual, and furnished with ordinary long D valves actuated
by such a link motion as that commonly employed in locomotive railway
engines, and controllable by the engineer, on a starting platform between the
condensers by means of suitable reversing gear. The pistons in this example
are seventy-two inches diameter and three feet stroke. They are fitted with

page_text: 9,
spring packings in the ordinary way, but have broad flanges cast on the junk
rings to lessen the wearing of the cylinders as much as possible. The
cylinders are formed with check recesses c (of about half an inch) at each end
to allow of any dirt or grit to accumulate in them without detriment to the
pistons, and which matters may be removed from time to time. The pistons
are each furnished with four piston rods d passing through stuffing boxes cast
on the front of the cylinder, and they are made fast by cutters e in malleable
iron sockets f. Into these sockets are also cuttered the rods which extend
in continuation of the four piston rods d to the feed and bilge pumps h and i,
(of which the two upper rods are the plungers,) and to the air pumps j, j, of
which there are two to each steam cylinder. On the sockets f, two side rods k
are made fast by means of nuts I screwed on the ends of the sockets passing
through the cross tails of the side rods k, and the extremities of these rods are
again made fast by means of nuts into the cross heads m, which are made to
work in cast-iron sliding blocks n, fitted by boring in suitable parallel ways
formed in the cheeks of the condenser. This cross head m carries one end of
the connecting rod o, by which the action of the piston is transferred to the
crank a of the propeller shaft in the ordinary manner. This shaft is carried in
the plummer blocks p, which are cast hollow and in one piece, and thus serve
to bind the cylinders and condensers together by means of the bolts 2. This
end is further secured by a strong cast-iron exhaust pipe » extending between
the valve casing and condenser. The plummer blocks p also carry the weigh
or rocking shafts for transmitting motion from the link t to the steam
valve.
To illustrate the action of the engines (of which the novelty mainly consists
in the arrangement of the pumps and condenser) let it be assumed that the
steam which has done duty in the cylinder escapes by either port into the
exhaust pipe communicating with the condenser ut, and that being condensed
by the injection water from the pipe v, it falls down by the two central
passages w, shown more fully in the Sheet of Sections, Figures 4 to 9 inclusive.
The hot water then fills the spaces below the foot valves a, through which it is
drawn on the recession of the air-pump plunger and fills the air-pump barrel,
when by the succeeding stroke it is forced through the delivery valves y into
the passages, from which it is delivered through the ship's side by means of
the discharge pipe a'. By this arrangement a higher vacuum is produced than
is commonly attained, in consequence of the water having to rise only a very
small distance to enter the pump, for in the passages from the condenser it
must always stand about the level of the foot valves, and no air can enter the

page_text: pump. The action is adjusted by making the spaces between the foot and
discharge valves each equal to the capacity of the pump barrel.
Having now described the nature of my Invention and the best way I am
acquainted with of performing the same, I would wish it to be understood that
I do not confine myself to the details shown, so long as the peculiar character
of my Invention is retained. But what I claim is, the special combination and
arrangement herein-before described.
In witness whereof, I, the said John Elder, have hereunto set my
hand and seal, this Twenty-first day of August, in the year of our
Lord One thousand eight hundred and fifty-four.
Witness,
RICH S. CUNliff,
of Glasgow.
JOHN ELDER. (L.S.)