IMPROVEMENTS IN MARINE ENGINES AND BOILERS AND THEIR APPURTENANCES
Year: 1858

page_text: LETTERS PATENT to Lavington Evans Fletcher, of Upper Norwood, in the
County of Surrey, for the Invention of "IMPROVEMENTS IN MARINE
ENGINES AND BOILERS AND THEIR APPURTENANCES."
Sealed the 17th September 1858, and dated the 18th March 1858.
PROVISIONAL SPECIFICATION left by the said Lavington Evans Fletcher
at the Office of the Commissioners of Patents, with his Petition, on the
18th March 1858.
I, LAVINGTON EVANS FLETCHER, of Upper Norwood, in the County of Surrey,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
MARINE ENGINES AND BOILERS, AND THEIR APPURTENANCES," to be as follows:-
The object of my Invention is to promote the economy and safety of steam
navigation by effecting a saving in the consumption of fuel, which has so
important an influence on the profitable working of steamers of all classes,
but more especially of those engaged in long ocean voyages, and by preventing
the inconvenience and danger that frequently arise to steam vessels from the
numerous openings which it is at present usual to make in them, both at and
below the water line for the various pipes for engines and boilers, &c., while
at the same time my Invention secures many incidental advantages, some of
which are as follows:-I reduce the weight of the engines and boilers, which
is of importance to steamers required to draw little water for the navigation of
077

page_text: shallows, in addition to which I am enabled to burn both smokelessly and
efficiently every description of coal, even the most highly bitumenous north
country coals, such as the Hartley's, &c., and at the same time I render the
engine and boiler room more comfortable and healthy by considerably reducing
their temperature, which is generally most inconveniently high, especially in
hot climates, while by the reduction of the amount of fuel necessary to be
carried for the consumption of the boilers, I am thereby able to add to the
available and remunerative space for passengers and cargo. I produce this
saving of fuel by a more economic generation of steam in the boiler in the
first place, and by utilizing the steam more fully in its expenditure in the
engine in the second place.
In the first place, the economic generation of steam in the boiler.-The
economic production of steam is principally dependent upon the perfect com-
bustion of the fuel which is at present extremely imperfect in marine boilers,
arising from the fact that the value of space on board a steamer limits the
size of the boiler, and thus a very heavy duty is imposed upon it, and more
especially upon the furnaces in which an amount of fuel quite unusual in
stationary engines has to be consumed per square foot of fire grate surface.
The thick fires consequent on this are too much for the natural draft produced
by a chimney, more especially by such chimneys as are admissible on board
ship; and the present draft, imperfect as it is, is only produced by a most
extravagant expenditure of heat in the chimney, which creates great incon-
venience by heating the smoke box doors, and thus raising the temperature
of the boiler room and engine room, much to the discomfort and injury to
the health of the engineers, especially in hot climates, as well as injuring
the base of the chimney, and even in some cases setting fire to the deck.
These thick fires obtain only an imperfect supply of air, the consequence
of which is, imperfect combustion, the formation of smoke, and waste of fuel.
I remedy these very serious defects by using mechanical means for stimulating
the draft, and thus I can obtain any amount that may be found necessary, and
secure a sufficient supply of air for perfect combustion, and the entire pre-
vention of smoke, even with thick fires and bituminous coals. Having this
command of the draft I am able to introduce arrangements which are here-
after more fully set forth, which have been hitherto inadmissible into, the
furnace for the more complete mixture and combustion of the gasses, and also
to introduce proportions into the boiler for the more complete absorption and
utilization of the heat resulting therefrom, and thus by retaining the heat in
the boiler instead of allowing it to escape into the smoke box, 1 prevent the
inconvenience previously mentioned, which is experienced at the smoke box

page_text: doors and base of chimney. In addition to utilizing more fully the fuel con-
sumed, I am also enabled by the application of the artificial draft to marine
boilers so to increase their evaporative power as to reduce their size, and
consequently their weight, from which many advantages arise. From the
diminution of the weight of the boiler, steamers may be built of lighter
draft of water, the advantage of which has already been alluded to, and
from the diminution in the size of the boilers, I am able to leave a space
all round them, so as to afford room for convenient access for examining
and repairing them, and I place therein a hot air chamber, so that the use
of any coating to prevent radiation of heat is unnecessary, and thus the
shell being uncovered is less liable to corrosion, and can the more
readily be examined; I am also able from the reduced size of the boilers
to place them in a more convenient position (hereafter more fully set forth)
than would be possible with boilers of the ordinary size, and also to effect
other neat and suitable arrangements of details conducive to the efficient
discharge of the engineer's duty, and to which I consequently attach im-
portance; and I am further able, from the reduced size of the boilers, to
make them stronger with the same or even with a less weight of metal, and
thus safely to use steam of a higher pressure, from which much economy will
result. And in order to promotestill further the economic generation of steam
in the boiler, I combine with the artificial draft a system of condensing by
cold surfaces instead of by injection, by which means I feed the boiler con-
stantly with distilled water instead of either with sea or river water as the case
may be, and thus save the waste of heat consequent on the frequent blowing
out, rendered necessary by the use of this sea or river water, and keep the
boiler free from deposit of any sort whatever. This enables me to reduce the
width of the water spaces, and thus to make another reduction in the size and
weight of the boiler in addition to that already explained. And my Invention
further provides a method for supplying or making up any waste of the
distilled water that may arise from leakage or blowing off from the safety
valves or any other cause, and which method I prefer to any of the numerous
plans that have been proposed for effecting this object. I consider surface
condensation a very important accessory to the artificial draft, and that without
it the full benefit of the artificial draft cannot be realized, since by the use of
distilled water in the boiler I am able to urge the fires to a much higher
intensity than would otherwise be at all prudent considering the boiler's
durability, and in addition to which, by combining the reductions made in the
weight of the boiler by each system separately, as already explained, I am
able so considerably to modify the proportions and shape of the boiler as to

page_text: introduce forms hitherto not used and inadmissable on board ship except
for engines of small power, and I can thus make use safely of steam of a
much higher pressure than has hitherto been at all practicable.
In the second place, arrangements for utilizing the steam more fully in its
expenditure in the engine.-Although the boiler may be adapted for supplying
high pressure steam, as just explained, still unless this steam is suitably used
in the engines its generation will prove comparatively fruitless, since the full
advantage of steam of any pressure cannot be realized without expansion, and
more especially that of high pressure steam, which requires to be expanded
considerably to develope its power fully. Very much of the advantage,
however, of working steam expansively is at present lost in marine engines
from the temperature of the cylinder not being sufficiently maintained, for in
addition to the loss of heat from external radiation, the expansive action of
the steam within the cylinder has such a cooling effect that the cylinder
becomes colder than the steam which enters it from the boiler, and thus from
the rapid conducting power of the metal of the cylinder there is set up within
it an action which has received too little attention, but which exercises a
highly injurious effect upon the economical expenditure of the steam.
This
action consists of an alternate condensation and evaporation, which takes
place upon the internal surface of the cylinder as well as the piston, and
which entails upon the boiler an extra and entirely unproductive amount
of evaporative duty, and on the condenser a corresponding amount of un-
necessary condensation; and this alternate condensation and evaporation can
only be arrested by maintaining the cylinder at a temperature at least as high
as that of saturated steam at the initial pressure, whether this be effected by
superheating the steam before entering the cylinder, or by applying heat
directly to the metal of the cylinder itself. The adoption of suitable means
for maintaining the temperature of the cylinder will, it is therefore clear,
have an important effect upon the system of surface condensation, since by
arresting the action of evaporation just alluded to, and thus saving a con-
siderable amount of useless duty otherwise imposed upon the condenser,
it follows that a smaller amount of cooling surface will suffice, and the first
cost and size of condenser be consequently reduced.
I have now stated generally the points relating to economy in marine
engines which my Invention affects, and will briefly recapitulate for greater
clearness-I effect a more rapid and complete combustion of the fuel, and
obtain a more perfect absorption and consequent utilization of the heat gene-
rated therefrom; I feed the boiler constantly with distilled water; I generate
steam at a higher pressure than has hitherto been usual, and more fully utilize

page_text: its expansive action; I thus considerably reduce the consumption of fuel, and
at the same time lower the inconvenient and unhealthy temperature of the
engine and boiler rooms, as well as reducing the weight of engines and boilers
and the size of coal bunkers. I effect this by the novel combination of three
systems,first, that of the artificial draft; second, that of condensation by cold
surfaces instead of by injection; and, thirdly, that of maintaining the cylinder
at a sufficiently high temperature to prevent condensation and evaporation
going on upon the internal surfaces. Without this entire combination the full
advantage of 'neither one of these systems can be realized. Full advantage
cannot be taken of the artificial draft for urging the fire to its greatest
intensity,nor can the boiler be reduced to its strongest forin for the generation
of high-pressure steam without the combination of the surface condenser for
supplying the boiler with distilled water; neither can the high-pressure steam
be fully utilized, or the condenser be reduced to its most compact and inex-
pensive form, without the additional combination of the system of maintaining
thecylinderata suitable temperature, and moreover many of the detail arrange-
ments depend upon thecombination of the whole,andwhich detail arrangements
I will set forth more particularlyhereafter. Before doing so, however, Iwill point
ontgenerallythe necessity for somemeans of preventingthe inconvenience and
danger thatfrequentlyarise to steamvessels fromthenumerous openings which
it is at present usual to make in them both at and below thewater line for the
various pipes for engines and boilers, &c. From the fact of these openings
being at or below the water line it happens when any derangement occurs to
any of the joints made between the skin of the vessel and the flanges of either
the pipes or cocks, or when any derangement occurs to any of the cocks
themselves, or to any of the pipes connected directly to the skin of the vessel,
and not having an intermediate cock to cut off the connection,that it is found
to be extremely difficult and often impossible to repair the damage while the
ship is at sea, and from the pouring in of the sea that ensues, although it may
not be sufficient to endanger the safety of the ship when the bilge pumps
are in good order, still the leakage causes considerable inconvenience by
drowning and rendering inaccessible the very joints requiring examination
and repair, so that many cases have occurred in which from so small a cause,
comparatively, steamers after having been laden with cargo, and having
put to sea, have had to put back again and be dry docked, not only at much
loss of time and money, but also at the risk of straining the vessel, from
being dry docked when fully loaded.
I prevent all chance of leakage from the connection of the flanges of the
pipes or cocks to the skin of the vessel, by dispensing entirely with such

page_text: connections, not requiring a single one in the entire ship, and in the event of
any accident occuring to any of the cocks or pipes themselves I can at any
time get at them conveniently to examine and repair them, or remove them
and put others in their place, and I can do this even while at sea with as
much safety and facility as when in dry dock. This is effected by a syphon
well or stand pipe, and will be clearly understood by referring to the detail
arrangements explaned hereafter, and which detail arrangements of the whole
of my Invention I will now more particularly set forth.
In the first place, arrangements relating to the boiler.-I do not confine
myself to any particular form of boiler, but in some cases where it is found
desirable, I construct the boiler in distinct compartments so that the steam,
when desirable but not necessarily, may be generated and maintained at a
higher pressure in one of the compartments than in the other, and the water
also, when desirable but not necessarily, may be kept at a higher level in one
compartment than in another. I am able by the aid of the artificial draft to
use tubes of much greater length and of smaller diameter than are now in use
in marine boilers, and thus without diminishing the effective heating or
absorbing surface I am able so much to reduce the transverse dimensions of
the boiler, that without requiring plates of a disadvantageous thickness, I can
include within the limits of the circle an amount of heating surface sufficient
for much higher powers than has hitherto been at all practicable, and thus
make use of circular boilers more generally than at present. I also add at
the ends of the tubes a heater for the feed water, which, with the ordinary
chimneydraft would behighly injurious to the evaporative power of the boiler.
To ensure the mixture and combustion of the gases in the furnace I am able
without injury to the draft when urged by mechanical means, to place an
inverted or hanging bridge in the furnace behind the ordinary fire bridge,
and I prefer to build both these bridges of fire brick, with which material I
also line the lower portion of the flame chamber as high as may be desir-
able. This inverted bridge also has the advantage of preventing the passage
of some of the smaller particles of fuel into the tubes, and thus preventing
their being so soon choked, and further to prevent these small particles
being carried up the chimney and then scattered on deck, I add a fine sieve
screen and adopt-a-sudden turn in the direction of the current, or any ap-
proved form of spark arrester.
The artificial draft I produce by two different systems, viz., by pressure or
by exhaustion, or by a combination of both; when I effect this by pressure I
submit the whole stokehole or boiler room, or even the whole engine room as
well when convenient, to an artificial pressure of air which escapes through

page_text: of
the furnaces and through the tubes into the chimney. I thus dispense with
the close ash-pit doors rendered necessary when the pressure is confined to
the ash-pit, and obviate the consequent difficulty experienced in firing. I
sustain this artificial atmosphere by blowing direct into the stokehole, boiler
room, or engine room, as may be most convenient, and I confine it therein by
adopting double doors or other suitable means for closing points of entrance
or other openings, allowing a sufficient quantity to escape for purposes
ventilation. The general arrangement which I decidedly prefer is to divide
the engine room entirely from the boiler room by a bulkhead carried across the
vessel or as far as may be sufficient for the purpose, and which depends on the
arrangement of the coal bunkers; I then place the boiler fore and aft, making
an athwart stokehole, and turn the back of the boiler towards the engine,
and place it within about 15 inches of the aforesaid bulkhead. I also place a
partial bulkhead or screen in front of the boiler so as to cover over the space
round the boiler formed between the sides of the boiler and the sides of the
stokehole,and between the top of the boiler and the top or roof of the stoke-
hole. Through this screen a door or doors are made for convenient access to
the ordinary smoke box doors. The boiler is thus entirely enclosed in a hot-
air chamber, in which a clear space is left all round the boiler to allow room
for its examination and repair,and the boiler being thus guarded from currents
of cold air,coating with its attendant disadvantages is rendered unnecessary.
I then blow the air into the stokehole direct, in which from its compactshape
and size the pressure of the artificial atmosphere can be readily maintained.
I connect the water gauges, pressure gauges, scum cocks, blow-off cocks, and
other fittings to the back of the boiler, and carry them through the partition
bulkhead (already alluded to), to which they are fixed on the engine room
side, so that they are all under the command of the engineer in the engine
I make a communication between the engine room and stokehole,
on one side of the boiler through the coal bunkers, as the case may be.
room.
I adopt this arrangement and position of boiler, whatever the number of
boilers may be, and whether the boiler or boilers are placed forward or aft
of the engine or engines, or both forward and aft.
When this artificial draft is effected by exhaustion, I prefer to place thé
boilers in the same position, and make the same arrangements as far as
possible as I have just mentioned for the draft when produced by pressure.
With regard to the means of producing the draft, whether under the pressure
or exhaust system, I make use of a fan of any approved construction, or of a
blowing cylinder, or of a gassometer pump, or of any other convenient means,
and whatever plan may be adopted, although I may sometimes avail myself

page_text: of the main engine, I prefer to employ as the driving power, a separate or
auxiliary engine or auxiliary engines to be worked independently of the main
engine or engines, and which may be employed also to work any pumps or
cranes, or winding gear, or any machinery in the vessel whatever; and this
auxiliary engine or these auxiliary engines may either be supplied with steam
from the main boiler or boilers, and should the main steam boiler or boilers
be constructed in distinct compartments, as previously described, then the
auxiliary engine or engines may be worked from any of these compartiments,
or they may have their own independent boiler or boilers, to be worked at
a higher pressure than the main boiler or boilers, and from which auxiliary
high-pressure steam boiler or boilers a supply of steam may be taken to
work the cylinders of steam winches, cranes, or any other working gear or
machinery whatever on board the vessel; and this auxiliary engine, or these
auxiliary engines, may either exhaust into the atmosphere or into their own
independent condenser, or into the condenser of the main engine or engines,
or into the main steam boiler or boilers.
In the second place, arrangements relating to the engine.-1 recommend
the use of three cylinders, since that arrangement, on account of its balancing
the moving parts, renders practicable a higher speed of piston, from which I
think economy will result both in the weight of the engine and in the use of
the steam, and as it is not desirable to drive air-pumps rapidly, or especially to
submit them to the irregular speed to which the main engines are liable in
rough weather from the pitching of the vessel, I propose to drive the air-
pumps by an auxiliary engine or by auxiliary engines, which may work
independently of the main engine or engines at any convenient speed, and
when desirable,I make the auxiliary engine employed for exciting the artificial
draft, and already described, also drive the air pump or air
pumps. The
cylinders of the main and auxiliary engines I entirely surround with a steam-
jacket, including the covers, both top and bottom, added to which, where
desirable, I fix on one or both sides of the piston a heater, consisting of a
coil of pipe or any other convenient form, through which a current of steam
or hot water or any convenient liquid may circulate, and which circulation
is effected through any convenient arrangement of pipes attached thereto,
and passing through either cylinder cover.
Where cylinders have been constructed without steam jackets, I propose
either to take out the old cylinders and put in new ones constructed with
steam jackets, or to put a cylinder of slightly smaller diameter inside the old
one, so as to form a small annular space between the two, and then to allow
steam to circulate through this space, and in either case to fit the cylinders

page_text: with steam covers and also the piston with the heater just explained, when
thought desirable, and in some cases I propose to fit the steam covers only, or
the piston heaters only, or the two in conjunction without the jackets. And
as a convenient plan for adding steam covers to the bottom of the cylinder
in cases where the engines were originally made without them, I propose to
fix a steam casing to the bottom of the cylinder inside it, and in order to gain
sufficient room for this addition, and also for the piston heater, I propose to
recess or dish the piston, and also recess the top cylinder cover and to intro-
duce two piston rods. I have three methods of feeding these jackets and
their appurtenances with steam, either one of which I use as found convenient.
First, I connect the jacket and its appurtenances with the main boiler in the
ordinary way,and in order to insure a regular circulation of the steam through
the said jacket and appurtenances I employ a small pump or pumps, by
which I draw from the jacket and its appurtenances and pump into the boiler,
or I use the pump or pumps in any other convenient method to attain the
same end. And this pump or these pumps may be worked by the main or
auxiliary engines, or by hand, or the circulation may be effected by the assist-
ance of any of the other pumps belonging to the main or auxiliary engines,
or by any combination of the same. The application of this
is
pump par-
ticularly adapted to marine engines, since the cylinders are seldom much
above the level of the water in the boilers, and in horizontal engines are even
below it entirely. Second, I connect the jacket and its appurtenances with
the auxiliary high-pressure boiler or boilers already referred to, to any other
high-pressure boiler on board the vessel, and I allow the high-pressure steam
to circulate entirely round the cylinder through the jacket and appurtenances,
and then below through into the main boiler or boilers, and I control the current
by a weighted valve or throttle, as may be found convenient. Third, when the
boiler is constructed in distinct compartments, as previously described, I con-
nect the jacket and its appurtenances with the high-pressure compartment,
and allow the steam to circulate entirelyround the cylinder through the jacket
and appurtenances and below through to the low-pressure compartment,and
I control the current by 24 weighted valve or throttle, as may be found most
convenient. I do not contine myself, however, to the use of steam for heating
the cylinders, but when desirable make use of hot water or other suitable
means for that purpose. In cases where I do not think it desirable to apply
steam jackets, steam covers, or piston heaters, or to apply heat directly to the
cylinder in any way, I superheat the steam before it enters the cylinder, and
in some cases I do so in combination with the steam jacket, steam cover, and
B

page_text: piston heater, or other approved means of applying heat direct to the
cylinder or in combination with any one or more of these.
In the third place, arrangements relating to the condenser.-I do not con-
fine myself to any particular form of condenser, but from the combination
with it of the detail arrangements already mentioned I am able to supply the
most important. desideratum of making up any waste of distilled water that
may arise from leakage, blowing off the safety valves, or any other cause. I
do this by feeding the auxiliary boiler or boilers with sea or river water, as
the case may be, or should there be no auxiliary boiler I construct the main
steam boiler or boilers in distinct compartments, as already explained, and I
feed the high-pressure compartment or compartments with sea or river water,
as the case may be; and it will be seen from this arrangenient that whether
the steam from these is blown through the steam jacket into the main
steam boiler, or whether it first works the auxiliary engine and then exhausts
into the condenser of the main engine or engines, or exhausts into the main
steam boiler, that the effect is the same, viz., that the whole arrangement
acts as a still, and that the sea or river water evaporated in the auxiliary
boiler or boilers, or high-pressure compartment of the main steam boiler or
boilers, passes over and adds to the stock of the distilled water already in
the main boiler or boilers; and it will be apparent that by this arrangement
the supply of distilled water is entirely independent of any attention from
the engineer, and must go on regularly as long as the engines and boilers are
kept at their regular work. I blow out in the ordinary way the boiler or
boilers in which the undistilled water is evaporated, and recommend the
use of more than one, so that there may be a spare one for cleaning out.
In the fourth place,arrangements relating to the hot and cold water connec-
tions for engines and boilers.-I fix a trunk to the shell of the vessel at any
convenient point,sufficiently below the vessel's light water line,and I prefer to
fix this trunk in a vertical position, and I carry it up to any convenient extent
above the level of the vessel's load water line, and in vessels where there is
sufficient room I make the trunk large enough to admit a workman to the
inside, and I prefer to make it of iron, especially in iron vessels, in which case
I secure it to the hull by a careful double rivetted metal to metal joint, which
can evidently be made as secure as any of the joints of the plates in the hull
of the vessel; or, I adopt any other method, if more desirable, for securing
this trunk to the shell of the vessel. I make a few perforations through the
hull inside and at the bottom of this trunk, so that the water surrounding the
vessel can flow into it and keep it filled at all times; I supply this trunk with

page_text: a moveable cover and fit on to the top with an air-tight joint; I then bolt the
flanges of the necessary pipes and cocks to this trunk at anyconvenient position
above the level of the vessel's load water line, and it will be apparent that the
trunk and pipes connected to it form a syphon, and that its action may at any
time be stopped by admitting air into the upper part of the trunk, and for con-
veniently effecting which I introduce a cock with a handle for opening and
shutting the same, led either to the deck or to some easily accessible place, so
that by merely opening this cock the water in the trunk will at once subside
below the level of any of the openings in it, and the connections can then be
examined and repaired. And as a further safeguard, I propose to have a
moveable plate made to fit on to the shell of the vessel at the bottom of and
inside the trunk, so as to cover over and close the perforations, and which plato
can be dropped down from the top of the trunk and firmly secured in its place
while the water is standing in the trunk. In the event of the perforations at
the bottom of the trunk becoming choked with mud or fouled with weeds, it
will be clear that such obstructions can be removed by opening the trunk at
the top and making use of a scraper, or should it be desirable for a workman
to enter the trunk while at sea, with the perforations at the bottom open, I
propose to drive the water out of the trunk at the bottom by forcing air in at
the top, as in a diving bell, for which purpose I presume it will not be necessary
in large vessels to carry a special air force pump, since no large steamer should
go to sea without a complete diving apparatus and its attendant set of air
pumps, which could be applied to this purpose; but should this not be the
case, I propose to carry the requisite air pump, or else to adapt one of the.
engine pumps to the purpose. This syphon well or stand pipe admits of many-
modifications. In some cases I prefer to introduce a partition inside the trunk
carried up a little above the level of the vessel's load water line, so as to com-
plete the syphon within the trunk itself, and then the connections for the
engines and boilers, &c.,can be made to the trunk at any convenient height, and
not necessarily as in the previous arrangement above the level of the vessel's
load water line. And in other cases I propose as a double security to fix to
the shell of the vessel two trunks, one inside, the other, the inner one, being
carried up only a little above the level of the vessel's load water line, and the
outer one beyond the inner one to any convenient extent. I propose to fix
one or more of these syphon wells as may be found convenient, in some cases
one for the inlets and another for the outlets, although I think one syphon
well will generally be found sufficient, since the openings in the hull for the
outlets can generally be made above the load water line, and should it be
found desirable to connect the blow-off outlet to the inlet syphon well, Ido not

page_text: apprehend that any inconvenience would arise from so intermittent a dis-
charge of hot water amongst the incoming current, but, on the contrary,
that convenience would arise from its scouring out the perforations at the
bottom of the trunk.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Lavington Evans Fletcher in the Great Seal Patent Office
on the 17th September 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, LAVINGTON
EVANS FLETCHER, of Upper Norwood, in the County of Surrey, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of March, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Lavington Evans Fletcher, Her special licence, that I, the said
Lavington Evans Fletcher, my executors, administrators, and assigns, or
such others as I, the said Lavington Evans Fletcher, my executors, adminis-
trators, 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 MARINE ENGINES AND BOILERS, AND
THEIR APPURTENANCES," upon the condition (amongst others) that I, the
said Lavington Evans Fletcher, my executors or administrators, by an in-
strument in writing under my, or their, or one of their hands and seals, 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
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Lavington Evans Fletcher, 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 :-
The object of my Invention is to promote the economy and safety of steam
navigation by effecting a saving in the consumption of fuel, which has so
important an influence on the profitable working of steamers of all classes,
but more especially of those engaged in long ocean voyages, and by pre-

page_text: venting the inconvenience and danger that frequently arise to steam vessels
from the numerous openings which it is at present usual to make in them,
both at and below the water line for the various pipes for engines and
boilers, &c., while at the same time my Invention secures many incidental
advantages, some of which are as follows:-I reduce the weight of the
engines and boilers, which is of importance to steamers required to draw little
water for the navigation of shallows, in addition to which I am able to burn
both smokelessly and efficiently every description of coal, even the most
highly bituminous north country coals, such as the Hartleys, &c, and at the
same time I render the engine and boiler room more comfortable and healthy
by considerably reducing their temperature, which is generally most incon-
veniently high, especially in hot climates, while by the reduction of the
amount of fuel necessary to be carried for the consumption of the boilers, I
am thereby able to add to the available and remunerative space for passengers
and cargo.
I produce this saving of fuel by a more economic generation of
steam in the boiler in the first place, and by utilizing the steam more fully in
its expenditure in the engine in the second place.
In the first place, the economic generation of steam in the boiler.-The
economic production of steam is principally dependent upon the perfect com-
bustion of the fuel, which is at present extremely imperfect in marine boilers,
arising from the fact that the value of space on board a steamer limits the
size of the boiler, and thus a very heavy duty is imposed upon it, and more
especially upon the furnaces, in which an amount of fucl quite unusual in
stationary engines has to be consumed per square foot of fire-grate surface.
The thick fires consequent on this are too much for the natural draft produced
by a chimney, more especially by such chimneys as are admissible on board
ship, and the present draft, imperfect as it is, is only produced by a most
extravagant expenditure of heat in the chimney, which creates great incon-
venience by heating the smoke-box doors, and thus raising the temperature
of the boiler room and engine rcom, much to the discomfort and injury to
the health of the engineers, especially in hot climates, as well as injuring the
base of the chimney, and even in some cases setting fire to the deck. These
thick fires obtain only an imperfect supply of air, the consequence of which is
imperfect combustion, the formation of smoke, and waste of fuel. I remedy
these very serious defects by using mechanical means for stimulating the
draft, and thus I can obtain any amount that may be found necessary, and
secure a sufficient supply of air for perfect combustion, and the entire
prevention of smoke, even with thick fires and bituminous coals.
Having this command of the draft, I am able to introduce arrangements

page_text: which are hereafter more fully set forth (which have been hitherto in-
admissible). into the furnace for the more complete mixture and combustion
of the gases, and also to introduce proportions into the boiler for the more
complete absorption and utilization of the heat resulting therefrom, and thus
by retaining the heat in the boiler instead of allowing it to escape into the
smoke box, I prevent the inconvenience previously mentioned which is
oxperienced at the smoke-box doors and base of chimney. In addition to
utilizing more fully the fuel consumed, I am also enabled by the application
of the artificial draft to marine boilers so to increase their evaporative power
as to reduce their size and consequently their weight, from which many
advantages arise. From the diminution of the weight of the boiler steamers
may be built of lighter draft of water, the advantage of which has already
been alluded to, and from the diminution in the size of the boilers 1 am able
to leave a space all round them, so as to afford room for convenient access
'for examining and repairing them. And I place them in a hot air chamber,
so that the use of any coating to prevent radiation of heat is unnecessary, and
thus the shell being uncovered is less liable to corrosion, and can the more
readily be examined. I am also able from the reduced size of the boilers to
place them in a more convenient position (hereafter more fully set forth)than
would be possible with boilers of the ordinary size, and also to effect other
neat and suitable arrangements of details conducive to the efficient discharge
of the engineer's duty, and to which I consequently attach importance; and
I am further able from the reduced size of the boilers to make them stronger
with the same or even with a less weight of metal, and thus safely to use
steam of a higher pressure, from which much economy will result.
And in order to promote still further the economic generation of steam in
the boiler, I combine with the artificial draft a system of condensing by cold
surfaces instead of by injection, by which means I feed the boiler constantly
with distilled water, instead of either with sea or river water, as the case may
be, and thus save the waste of heat consequent on the frequent blowing-out
rendered necessary by the use of this sea or river water, and keep the boiler
free from deposit of any sort whatsoever. This enables me to reduce the width
of the water spaces, and thus to make another reduction in the size and
weight of the boiler in addition to that already explained. And my Invention
further provides a method for supplying or making up any waste of the dis-
tilled water that may arise from leakage or blowing-off from the safety valves
or any other cause, and which method I prefer to any of the numerous plans
that have been proposed for effecting this object.
I consider surface condensation a very important accessory to the artificial

page_text: draft, and that without it the full benefit of the artificial draft cannot be
realized, since by the use of distilled water in the boiler I am able to urge
the fires to, a much higher intensity than would otherwise be at all prudent,
considering the boiler's durability, and in addition to which, by combining
the reductions made in the weight of the boiler by each system separately,
as already explained, I am able so considerably to modify the proportions
and shape of the boiler as to introduce forms hitherto not used and inad-
missible on board ship except for engines of small power, and I can thus:
make use safely of steam of a much higher pressure than has hitherto been
at all practicable.
In the second place, arrangements for utilizing the steam more fully in its
expenditure in the engine:-Although the boiler may be adapted for supplying
high-pressure steam, as just explained, still unless this steam is suitably used
in the engines its generation will prove comparatively fruitless, since the full
advantage of steam of any pressure cannot be realized without expansion,
and more especially that of high-pressure steam, which requires to be expanded
considerably to develope its power fully. Very much of the advantage,
however, of working steam expansively. is at present lost in marine engines
from the temperature of the cylinder not being sufficiently maintained, for, in
addition to the loss of heat from external radiation, the expansive action of
the steam within the cylinder has such a cooling effect that the cylinder
becomes colder than the steam which enters it from the boiler, and thus, from
the rapid conducting power of the metal of the cylinder; there is set up
within it an action which has received too little attention, but which exercises
a highly injurious.effect upon the economical expenditure of the steam:!This
action consists of an alternate condensation and evaporation, which takes
place upon the internal surface of the cylinder as well as on the piston, and
which entails upon the boiler an extra and entirely unproductive amount of
evaporative duty, and on the condenser a corresponding amount of unneces-
sary condensation; and this alternate condensation and evaporation can only
be arrested by maintaining the cylinder at a temperature at least as high as
that of saturated steam at the initial pressure; whether this be effected by
superheating the steam before entering the cylinder, or by applying, heat
directly to the metal of the cylinder itself. The adoption of suitable means
for maintaining the temperature of the cylinder will, it is therefore clear, have
an important effect upon the system of surface condensation, since byarresting
the action of evaporation just alluded to, and, thus saving a considerable
amount of useless duty otherwise imposed upon the condenser, it follows that

page_text: a smaller amount of cooling surface will suffice, and the first cost and size
of the condenser be consequently reduced.
.
I have now stated generally the points relating to economy in marine
engines which my Invention effects, and will briefly recapitulate for greater
clearness: -I effect a more rapid and complete combustion of the fuel, and
obtain a more perfect absorption and consequent utilization of the heat
generated therefrom; I feed the boiler constantly with distilled water; I
generate steam at a higher pressure than has hitherto been usual, and more
fully utilize its expansive action. I thus considerably reduce the consumption
of fuel, and at the same time lower the inconvenient and unhealthy tem-
perature of the engine and boiler rooms, as well as reducing the weight of
engines and boilers and the size of coal bunkers. I effect this by the novel
combination of three systems; first, that of the artificial draft; second, that
of condensation by cold surfaces instead of by injection; and, thirdly, that of
maintaining the cylinder at a sufficiently high temperature to prevent con-
densation and evaporation going on upon the internal surfaces. Without this
entire combination the full advantage of neither one of these systems can be
realized. Full advantage cannot be taken of the artificial draft for urging
the fire to its greatest intensity, nor can the boiler be reduced to its strongest
form for the generation of high-pressure steam without the combination of
the surface condenser for supplying the boiler with distilled water; neither
can the high-pressure steam be fully utilized, or the condenser be reduced to
its most compact and inexpensive form, without the additional combination of
the system of maintaining the cylinder at a suitable temperature; and,
moreover, many of the detailed arrangements depend upon the combination
of the whole, and which detail arrangements I will set forthmore particularly
hereafter. Before doing so, however, I will point out generally the necessity
for some means of preventing the inconvenience and danger that frequently
arise to steam vessels from the numerous openings which it is at present usual
to make in them, both at and below the water line, for the various pipes for
engines and boilers, &c. From the fact of these openings being at or below
the water line, it happens, when any derangement occurs to any of the joints
made between the skin of the vessel and the flanges of either the pipes o
cocks, or when any derangement occurs to any of the cocks themselves, or to
any of the pipes connected directly to the skin of the vessel, and not having
an intermediate cock to cut off the connection, that it is found to be extremely
difficult and often impossible to repair the damage while the ship is at sea
and from the pouring in of the sea that ensues, although it may not be

page_text: sufficient to endanger the safety of the ship when the bilge pumps are in
good order, still the leakage causes considerable inconvenience by drowning
and rendering inaccessible the very joints requiring examination and repair,
so that many cases have occurred in which from so small a cause, com-
paratively, steamers after having been laden with cargo, and having put to
sea, have had to put back again and be dry docked, not only at much loss
of time and money, but also at the risk of straining the vessel, from being
dry docked when fully loaded.
I prevent all chance of leakage from the connection of the flanges of the
pipes or cocks to the skin of the vessel by dispensing entirely with such
connections, not requiring a single one in the entire ship; and in the event
of any accident occurring to any of the cocks or pipes themselves I can at
any time get at them conveniently to examine and repair them, or remove
them and put others in their place, and I can do this even while at sea with
as much safety and facility as when in dry dock. This is effected by a syphon
well or stand pipe, and will be clearly understood by referring to the detail
arrangements explained hereafter, and which detail arrangements of the
whole of my Invention I will now more particularly set forth.
In the first place; arrangements relating to the boiler.-I do not confine
myself to any particular form of boiler, but in some cases where it is found
desirable I construct the boiler in distinct compartments, so that the steam
when desirable, but not necessarily, may be generated and maintained at a
higher pressure in one of the compartments than in the other; and the water
also, when desirable, but not necessarily, may be kept at a higher level in one
compartment than in another. I am able, by the aid of the artificial draft, to
use tubes of much greater length and of smaller diameter than are now in use
in marine boilers; and thus without diminishing the effective heating or
absorbing surface, I am able so much to reduce the transverse dimensions of
the boiler, that without requiring plates of a disadvantageous thickness, I can
include within the limits of the circle an amount of heating surface sufficient
for much higher powers than has hitherto been at all practicable, and thus
make use of circular boilers more generally than at present. I also add at
the ends of the tubes a heater for the feed water, which, with the ordinary
chimney draft, would be highly injurious to the evaporative power of the
boiler. To insure the mixture and combustion of the gases in the furnace, I
am able without injury to the draft, when urged by mechanical means, to
place an inverted or hanging bridge in the furnace behind the ordinary fire
bridge, and I prefer to build both these bridges of fire brick, with which
material I also line the lower portion of the flame chamber as high as may be

page_text: desirable. This inverted bridge also has the advantage of preventing the
passage of some of the small particles of fuel into the tubes, and thus pre-
venting their being so soon choked; and further to prevent these small
particles being carried up the chimney and then scattered on deck, I add a
fine sieve screen, and adopt a sudden turn in the direction of the current, or
any approved form of spark arrester.
Figure 1 of the accompanying Drawing is a longitudinal section, and
Figure 2 is a transverse section of a portion of a marine boiler, the furnaces
of which are provided with inverted or hanging bridges. A is the outer shell
of the boiler; B, B, are the furnaces; C, C, are the fire-bars; D is the
uptake; E is the ordinary bridge; F is a fire-brick lining in the flue or
flame chamber behind the bridge E; G is the hanging bridge, which is an
arch of fire-brick, under which the air and gases from the furnace have to
pass before ascending the uptake. The lining F is not essential and may be
omitted. The arch G may spring from and be supported by brackets or angle
irons rivetted to the sides of the fluc. The artificial draft I produce by two
different systems, viz., by pressure or by exhaustion, or by a combination of
both. When I effect this by pressure I submit the whole stokehole or
boiler room, or even the whole engine room as well when convenient, to an
artificial pressure of air, which escapes through the furnaces and through the
tubes into the chimney. I thus dispense with the close ash-pit doors rendered
necessary when the pressure is confined to the ash-pit, and obviate the
consequent difficulty experienced in firing. I sustain this artificial atmosphere
by blowing direct into the stokehole, boiler room, or engine room, as may be
most convenient, and I confine it therein by adopting double doors or other
suitable means for closing points of entrance or other openings, allowing a
sufficient quantity to escape for purposes of ventilation.
The general arrangement which I decidedly prefer is, to divide the engine
room entirely from the boiler room by a bulkhead carried across the vessel,
or as far as may be sufficient for the purpose, and which depends on the
arrangement of the coal bunkers; I then place the boiler fore and aft,
making an athwart stokehole, and turn the back of the boiler towards the
engine and place it within about 15 inches of the aforesaid bulkhead. I also
place a partial bulkhead or screen in front of the boiler, so as to cover over
the space round the boiler formed between the sides of the boiler and the
sides of the stokehole, and between the top of the boiler and the top or.roof
of the stokehole. Through this screen a door or doors are made for con-
venient access to the ordinary smoke box doors. The boiler is thus entirely
inclosed in a hot air chamber, in which a clear space is left all round the

page_text: boiler to allow room for its examination and repair; and the boiler being thus
guarded from currents of cold air, coating with its attendant disadvantages
is rendered unnecessary. I then blow the air into the stokehole direct, in
which, from its compact shape and size, the pressure of the artificial atmo-
sphere can be readily maintained. I connect the water guages, pressure
guages, scum cocks, blow-off cocks, and other fittings to the back of the
boiler, and carry them through the partition bulkhead (already alluded to), to
which they are fixed on the engine room side, so that they are all under the
command of the engineer in the engine room. I make a communication
between the engine room and stokehole on one side of the boiler or through
the coal bunkers, as the case may be. I adopt this arrangement and position
of boiler, whatever the number of boilers may be, and whether the boiler or
boilers are placed forward or aft of the engine or engines, or both forward and
aft. When the artificial draft is effected by exhaustion, I prefer to place the
boilers in the same position, and make the same arrangements as far as
possible as I have just mentioned for the draft when produced by pressure.
With regard to the means of producing the draft, whether under the pressure
or exhaust system, I make use of a fan of any approved construction, or of a
blowing cylinder, or of a gasometer pump, or of any other convenient means,
and whatever plan may be adopted, although I may sometimes avail myself of
the main engine, I prefer to employ as the driving power a separate or
auxiliary engine or auxiliary engines, to be worked independently of the main
engine or engines, and which may be employed also to work any pumps or
cranes or winding gear, or any machinery in the vessel whatever. And this
auxiliary engine or these auxiliary engines may either be supplied with steam
from the main boiler or boilers, and should the main steam boiler or boilers
be constructed in distinct compartments as previously described, then the
auxiliary engine or engines may be worked from any of these compartments,
or they may have their own independent boiler or boilers to be worked at a
higher pressure than the main boiler or boilers; and from which auxiliary high
pressure steam boiler or boilers a supply of steam may be taken to work the
cylinders of steam winches, cranes, or any other working gear or machinery
whatever on board the vessel. And this auxiliary engine or these auxiliary
engines may either exhaust into the atmosphere, or into theirown independent
condenser, or into the condenser of the main engine or engines, or into
main steam boiler or boilers.
By employing artificial draught, instead of the ordinary chimney draught,
I am enabled to employ smaller tubes than are ordinarily used, without any
danger of spoiling the draught by so doing. By using smaller tubes a greater

page_text: number of tubes and a larger amount of heating surface may be introduced
into the same space. If, however, the boiler were to be fed with salt water,
it would be dangerous to reduce the water spaces between the tubes in the
same proportion as the reduction in the diameter of the tubes; and therefore
little or no increase of surface would result from reducing the diameter of the
tubes; 1 obviate this defect, and obtain the full advantage of the small tubes,
by employing distilled water in the boiler; for which purpose the engine is
provided with a surface condenser. The distilled water obtained by the con-
densation of the steam in the surface condenser, is pumped back again into
the boiler. By thus combining an engine having a surface condenser with a
tubular boiler worked by artificial draught, I am enabled to construct the
boiler with small tubes and small water spaces, and thus to reduce the size
and weight, and increase the strength of the boiler. The artificial draught
enables me to burn a much larger quantity of coal per square foot of grate
than can be effected with the ordinary draught; and I am thus enabled to
reduce the area of fire-grate.
The size of the boiler for a given power being thus reduced, I am enabled to
obtain a sufficient amount of boiler power, even for large ships, in one or two
ranges of boilers placed across the vessel. I am thus enabled to effect the
arrangement herein-before mentioned of placing a range of boilers at each
end of the engine room, with their backs to the engine room, and with the
water guages and boiler fittings in the engine room, and under the control
of the engineer. The two stokeholes are then beyond the boilers.
By exhausting the steam from the engines which drive the fan or produce
the artificial draught, into the main boiler or boilers, instead of exhausting into
the atmosphere, or into the condenser of the main engines, or into a separate
condenser, I obtain the following advantages:-In first getting up steam in
the main boilers, I am enabled to work the auxiliary engine to its full power,
as the steam is condensed by the cold water in the main boilers. The heat
and the distilled water are not lost, being retained in the main boilers, while
the auxiliary engine is very simple, being a plain non-condensing high-
pressure engine. When the main engines are stopped or standing still after
steam has been raised in the main boilers, the auxiliary engine can still be
worked as much as may be required to keep up the steam, and may also be
used to work the feed pumps, if necessary; but the engineer should endeavour to
work the artificial draught only to such an extent as to maintain the pressure
of the steam without blowing off at the safety valves, so as to avoid loss of
distilled water. When the main engines are at work, the pressure in the main
boilers will be, to some extent, self-regulating; for if the pressure falls in the

page_text: inain boilers the auxiliary engine will have less back pressure, and will,
therefore, spontaneously accelerate its motion, and increase the draught of
the furnaces of the main boilers, and thus again raise or restore the pressure
in them.
In the second place, arrangements relating to the engine.-I recommend
the use of three cylinders, since that arrangement, on account of its balancing
the moving parts, renders practicable a higher speed of piston, from which, I
think, economy will result, both in the weight of the engine and in the use of
the steam; and as it is not desirable to drive air pumps rapidly, or especially
to submit them to the irregular speed to which the main engines are liable in
rough weather from the pitching of the vessel, I propose to drive the air
pumps by an auxiliary engine or by auxiliary engines, which may work inde-
pendently of the main engine or engines at any convenient speed, and, when
desirable, I make the auxiliary engine, employed for exciting the artificial.
draught already described, also drive the air pump or air pumps. The cylinders
of the main and auxiliary engines I entirely surround with a steam jacket,
including the covers both top and bottom, added to which, where desirable, I
fix on one or both sides of the piston a heater, consisting of a coil of pipe or
any other convenient form, through which a current of steam, or hot water, or
any convenient liquid may circulate, and which circulation is effected through
any convenient arrangement of pipes attached thereto, and passing through
either cylinder cover.
Where cylinders have been constructed without steam jackets, I propose
either to take out the old cylinders and put in new ones, constructed with
steam jackets, or to put a cylinder of slightly smaller diameter inside the old
one, so as to form a small annular space between the two, and then to allow
steam to circulate through this space, and in either case to fit the cylinders
with steam covers, and also the piston with the heater just explained, when
thought desirable; and in some cases I propose to fit the steam covers only,
or the piston heaters only, or the two in conjunction without the jacket. . And
as a convenient plan for adding steam covers to the bottom of the cylinder,
in cases where the engines were originally made without them, I propose
to fix a steam casing to the bottom of the cylinder inside it; and in order
to gain sufficient rooin for this addition, and also for the piston heater, [
propose to recess or dish the piston, and also recess the top cylinder cover,
and to introduce two or more piston rods.
Figure 3 is a longitudinal section of a steam engine cylinder and piston,
furnished with heaters according to my Invention.
A is the cylinder; B is the piston; C, C, are two piston rods, connected by

page_text: a short cross beam D to the cross head E, from which the connecting rod or
rods proceed to the crank or to the beam in the ordinary manner; F is a
heater, placed on the bottoin of the cylinder and provided with an inlet pipe a
and outlet b. This heater may be a flat box of copper or other suitable metal,
strengthened by stays, or it may be a coil of pipe. The bottom of the piston
B is recessed to receive the heater. G is a similar heater placed on the under
side of the piston, and H is another heater placed on the top of the pistou,
and connected to the heater G by a central pipe or passage. The cylinder
cover I is dished or recessed to admit the heater H. c is the inlet pipe for
conveying steam into the heater G, and from it into the heater H. d is the
outlet pipe for the escape of the condensed water; these pipes pass through
stuffing boxes on the cylinder cover I, and on the ends of two larger pipes
c and f. By connecting the pipe e to the auxiliary boiler, or to the high-
pressure compartment of the main boiler, and the pipe f to the main boiler or
to the low-pressure compartment of the same, a constant supply of heat is
afforded to the piston, and a constant supply of distilled water to the main
boiler. It is, however, necessary to check the escape of the condensed water
to such an extent as to maintain the pressure in the heaters, which I effect by
means of a cock or valve on the exit pipe f, or by means of a loaded valve,
which the water is obliged to raise before it can escape into the main boiler
or low-pressure compartment of the same. It is important that this check
should be placed in the outlet and not upon the inlet, for if the inlet be
checked and the outlet left free, the pressure, and consequently the tempera-
ture in the heaters, would scarcely exceed that in the main boiler or low-
pressure compartment of the same. This observation applies equally to the
case of steam jackets to the sides and ends of the cylinders, and whether they
exhaust into the main boiler or boilers, or into the condenser or the atmosphere.
I have three methods of feeding these jackets and their appurtenances with
steam, either one of which I use as found convenient. First, I connect the jacket
and its appurtenances with the main boiler in the ordinary way, and in order
to insure a regular circulation of the steam through the said jacket and appur-
tenances, I employ a small pump or pumps, by which I draw from the jacket
and its appurtenances and pump into the boiler; or I use the pump or pumps
in any other convenient method to attain the same end; and this pump or
these pumps may be worked by the main or auxiliary engines, or by hand, or the
circulation may be effected by the assistance of any of the other pumps belong-
ing to the main or auxiliary engines, or by any combination of the same.
The application of this pump is particularly adapted to marine engines, since
the cylinders are seldom much above the level of the water in the boiler and

page_text: in horizontal engines are even below it entirely. By placing a valve opening
inwards in the inlet pipee, or a valve opening upwards in the pipe din Figure3,
and another valve opening outwards in the pipe f, the motion of the pipes
c and d may in some cases be made available for pumping the steam or con-
densed water back to the boiler. Second, I connect the jacket and its appur-
tenances with the auxiliary high-pressure boiler or boilers already referred to,
or to any other high-pressure boiler on board the vessel, and I allow the high-
pressure steam to circulate entirely round the cylinder through the jacket and
appurtenances, and then blow through into the main boiler or boilers, and I
control the current by a weighted valve or throttle, as may be found con-
venient. Third, when the boiler is constructed in distinct compartments, as
previously described, I connect the jacket and its appurtenances with the
high-pressure compartment and allow the steam to circulate entirely round the
cylinder through the jacket and appurtenances, and blow through to the low-
pressure compartment, and I control the current by a weighted valve or
throttle, as may be found most convenient. I do not confine myself, how-
ever, to the use of steam for heating the cylinders, but when desirable
make use of hot water or other suitable means for that purpose. In
cases where I do not think it desirable to apply steam jackets, steam
covers, or piston heaters, or to apply heat directly to the cylinder in any
way, I superheat the-steam before it enters the cylinder, and in some cases
I do so in combination with the steam jacket, steam cover, and piston
heater, or other approved means of applying heat direct to the cylinder, or
in combination with any one or more of these.
In the third place, arrangements relating to the condenser.-I do not con-
fine myself to any particular form of condenser, but from the combination with
it of the detail arrangements already mentioned I am able to supply the most
important desideratum of making up any waste of distilled water that may
arise from leakage, blowing-off the safety valves, or any other cause. I do
this by feeding the auxiliary boiler or boilers with sea or river water, as the
case may be, or should there be no auxiliary boiler, I construct the main steam
boiler or boilers in distinct compartments as already explained, and I feed the
high-pressure compartment or compartments with sea or river water, as the
case may be, and it will be seen from this arrangement, that whether the steam
from these is blown through the steam jacket into the main steam boiler, or
whetter it first works the auxiliary engine, and then exhausts into the main
steam boiler, that the effect is the same, viz., that the whole arrangement acts
as a still, and that the sea or river water evaporated in the auxiliary boiler or
boilers, or high-pressure compartment of the main steam.boiler.or. boilers,

page_text: passes over and adds to the stock of the distilled water already in the main
boiler or boilers, and it will be apparent that by this arrangement the supply
of distilled water is entirely independent of any attention from the engineer,
and must go on regularly as long as the engines and boilers are kept at their
regular work. I blow out in the ordinary way the boiler or boilers, in which
the undistilled water is evaporated, and recommend the use of more than one,.
so that there may be a spare one for cleaning out.
In the fourth place, arrangements relating to the hot and cold water con-
nections for engines and boilers.-I fix a trunk to the shell of the vessel at any
-convenient point sufficiently below the vessel's light water line, and I prefer
to fix this trunk in a vertical position, and I carry it up to any convenient
extent above the level of the vessel's load water line, and in vessels where
there is sufficient room, I make the trunk large enough to admit a work-
man to the inside, and I prefer to make it of iron especially in iron vessels,
in which case I secure it to the hull by a careful double rivetted metal to
metal joint, which can evidently be made as secure as any of the joints of the
plates in the hull of the vessel, or I adopt any other method, if more desirable,
for securing this trunk to the shell of the vessel. I make a few perforations
through the hull inside and at the bottom of this trunk, so that the water
surrounding the vessel can flow into it and keep it filled at all times. I supply
this trunk with a moveable cover, and fit it on to the top with an air-tight
joint. I then bolt the flanges of the necessary pipes and cocks to this trunk,
at any convenient position above the level of the vessel's load water line, and
it will be apparent that the trunk and pipes connected to it form a syphon, and
that its action may at any time be stopped by admitting air into the upper
part of the trunk, and for conveniently effecting which, I introduce a cock with
a handle for opening and shutting the same, led either to the deck or to some
easily accessible place, so that by merely opening this cock, the water in the
trunk will at once subside below the level of any of the openings in it, and the
connections can then be examined and repaired; and as a further safeguard I
propose to have a moveable plate, made to fit on to the shell of the vessel at
the bottom of and inside the trunk, so as to cover over and close the perfora.
tions, and which plate can be dropped down from the top of the trunk and
In the
firmly secured in its place while the water is standing in the trunk.
event of the perforations at the bottom of the trunk becoming choked with
mud, or fouled with weeds, it will be clear that such obstructions can be
removed by opening the trunk at the top, and making use of a scraper, or
should it be desirable for a workman to enter the trunk while at sea, with the
perforations at the bottom open, I propose to drive the water out of the trunk at

page_text: but
the pottom by forcing air in at the top, as in a diving bell, for which purpose I
presume it will not be necessary in large vessels to carry a special air force pump,
since no large steamer should go to sea without a complete diving apparatus,
and its attendant set of air pumps, which could be applied to this purpose;
should this not be the case, I propose to carry the requisite air pump, or else
to adapt one of the engiue pumps to the purpose. This syphon well or stand
pipe admits of many modifications; in some cases, I prefer to introduce a
partition inside the trunk, carried up a little above the level of the vessel's load
water line, so as to complete the syphon within the trunk itself, and then the
connections for the engines and boilers, &c., can be made to the trunk at any
convenient height, and not necessarily as in the previous arrangement, above
the level of the yessel's load water line; and in other cases, I propose as a
double security, to fix to the shell of the vessel two trunks, one inside the other,
the inner one being carried up only a little above the level of the vessel's load
water line, and the outer one beyond the inner one to any convenient extent.
I propose to fix one or more of these syphon wells, as may be found convenient;
in some cases, one for the inlets and another for the outlets, although I
think one syphon well will generally be found sufficient, since the openings
in the hull for the outlets can generally be made above the load water line,
and should it be found desirable to connect the blow-off outlet to the inlet
syphon well, I do not apprehend that any inconvenience would arise from so
intermittent a discharge of hot water amongst the incoming current, but,
on the contrary, that convenience would arise from its scouring out the
perforations at the bottom of the trunk.
Figure 4 represents a section of a syphon well constructed according to my
Invention, when full of water and in action; Figure 5 represents the same when
thrown out of action by admitting air. A is a portion of the shell or skin of the
vessel; B, B, is the load water line; C is the syphon well securely rivetted to
the skin of the vessel, which is perforated with holes at a, a, to admit the
water; Disa partition in the well; b, b, are places at which the various pipes
are connected to the well; E is the cover, and F is an air pipe, with a cock G
for admitting air into the syphon well. The top of the partition D rises above
the level of the water on the exterior. In the ordinary way the cock G is
closed, and the pumps draw from the syphon well, and receive the water
without interruption; but in the event of any accident to the pipes or connec-
tions, or if those parts require examination or repair, the cock G is opened, and
air then enters the upper part of the syphon well, and the water subsides to the
level of that on the exterior, as shewn in Figure 5. The connections of the
pipes at b, b, can. now be examined and removed, and again replaced without

page_text: any influx of water into the ship beyond the trifling quantity contained
between the partition 1) and the side of the well, and even this small
quantity may if desired be drawn off into buckets, through a cock at the side
of the well, before disconnecting the pipes.
Having now described the nature of the said Invention, and in what manner
the same is to be performed, I wish it to be understood that I do not claim
generally or separately the use or application of artificial draught to steam
boilers, nor the hanging bridge, nor surface condensers, nor steam jackets,
nor auxiliary engines and boilers; but what I claim is,―
First, the mode of applying an artificial draught to the furnaces of marine
boilers by forcing air into a close stokehole, in which the stokers work, and
thus maintaining a greater pressure of air in such stokehole than that of the
external atmosphere, as herein-before described.
Second, the combination of an engine having a surface condenser with a
tubular boiler, provided with a fan or pump or similar mechanical means of
producing artificial draught in its furnace or furnaces, as herein-before
described.
Third, the combination of a steam engine having a surface condenser with
a tubular boiler having an inverted or hanging bridge or bridges beyond
or behind the ordinary bridge or bridges in its furnace or furnaces and
provided with a fan or other means of producing artificial draught, as
herein-before described.
Fourth, supplying the waste of distilled water in marine engines working
with surface condensers by means of an auxiliary engine driven by steam
from an auxiliary boiler, or from a separate compartment of the main boiler,
and which exhausts into the main boiler or into the main compartment
of the same, which supplies steam to the main engines, as herein-before
described.
Fifth, the mode of heating the cylinders or pistons, or both, and supplying
the waste of distilled water in marine engines working with surface
condensers by introducing steam into the steam jackets or heaters from an
auxiliary boiler or from a separate compartment of the main boiler, which
steam or the water condensed from it is afterwards conducted into the main
boiler or into the main compartment of the same, which supplies steam to
the said engines, as herein-before described.
Sixth, the mode of introducing heaters into the cylinders or on or in
the pistons of steam engines, as herein-before described in reference to
Figure 3.
Seventh, the mode of producing a circulation of steam through the jacket

page_text: or heaters of steam engine cylinders and pistons, by means of a pump or
pumps, as herein-before described.
Eighth, the combination of a tubular boiler having mechanical means of
producing artificial draught, with an engine having a surface condenser, and
having a jacket or jackets, or a heater or heaters for heating the cylinder
or cylinders, or piston or pistons, or both, as herein-before described.
Ninth, the combination of a steam engine having a surface condenser and
a cylinder or cylinders, provided with a steam jacket or jackets, or a heater
or heaters, as herein-before described, with a main boiler or boilers, provided
with mechanical means for producing artificial draught, and an auxiliary boiler
or boilers, or compartment or compartments of the main boiler or boilers,
which auxiliary boiler or boilers or compartment or compartments supply the
steam jacket or jackets or heater or heaters, as herein-before described.
Tenth, the application of the syphon well or wells to marine engines, as
herein-before described.
In witness whereof, I, the said Lavington Evans Fletcher, have hereunto
set my hand and seal, this Seventeenth day of September, in the year
of our Lord One thousand eight hundred and fifty-eight.
20 Witness,
LAVINGTON E. FLETCHER. (L.s.)
CHARLES CowPER,
20, Southampton Buildings, Chancery Lane,
London.