IMPROVEMENTS IN PROPELLING VESSELS; ALSO IMPROVEMENTS IN STEAM ENGINES, AND IN THE METHOD OR METHODS OF WORKING SOME PARTS THEREOF, SOME OF WHICH IMPROVEMENTS ARE APPLICABLE TO OTHER USEFUL PURPOSES
Year: 1836

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SAMUEL
HALL, of Basford, in the County of Nottingham, Civil Engineer, sead
greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Twenty-fourth day of June, in the sixth year of His
reign, did, for Himself, His heirs and successors, give and grant unto me, the
said Samuel Hall, His especial licence, full power, sole privilege and authority,
that I, the said Samuel Hall, my exors, adññiors, and assigns, or such others
as I, the said Samuel Hall, my exors, adññiors, 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 lawfully might make, use, exercise,
and vend, within England, Wales, and the Town of Berwick upon Tweed, and
also in all His Majesty's Colonies and Plantations abroad, my Invention of
"IMPROVEMENTS IN PROPELLING VESSELS; ALSO IMPROVEMENTS IN STEAM ENGINES,
AND IN THE METHOD OR METHODS OF WORKING SOME PARTS THEREOF, SOME OF WHICH
IMPROVEMENTS ARE APPLICABLE TO OTHER USEFUL PURPOSES;" in which said Letters
Patent is contained a proviso that I, the said Samuel Hall, shall cause a
particular description of the nature of my said Invention, and in what
manner the same is to be performed, to be inrolled in His said Majesty's
High Court of Chancery within six calendar months next and immediately
after the date of the said in part recited Letters Patent, as in and by the same,
reference being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, 1, the sand
Samuel Hall, do hereby declare that the nature of my Inventions, and the
manner in which the same are to be performed, are fully described and ascer-
tained in and by the following description thereof, reference being had to the
Drawings hereunto annexed, and to the figures and letters marked thereon
(that is to say):-
The object of my Invention as regards the propelling of vessels is to reduce
the tremulous motion of steam vessels, and decrease the back water caused
by common paddle wheels, without impairing the propelling power.
The manner in which this part of my Invention is to be performed is shewn
at Figures 1 and 2 of the annexed Drawing, and consists of a mode of affixing
the paddle boards to the paddle wheels, whereby, during one half of the revo-
lution of each paddle wheel, the water shall be put in motion in one direction,
iu
and by the other half of the revolution the water shall be struct and put
motion in another direction, so that the paddle boards shall be constantly
striking in an oblique direction against currents of water produced in different
directions by the paddle boards themselves; this I effect by placing about half
of the number of the paddle boards on the wheels in a diagonal position, so as
not to enter the water in a line parallel with its surface, but diagonally in one
direction, and by placing the other half of the number of the paddle boards
so that they shall enter the water in the reverse diagonal direction, as shown
by the annexed Drawings. Figure 1 is a side elevation, and Figure 2 an
end elevation, of a paddle wheel, having my improvement applied; from these
Figures it will be seen that the paddle boards, instead of standing at right
angles to the rims of the wheels, and parallel to the axis of the wheel, as in
wheels of the ordinary construction, are placed obliquely to the rims and to the
axis of the wheel. The angle which the paddle boards should form with the
axis may vary from thirty degrees to sixty degrees, but I prefer the mean of
these two angles, videlicet, an angle of forty-five degrees. I have already
stated, and it will be seen by the Figures 1 and 2, that the paddle boards do
not all incline the same way, but that half of the number incline in one direc-
tion and the other half in the opposite direction. In large paddle wheels the
oblique positions of the paddle boards may vary four times in the revolution
of the paddle wheels instead of twice.
As relates to my improvements in propelling vessels, I do not lay claim to
the use of paddle boards entering the water in a diagonal or feathering direction,
that not being now; but I claim as my Invention, the making of about one
half of them to enter the water in one diagonal direction, and the other half
to enter it in the reverse diagonal direction; or, in large paddle wheels, in

page_text: making the boards to change their direction, of entering into the water four
times during the revolution of the paddle wheels instead of twice; thus, about
a fourth part of the paddle boards may enter the water in one diagonal direc-
tion, the next fourth part or thereabouts may enter it in the other diagonal
direction, and so on, changing their direction four times, as above stated, during
one revolution of the paddle wheels, instead of twice.
My present improvements on steam engines are six in number. My first
consists in apparatus to effect the combustion of fuel more perfectly than has
hitherto been done, by reducing (if not altogether preventing) the escape of
inflammable gases, carbon, or other combustible matters up the chimneys of
steam engine and other furnaces in the form of smoke, or without undergoing
the processes of inflammation and combustion.
The apparatus I employ for effecting this purpose introduces a quantity of
heated atmospheric air at the entrance of the fire-place (when it is a long fire-
place) for it to pass over the fire from one. end to the other, to inflame and
effect the combustion of any unignited inflammable gases, carbon, and other
combustible matters as they are generated and liberated from the fuel, and
before they arive in the form of smoke at the chimney, or perhaps even at the
flues leading thereto, or at the bridges of the furnaces; at the same time the
quantity of air admitted into the ash-pit and underneath the fire may be
reduced; for as the oxygen of the atmosphere that is introduced underneath
the fire is for the most part converted into, carbonic acid, which is calculated
to extinguish the flame of inflammable matters instead of supporting their
combustion, no more air should be admitted underneath the fuel than is found
necessary, but as much heated air should be passed above it as can be used to
advantage. In an engine of mine of ten-horse power, which had an opening
into the ash-pit underneath the fire-bars of three feet three inches wide and
twelve inches deep, equal to four hundred and sixty-eight square inches, I have
reduced it to one-third of that area. Experience, however, will shew the most
proper quantities of air to be introduced below the fuel, which is easily
regulated by any suitable means. When the fire-place is not a long one (as
in locomotive engine and other similar boilers), I introduce the heated air all
around the fire, or at as many sides of the fire-place as is convenient, so as to
effect, as before mentioned, the combustion of the carbon, inflammable gases,
or other combustible matters as they are generated by the combustion of the
fuel and liberated therefrom.
The above-mentioned supply of heated air I obtain by a means of applying
the heat of the flame or gases which escape up the chimney to increase the
temperature of a quantity of air which is introduced, as above mentioned, into

page_text: the fire-place and above the fire, to effect the ignition and combustion of the
combustible matters aforesaid. The manner of doing this is shewn by the
Drawings.
Figures 3, 4, and 5 represent the apparatus for supplying heated air according
to my Invention as applied to a marine steam engine boiler; Figure 3 being a
longitudinal section of the apparatus and of a portion of a boiler; Figure 4
is a front elevation; and Figure 5, a plan. a is the chimney; b, b, are two
plates of cast iron or other suitable material inserted in the chimney at any
convenient distance apart, which is regulated by the length of the pipes c, c, as
hereafter described; I place them at a distance of ten feet from each other.
The lower plate should be as low down in the chimney as can conveniently be:
c, c, are a series of metalic pipes of any convenient diameter; I use them of
from seven to nine inches in diameter. They are open at each end, and are
inserted into holes in the plates b, b, and are supported in their situation by angle
irons. d, d, are apertures in the circumference of the chimney, as near as may
be to the top of the pipes and the under side of the upper plate b, b; or there
may be added a funnel, as applied to the locomotive steam engine, shewn in
Figure 6.
c, e, Figure 3, are similar apertures in the chimney, just above the
lower plate b, b, which open into and communicate with a casing f, f, sur-
rounding the foot of the chimney. 9, 9, are channels leading from the casing
ff, to the apertures h, h, in the front of the fire-place and above the fire doors.
The external atmospheric air enters at the apertures d, d, and pass down the
chimney on the outside of the pipes c, c, and then passes out at the apertures
e, e, into the casing f, f, and from thence along the channels g. 9, to the
apertures h, h; thus, the air by its passage over the heated surface of the tubes
c, c, and of the top and front of the boiler becomes considerably heated, so as
to enter the fire-places at h, h, in front of the fire at a temperature sufficiently
elevated to cause by its passage over the fuel the ignition and combustion of
the greater part, if not the whole, of the combustible matter which usually
passes off to the chimney_in_the_form.of-smoke.-
Figures 6, 7, and 8 represent my apparatus as applied to the boiler of a
locomotive steam engine. Figure 6 is a longitudinal section of the engine
taken through the centre; Figure 7 is a transverse section, taken, as
shewn by dotted lines, from a to a; Figure 8 is another transverse section
taken from y, y. a, a, is a casing of thin iron or other suitable material
enclosing the chimney, and leaving a space between them (i.e. between the
chimney and the casing, which is closed at the top,) of about an inch wide.
b; b, is a casing to a part of the boiler. The two casings of the chimney
and of the boiler are united together, so as to form one continued casing from

page_text: the top of the chimney to the fire-place. c, c, c, are short tubes all around
the fire-place, connecting the casing with the fire-place; and above the
fire bars d, e, are two funnels, attached to apertures at the top of the casing
round the chimney. When the apparatus is in operation the external air enters
at one of these funnels, videlicet, at d when the engine is proceeding in one
direction, and ate when it moves in the other direction. There are two division
plates extending from the top of the casing to a little below the apertures d, d,
as shewn by dotted lines, in the casing round the chimney.
The air strikes against these plates, and then proceeds down the space
between the casing and the chimney, and thence over the boiler, between it
and the casing surrounding it, whence it passes through the tubes c, c, c, into
the fire-place just above, and on all sides of the burning fuel.
If the air by descending in contact with the chimney be heated beyond the
tempetature of the steam within the boiler, a portion of heat will be given out
by the air to the boiler during its passage along it to the fire-place; but if the
air be not heated to the temperature of the steam, then the boiler will give
out a portion of heat to the air, and cause it to be of sufficient temperature to
effect the object of my Patent.
In some cases, the combustion of the smoke, as aforesaid, may be effected
by the heat derived by the air passing over the boiler only; and this process is
not attended with so great a disadvantage as might be supposed, for the heat
taken from the top of the boiler is restored underneath it, to which will be
added the heat arising from the more complete combustion of the inflammable
gases and other matters constituting smoke; where, therefore, other means of
heating the air cannot be conveniently adopted, this will be found a process
capable of effecting the combustion of smoke; instead of a casing round the
chimnies of locomotive engines for heating, the air pipes may be fixed within
such chimnies in the way they are applied to marine engines, as shewn at
Figure 3.
Figures 9 and 10 represent my apparatus as applied to a land steam
engine; Figure 9 being a longitudinal section of it, and Figure 10 a
horizontal section of the chimney and the pipes within it. a is the chimney;
b, b, are two plates of cast iron, similar to those in the chimney of the marine
engine boiler, shewn by Figures 3, 4, and 5, except that they are of a
quadrangular form to suit the shape of the chimney; they are supported
by grooves cut in the sides of the chimney into which they are inserted. c, c,
are pipes, which are also of a quadrangular form to suit the chimney, or
they may be round; they are fixed in the plates b, b, in the same way as has
been shewn of the pipes in the chimney of the marine boiler. d, d, are

page_text: apertures in the chimney, for the admission of atmospheric air to pass down it
on the outside of and among the pipes c, c. c is an opening in the lower part of
the chimney and in the side next to the boiler; f, f, is an arch of brickwork or
other suitable material over the boiler, leaving a space g, g, between them,
which is connected with the opening e in the chimney; h, is a long narrow
opening, connecting the space g, g, with the upper part of the fire-place, close
to and above the fire door; across this opening may be placed a slide, to
regulate the quantity of heated air admitted into the fire-place and above the
fire. It is obvious that the operation of this apparatus will be the same as that
described in Figures 3, 4, and 5, videlicet, the atmospheric air will pass down
the chimney a, on the outside of and among the pipes c, c, through the open-
ing c, and along the space g, g, whence it will pass through the opening h
into the fire-place.
Having thus described the best means for carring out my Invention, I
would remark, that on enquiry and examination I have learnt that attempts of
various kinds have been made (for some of which Patents have been obtained)
to effect more perfectly the combustion of the fuel and of the smoke arising
therefrom in the fires of steam boilers. In the first place, attempts have been
made, by introducing heated air in at the bridge or entrance of the flues
leading to the chimney, and consequently beyond the fire, such air being
heated by a separate fire, or by the furnace itself, or by the flues of the
boiler. Secondly, similar attempts have been made, by introducing heated
air at the bridge and beyond the fire, such air being heated by causing
it to pass through the insides of tortuous or bent pipes placed within the
chimney, or in a chamber leading thereto, the air being forced through them
by blowing machinery, or by the draft of the fire through such tortuous or bent
pipes, or the air to be heated is drawn up among a series of pipes and down
from them through a large centrical main pipe. Other attempts have been
made, by passing air by blowing machinery through an extensive system of zig-
zag passages, interspersed with intermediate zig-zag smoke passages, through
which latter the heated gasses from the furnace are also passed by blowing
apparatus, to beat such air in the air passages, which heated air is sent under-
neath the fire into a closed ash-pit.
Having described various former attempts to effect more perfectly the
combustion of fuel and smoke, I now proceed to define the nature of my
Invention. It consists in heating a portion of atmospheric air by the methods
herein set forth by the Drawings and descriptions thereof, and the applica-
tion of such heated air at the entrance of the fire-place and above the fire bars
of steam engine furnaces in general, and in locomotive steam engines. Such

page_text: heated air may be admitted both above and below the bars, the ash-pit being
closed. My claims respecting this part of my Invention I shall make in
numerical order.
First, I claim the threefold combination of, firstly, heating air by means of
pipes, as herein described, placed in a chimney, or in a chamber leading thereto,
or by a case surrounding the chimney; secondly, the leading of the air
thence through a casing over the boiler; and, thirdly, the causing of it then to
proceed to and enter at or over the fire doors at one end of the fire-place, and
to pass over the whole length of the fire on its way to the bridge or flues of
furnaces with open ash-pits.
Second, I claim the twofold combination of heating air by means of pipes,
as herein described, or a casing round the chimney, as mentioned in my first
claim, without passing it over the boiler, but conveying it by pipes or flues
direct from the outsides of the above-mentioned pipes or from the casing
round the chimney into fire-places with open ash-pits at or over the fire-doors,
as described in my first claim.
.
Third, I claim the twofold combination of heating air by passing it over the
boilers only, and without using the pipes placed in the chimney or casing round
it, and causing the air to enter, as before described, into fire-places with open
ash-pits.
Fourth, for locomotive engines, I claim the combined modes of heating air
as described in my first claim respecting my first improvement: on steam
engines; but the air so heated may be introduced either above the fire-bars,
the ash-pit being kept open, or it may be admitted both above and below the
bars, the ash-pit being inclosed.
Fifth, for locomotive engines, I claim the mode of heating air, and con-
ducting it to the fire as described in my second claim respecting my first
improvement on steam engines, the air so heated being applied in either of the
modes described in my fourth claim.
Sixth, for locomotive engines, I claim the mode of heating air as described
in my third claim respecting my first improvement, on steam engines, the air
so heated being applied in either of the modes described in my fourth claim.
Seventh, 1 claim for the heating of air, for the purposes described in this
Patent, the use of a number of straight pipes fixed in two plates of iron, or
other suitable material, and placed in a chimney or in a chamber leading
thereto, such chimney or chamber forming the casing for enclosing such pipes,
the atmospheric air which is to be heated to enter the casing containing the
pipes, and proceed over then in one straightforward direction, as described in
this Specification, without taking one or more zig-zag courses; for any changes

page_text: in the direction of the current of air will prevent so ample a supply thereof as is
attained by the straightforward direction, above described, unless the assistance
of a blowing apparatus or other mechanical means be resorted to.
My second improvement on steam engines consists in a means of preserving
the tubes, constituting the flues of locomotive steam engines and other tubular
boilers, from the rapid wear and tear to which they are now subjected from
the action of the fire.
This second improvement on steam engines I effect by putting thin, moveable
linings of copper, brass, or other suitable metal within the tubes of the boilers.
These linings should when cold fit the boiler tubes as closely as possible, id est,
as closely as they can with ease be driven in and out. They may either be
brazed, and form a thin tube; or they may be unbrazed, and have the edges
which meet together either flat, so as to abut against each other, or they may be
bevelled; so as to overlap each other, as by practice may be found to be the best.
If the linings fit the boiler tubes well when cold, they will when heated fit so
tightly as to make the lining and tube press together, so as to be nearly if not
altogether equal to a solid tube, of the united thicknesses of the two, for the
purposes of transmitting heat from the fire to the water in the boiler, and the
linings will preserve the tubes which are in contact with the water from wear
and tear. a, Figure 11, represents an end view of one of the boiler tubes of
a locomotive engine. c is the lining, which should project a little out of the
tube (at the end most distant from the fire), in order that it may be easily
<driven out when required to be replaced by a new lining.
My claim, as relates to this second improvement in steam engines, consists
in the application of moveable linings to the tubes or pipes constituting the
flues of the boilers, to protect them from the action of the fire, whereby the
tubes or pipes will endure for a greatly increased length of time, and the
linings can easily be replaced when requisite, and they are the subject of wear
and tear instead of the pipes themselves.
My third improvement on steam engines consists in improvements in the
apparatus for distilling in vacuo the requisite quantity of water for supplying
any waste of pure water that may take place in the boilers during the working"
of the engines, as described in the Specification of my Patent of Thirteenth
February, One thousand eight hundred and thirty-four.
This third improvement on steam engines consists of a distilling apparatus,
occupying but very little room, which is capable of distilling a much greater
quantity of water than the apparatus described in my aforesaid Patent, unless
it is exceedingly large. This consists in giving a much greater extent of
metallic surface in a small compass for the transmission of heat from the

page_text: water and steam in the boilers to the water to be distilled, which is
effected by a series of pipes, similar to those of the condensing appa-
ratus described in my Patent aforesaid; but the pipes for the distilling
apparatus I prefer of a considerably greater diameter, as shewn in the
Drawings: Figure 12 represents a longitudinal section of my improved dis-
tilling apparatus. a, a, is a metallic box, forming the upper chamber of the
apparatus; and b, b, is a smaller box, suspended from the former by rods c, c,
at the angles of the boxes. d, d, are a series of copper pipes, of about one
inch internal diameter, open at each end, and passing through holes in
the plate of the box a, a, and also through the holes in the plate of the
box b, b. These holes are enlarged to receive a tape washer, which is
screwed into close contact with the copper pipes by means of a brass ring or
ferrule, so as to form a steam and water tight joint, in the same manner that
the joints of the pipes of the condensers are made, as described in my former
Patent. c is a pipe for supplying the still with water, and f is a tap attached
to it; 7 is a box containing a valve for the admission of the supply water,
regulated by the float h; k is a pipe by which the steam from the still passes
to the upper chamber of the condenser; it has a tap at 7. m is a pipe
(attached to a tap n) by which the foul water and impurities deposited in the
course of distillation are removed, which is effected by closing the taps f and
I and opening n and o, which latter admits the steam from the boiler by the
pipe p into the chamber a, a, and the pressure of the steam drives out the foul
water by the pipe m. In the Drawing, the copper pipes and the box b, b, of
the apparatus are shewn inserted in the boiler, but the whole of the apparatus
may be placed on the outside of the boiler if the pipes be surrounded by or
enclosed in a casing connected by pipes at the top and bottom with the
boiler.
My claim, as relates to my third improvement on steam engines, consists in
the application or use of tubes or other proper means of presenting in a small
compass an extensive surface of metallic plate, for transmitting heat from
boiling water or steam to water intended for the purpose of distillation in
vacuo, for the purpose described in my Patent of Thirteenth February, One
thousand eight hundred and thirty-four.
My fourth improvement on steam engines consists in a means of or appa-
ratus for supplying in some cases such waste of pure water as aforesaid by
distillation, without the assistance of a vacuum.
This fourth improvement on steam engines consists in a means of supplying
such waste of water to boilers, as has been already mentioned, without the
assistance of a vacuum, by making use of one compartment of a boiler, when

page_text: it consists of several compartments, for receiving the salt or other impure water
for distillation, or the making use of a small separate boiler (which may also
be otherwise rendered useful) for that purpose, which in large vessels and long
voyages may be found desirable. If a compartment of the boiler be used for
distillation, it must be so separated by any proper means from the other
compartments, that no admixture of the impure water in the former with the
pure water in the latter shall take place. If a small separate boiler be
employed for distillation, the steam generated by it should be caused to enter
the steam pipe which conveys the steam from the boilers to the working
cylinders of the engines, by which means it will be reduced to water on its
arrival at the condenser.
My claim, as relates to my fourth improvement on steam engines, consists
in the means I have pointed out of supplying distilled water without the aid
of a vacuum to the boilers of such engines as have the apparatus and improve-
ments as described in my Patent of the Thirteenth day of February, One
thousand eight hundred and thirty-four, applied to them.
My fifth improvement on steam engines consists in a means of supplying in
some cases, i.e. where the impurities of water are such as are separable by
filtration, not only the above-mentioned waste of pure water, but in some cases
the whole of the water required for the supply of steam engine boilers.
This fifth improvement on steam engines consists in the use of a filtering
apparatus which I have devised, of a peculiar description, one of its peculiari-
ties and essential qualities being, that it is so small and occupies so little room
that the process of filtration even for large steam engine boilers may be con-
veniently carried on in the engine rooms of marine steam engines. This
apparatus is shewn by Figures 13, 14, 15, and 16. Figure 13 is a longi-
tudinal section of the apparatus; Figure 14 is a transverse section; Figure 15
is a plan in section, taken from a to r, as shewn by the dotted lines; and
Figure 16 is a front elevation. a, a, is the chamber for containing the proper
filtering material, whether it be sand, spunges, cloth, or other suitable material.
I use woollen cloth or calico. b, b, is a chamber underneath chamber a, a,
and is separated from it by a metallic plate full of small holes; d is a round
opening, to conduct the stream of impure water for filtration along the flat
channel e; f is an opening similar to d, and g a flat channel similar to c,
for the escape of such part of the impure water as does not pass through
the filtering media; these openings d and f, and channels and g, arc
cast to and form a part of the box or chamber c, c. h, h, are two rollers,
furnished with handles j, j, for turning them; a quantity of calico or other
proper material is wrapped on these rollers, to pass backward and forward

page_text: from one roller to the other underneath the channels e and g, and of course
between the water to be filtered and the filtering medium in the chamber
a, a. k, k, are two conducting rollers; to guide the calico in a straight line
between the channels e and g and the filtering medium. m is a circular
brush, provided with a rigger or pulley, for brushing off the mud that
would otherwise be deposited on the calico on its passage underneath the
stream of dirty water during the process of filtration. n is a pipe to connect
chamber b, b, to the condenser or the bottom of the air pump, for drawing the
water through the filtering medium and passing it forward to the boilers; or
a pump of a proper description may be applied to the pipe n, to produce a
vacuum and force the filtered water to the boilers.
My claim, as relates to my fifth improvement, consists in the supplying of
steam engine boilers wholly or in part with filtered water, by means of that
desideratum a filter, sufficiently small to be used in the engine rooms of marine
steam engines.
Sixth, an improvement in the apparatus for equalizing or regulating the
entrance of the steam from the working cylinders into the pipes of the con-
densers, as described in my said Patent of the Thirteenth February, One
thousand eight hundred and thirty-four.
This sixth improvement on steam engines, videlicet, the better distribution
of the steam into the condensing pipes, consists in having, in addition to the
distributing plate, described in my said Patent of Thirteenth February, One
thousand eight hundred and thirty-four, other plates to conduct the steam to
the distributing plate from the working cylinder, in such a way as to cause it
to be more equally divided when it arrives at such distributing plate than is
the case without the use of such conducting plates. This apparatus is shewn
in Figure 17, which is a transverse section of the upper part of a condenser,
as described in my Patent of Thirteenth February, One thousand eight hundred
and thirty-four. a is the aperture by which the steam from the working
cylinder of the engine enters the upper chamber of the condenser; b, b, b, is the
distributing plate, as shewn in the above-mentioned Patent; c, c, c, are three
conducting plates, attached to the distributing plate, for conducting the steami
in as equally divided quantities as possible from the aperture a to the dis-
tributing plate; the ends of the conducting plates abut up to the aperture a,
dividing the steam as it passes through it into four quantities, as nearly equal
as possible, and conducting it to the distributing plate in the same equal
quantities, by the conducting plates being so attached to the distributing plate
as to divide it into four equal parts. Thus it will be evident that each fourth

page_text: part of the steam from the working cylinder is brought over about a fourth
part of the condensing pipes.
There are a considerable number of small holes in the flat parts of the con-
ducting plates, to prevent their getting out of shape by any inequality that may
possibly take place in the pressure of the steam between them. These holes
will interfere but very little with the conducting power of the plates. There
are also small pillars attached to each conducting plate, as well as to the
distributing plate, to prevent their vibrating too much or bending.
My claim, as relates to my sixth improvement on steam engines, consists in
dividing the steam as nearly as possible into a number of equal parts as it
issues from the working cylinder, and in conducting it, so as to enter as
nearly as possible into corresponding equal proportions of the pipes of the
condenser.
My improvements in the modus operandi of the apparatus described in
my aforesaid Patent of the Thirteenth day of February, One thousand eight
hundred and thirty-four, consist in keeping some parts of the engines in good
and efficient order, and in relieving the engines in some cases from water
at starting, and preventing on those occasions any waste of pure water. The
first improvement in the modus operandi of the apparatus described in
my aforesaid Patent consists in the following method of cleansing the con-
densing pipes, if it be ever from accidental circumstances required. In order
to effect this, a stream of an alkaline lixivium, or of a solution of soap, or of
a mixture of both, must be drawn into the aperture leading from the working
cylinder to the top chamber of the condenser while the engine is moving
as slowly as possible; this stream of liquid must be prevented from going into
the boiler, and must be discharged from the engine by a cock, fixed for that
purpose at any convenient place between the discharge valve of the air
pump and-the-boiler. The stream of alkaline or saponaccous fluid must
b: continued so long as that after passing-through the condenser it shall no
longer continue to come away in a dirty state from the above-mentioned-cock,
and the admission of the alkaline or saponaceous fluid may then be discon-
tinued; when that is donc the engine must be continued working, without
any water passing into the boiler, until the water resulting from the condensa-
tion of the steam has washed away all the saponaceous or alkaline matter;
when that is effected the water may in the usual manner be sent from the
condensers by the air pump into the boilers. This process I have devised and
secured by the present Letters Patent to meet particular cases and not for
general use. In the first place, it has so happened that partics unknown to me

page_text: put a quantity of horsedung (or other filth) into the boilers of a pair of engines
to which my improvements were applied, which fermented and passed through
the working cylinders and into the condensers, of course fouling the pipes.
Now, by the above-mentioned operation the effects of similar mischief is
immediately removed, and the pipes are made as perfectly clean as ever. In
the second place, there are some persons who doubt whether the pipes will keep
clean, notwithstanding the fact that nothing but steam generated from pure
distilled water passes into them; I have therefore devised this process to remove
their doubts. The second improvement in the modus operandi of the said
apparatus consists in the application of a pump to the lowest part of the air
pump of the engine, to draw away any water that may accumulate in either it
or the condenser and to send it into the boiler.
My claims, as relate to the improvements in the modus operandi of engines
with my improvements, consist in the means I have pointed out, first, of cleaning
the condensing pipes; and, secondly, in the means I have described of relieving
the engines from water at starting.
The other useful purposes to which some of my improvements are applicable
are the heating, boiling, and evaporating of all descriptions of liquids, and I
hereby claim the application of my Invention for the more effectual combustion
of fuel and smoke to all furnaces employed for such purposes.
In witness whereof, I, the said Samuel Hall, have hereunto set my hand
and scal, this Twenty-fourth day of December, in the year of our
Lord One thousand eight hundred and thirty-six.