Year: 1898

page_text: I, WALTER CARR, 5, Earlham Road, Bowes Park, Wood Green, N., Engineer,
do hereby declare the nature of this invention to be as follows:-
This invention refers to a method of propelling ships boats and other craft by
means of atmospheric air, or other suitable gas or gases
In accordance with this invention the hull or body of vessel would vary in
shape with the requirements of the service for which such vessel was intended.
Thus
For extreme shallow draught where maximum. displacement on given length
& breadth is required, the hull would be rectangular in transverse vertical section,
throughout its entire length the sides being vertical & parallel & the bottom flat.
For the greater portion of its length, the bottom, or floor is flat & horizontal
both longitudinally & transversely, but for a short distance at either end it, while
remaining flat transversly, rises, either abruptly in a flat plane, or by a suitable
curve, or curves, to some distance above the water line. The vertical plates
forming the sides of hull do not rise in conformity with the bottom but may
retain their full depth, i.e. their lower edges may continue horizontal, to the end
of the vessel, or even beyond, the extreme corners only being rounded off, which
rounding off however may, in some cases he so considerable, as to constitute a
continuous curve from the point where the bottom begins to rise.
In the case of a vessel intended to proceed mainly in one direction i.e. a'head,
the upward slope of the bottom at the, stern or propelling end, is comparatively
steep, the rise preferably taking the form of a compound curve specially adapted
to afford space for a stratum of air which is emitted from a narrow rectangular
horizontal slot or opening extending partly or wholly across the vessels bottom
at or about the point where the upward slope commences.
At the opposite or bow end the rise of floor is much more gradual & the corre-
sponding emission aperture is situated at a somewhat higher level, the downward
extension of the side plates being also considerably modified both as to form &
extent, the object being to obtain greater arresting, as distinguished from pro-
pelling effeciency.
The emission apertures at both bow & stern are divided into any convenient
number of separate openings by means of plates or webs fitted vertically within
said apertures & extending thence longitudinally along the under surface of
curved portion of bottom & more or less conforming to the already described side
plate extensions, & with them forming a series of channels which serve to main-
tain the position & direction of the propelling air stratum, & to provide for
steering & manevring generally.
The emission or discharge apertures to which reference has been made open
out of a suitably formed chamber extending, as in the case of said apertures
partly, or wholly across the vessel. This chamber is fitted with a central vertical
diaphragm or plate, attached to the floor or bottom, & extending to some distance

page_text: above water line, but not touching top, or cover of said chamber, the arrangement
having for its object the exclusion of the external water from the air mains, or
conduits when, as is generally the case, such mains or conduits are disposed
below the water line.
In addition to the central diaphragm, this intercepting appliance is further
provided with other vertical plates at right angles to the main one. These, plates
are however attached to both top, & bottom of chamber & extending outward
through the emission apertures, become identical with, & discharge the same
functions as, the webs or keels before mentioned, as attached to the under surface
of stern. In some cases this intercepting chamber may be dispensed with.
The foregoing description applies to the forward or bow end with the exception
that, as already explained, the forward emission apertures are situated at a higher
level, & the upward slope of bottom is more gradual.
When the vessel is required to move with equal facility in either direction,
both ends are similarly formed, the shape being practically, a compromise between
that of the bow & stern already described.
Where greater draught of water is admissible, & speed a consideration, the
shape of the sides may conform more nearly to that of ordinary vessels, the middle
body retaining its rectangular section as explained.
Or again, the bow may be of normal form, the stern only being of the special
form described, or the entire hull may be quite normal, in which case the emission
apertures are disposed longitudinally close to the keel, at a suitable depth
distance from either end, the action of the air being further assisted if desired by
the addition of bilge plates or keels, such as are in present use to prevent
excessive rolling..
The necessary air may be supplied by any of the usual forms of air com-
pressing machinery such as pumps, fans, etc., but in most cases it is preferred to
use a special form of steam jet apparatus.
This may consist of a single steam jet with an appropriate receiving air cone
or cones, or there may be a group of jets delivering into a suitably arranged series
of cones, or each individual jet may deliver into its own seperate cone or series of
cones. Where a number of jets are employed, some of them may be arranged
to act as auxiliaries or feeders, i.e. to supply air already in motion to the main
driving jet or jets.
The jets may be of the solid or the annular type, or a combination of both.
The receiving air cones, when more than one are used, are disposed in a
particular progressive series, with the object of utilizing as far as possible,
the expansive property of the steam, the arrangement corresponding to some
extent, with the successive cylinders in a multiple steam engine.
One or more of these cones may be water jacketed, with the object of partially
condensing the steam, & so reducing the volume of the combined steam & air
current, & also heating the feed water, which may be passed through said
jacket, & thereby freed, to some extent, from salts in solution, & suspended
matter.
The cooling effect may be further increased, by the application of some suit-
able porous material, asbestos cloth, or fibre, slag wool, etc., to the exterior
surfaces of said jackets, & allowing water to percolate through such porous
material, or the jackets may be dispensed with, & the porous material applied
direct to the outside of the cone or cones.
Great importance is attached to both internal & external shape of jets &
cones, which are formed with special curves, offering the minimum resistance to
the steam or the combined steam & air. The combined steam & air from the jet
apparatus passes to a distributing valve which preferably, consists of a fixed
circular plate or disc, having suitably formed radial openings, communicating
with the various air trunks fore & aft. Super-imposed on this fixed plate, is a
revolving one, having similar openings which, according to its, (the revolving
plate's,) position relative to the fixed plate, allows the combined steam & air

page_text: pass into either, or any of the air trunks for the purpose of reversing, steering,
stopping, & manevring generally. In certain cases, two or more revolving plates
or segments of plates may be used & also a relief valve. The plates described
are enclosed in a suitably formed chamber, & are actuated by any convenient
mechanical device. In large sizes by cog or worm wheels in combination with
appropriate levers, or levers only may be used espically, in the case of small
powers. This valve may also be cylindrical in form, with narrow longitudinal
slots, or rectilenear, with transverse slots.
The air trunks or mains employed to convey the combined air & steam from
the distributing valve, to the intercepting or air lock chambers previously
described, & through them to the emission appertures, may be seperate tubes or
pipes, or may form structural portions of the vessels hull, in some cases con-
stituting a false or inner bottom, & further these passages or trunks, may if
desired, be adapted to act as condensers & feed water heaters.
Steam may be supplied by any of the usual forms of boilers employed for marine
purposes, but a particular form of generator is preferred, which consists essentially
of a series of coils of any suitable metal, of varying form & diameter.
The lower coil which forms the base, & supports & encloses the furnace, con-
sists of tubes preferably straight of relatively large diameter, which are intended
to heat and filter the feed water, & to deposit scale, for which purpose they may be
packed with suitable substances & provided with special means of access.
The succeeding coils may be of smaller diameter, & act more especially as
evaporators, & super-heaters, & deliver into a cylindrical chamber or steam drum,
from which the steam passes to the jet apparatus. To insure a steady stream, the
feed water is passed through an accumulator, or pressure equalizer, from which
it is delivered to the lowest series of coils, the circulation thus being of the
controlled type.
The whole of these coils constituting the boiler, or generator, or only a portion
thereof, may be enclosed in a sheet iron casing which may or may not be lined
with some suitable refractory material.
The above described construction of boiler forms the subject of another
application of even date herewith and I do not therefore herein lay claim to such
construction per se.
or vessels.
I, WALTER CARR, of 5, Earlham Road, Bowes Park, Wood Green, London, N.,
Engineer, do hereby declare the nature of this invention and in what manner
the same is to be performed to be particularly described and ascertained in and
by the following statement:-
This invention relates to the pneumatic propulsion of vessels generally, whether
as the sole means of propulsion or as an emergency means of propulsion in sub-
stitution for the usual means of propulsion in case of need.
The invention relates more particularly to the propulsion of shallow draught
vessels for the navigation of rivers and canals, and as applied to such vessels it
consists of a combination or system comprising a hull having a bow and stern
of special form in transverse and longitudinal section; air emission passages of
peculiar form or arrangement terminating in orifices extending as nearly as
possible across the full breadth of the bow and stern respectively; means of

page_text: distributing the air uniformly across the full breadth of the propelling surface
and of preserving such uniformity of distribution during its ascending passage
along the propelling surface of the hull; means of conveying the air either to
the bow or stern and of controlling the distribution of the air either to the stern
or the bow emission orifice, or to a part of the one or of the other orifice for
purposes of forward or backward propulsion and steering; induction steam and
air jet apparatus comprising jet nozzles and receiving cones of special construction
and so arranged as to be surrounded by the hot gases of combustion and draw in
part the supply of air through the furnace and in part otherwise, whereby to
maintain the required rate of combustion and to effect the most economical com-
pression of the air; a steam generator or generators of special construction for the
economical production of steam at very high pressure, and means of reducing
the steam pressure at a point between the generator and a superheater whereby
is supplied the heat necessary to maintain the temperature of the steam or
even to increase it notwithstanding the loss of sensible heat incidental to the
reduction of pressure; and a special construction of internal furnace whereby the
fire grate is extended up the sides of the furnace which therefore becomes effective
as grate area permitting the access of air to the fuel for supporting combustion
besides preventing contact of the incandescent fuel with the generator tubes
enclosing the furnace.
Reference is to be had to the accompanying drawings forming part of this
specification which illustrate the preferred form in which my invention may
be embodied for the purposes of shallow draught navigation and wherein Figure 1
shows a longitudinal vertical section of the after portion of a shallow draught
vessel and a part sectional elevation of the jet and distributing apparatus.
Figure 2 is a transverse vertical section looking aft, one of the generators (of
which it is preferred to use a pair) being represented in section. Figure 3 is a
diagrammatic half plan view of the bow and stern ends and of the middle portion
of the hull, portions being broken out. Figure 4 is a longitudinal vertical
section of the bow end. Figure 5 is a stern end view. Figure 6 is a
vertical section of the jet apparatus. Figure 7 is an inverted plan view
of the interrupted annular jet nozzle. Figure 8 shews an annular
cluster of conical nozzles surrounding a central nozzle and in combina-
tion with the same receiving cone. Figures 9 and .10 are end and
front elevations shewing diagrammatically the cones of a jet apparatus,
by which each segment of the steam jet issues as developed in the form of a flat
stream, the several streams being parallel and received in the same receiving
cone which is in this case rectangular in cross section. Figure 11 shews a single
similar nozzle and conc. Figure 12 is a vertical section of the superheater
shewing the device for reducing the pressure of the steam as it passes from the
generator to the superheater. Figure 13 shews the separate parts of the dis-
tributing valve. The same letters of reference indicate the same parts in all
the figures.
In accordance with this invention the hull or body of the vessel would vary
in shape with the requirements of the service for which such vessel was intended
but generally, and in particular for extremely shallow draught where the
maximum of displacement is required for given dimensions, the hull would be
of rectangular form in transverse section throughout its entire length the sides A
being vertical and parallel and the bottom. B flat. For the greater portion of
its length the bottom or floor B is horizontal both longitudinally and transversely
but while remaining flat transversely it rises gradually for a short distance at
either end either in the form of an inclined plane, or curved surface, to some
distance above the water line. The vertical sides A of the hull would however
preferably be continued of full depth to the stern end of the vessel or even
beyond or be made of slightly greater depth as shewn at a, the extreme corners
being rounded off more or less so that these downwardly projecting continuations
will always project so far below the inclined part of the bottom as, under all

page_text: circumstances, to prevent the lateral escape of the air and of the water acted on
by the air.
In the case of a vessel intended to proceed mainly ahead the upward slope of
the bottom at the stern is steeper than that at the bow, the rise preferably taking
the form of a compound curve especially adapted to afford space for the propelling
stratum of air. This air is emitted from a narrow slot or opening C extending
as nearly as possible wholly across the vessel's bottom B at or about the point
where the upward slope 1 commences. At the bow end the rise of the inclined
part of the bottom is much more gradual and the corresponding emission
aperture C is situated at a somewhat higher level than the aperture C the longi-
tudinal downwardly extending ribs or keels a being also considerably modified
both as to form and extent, the object being to obtain arresting, as distinguished
from propelling, efficiency. The emission apertures C C at bow and stern, and
the air channels leading thereto, are divided by any number of vertical webs c
which are continued longitudinally along the under surface of the inclined pro-
pelling surface of the bottom so as to form with the side extensions a, a series
of longitudinal channels which serve to maintain the position and direction of
the streams into which the propelling air stratum is thereby divided; and to
enable the propulsive effect to be applied towards the one or other side only of
the vessel so as to provide a means of steering and manœuvring generally, without
the use of rudders. The emission or discharge apertures Copen out of an
upcast and downcast channel F of corresponding breadth to said apertures, the
upcast and downcast channels being separated by a transverse vertical diaphragm
or plate f rising from the floor or bottom of the hull to some distance above the
water line so as to exclude the external water from the air mains or conduits
when, as is generally the case, such mains or conduits are disposed below the
water line, the dividing webs c before referred to dividing the upcast and down-
cast channel into a number of separate channels.
apparatus and channels are wholly above the water line the downcast portion
Where the air supplying
only of the channel would be employed.
The foregoing description applies also to the forward or bow end with the
exception that the deck plan form of the bow is more or less pointed and, as
already explained, the forward emission aperture or apertures would be situated
at a somewhat higher level than the rearward emission aperture and the upward
slope of the inclined bottom is more gradual than that at the stern as shewn.
When the vessel is required to be propelled indifferently in either direction
both ends are similarly formed in all respects the shape being practically a com-
promise between that of the bow and stern already described.
Where greater draught is admissible and speed is a consideration the sides,
instead of being straight and parallel, may be curved so as to conform more
nearly to the form of an ordinary vessel, the portion of the stern which is effective
for purposes of propulsion remaining of the rectangular form in cross-section as
above explained.
Where the form of the hull entirely follows the lines usually adopted, as
would be the case in applying the invention for use in case of emergency, in
substitution for the usual means of propulsion, the emission apertures for forward
propulsion would be disposed longitudinally close to and at either side of the
eel, at a point as low down as convenient in the "
which inclines upwardly towards the stern, the lateral escape of the air being
or that part of the hull
revented by bilge keels.
run
"
.
The distribution of air is controlled by a distributing valve consisting of a
otary adjustable plate or disc G and a rotary adjustable covering segment H
uperimposed upon the disc G which is itself seated upon a fixed plate
referably four or more radial openings i communicating with air trunks J Ji
having
xtending fore and aft between the double skin of the bottom of the hull or
therwise formed. The revolving disc G has openings g g', g³, (Figure 13) which
ccording to their position relatively to those of the fixed plate I and the super-

page_text: imposed covering segment H, allow the air to pass either to the stern or to the
bow, or to both the port side of the stern and the starboard side of the bow, or
vice-versa as may be required for the purpose of stopping, reversing, steering, and
manceuvring generally. The plates G H I constituting the distributing valve
are enclosed in a chamber K and are actuated by any convenient mechanical
device; in the example shewn the plates G and H are carried by concentric
vertical shafts G¹, H¹, and are adjusted by lever handles G², H². This valve may
however be a rectilinearly-moving slide valve with transverse slots. The air
trunks or mains J J¹ may be tubes or pipes or, as in the example shewn, may he
formed structurally between the double skin of the vessel's bottom. There would
generally be a pair of longitudinal trunks separated by a longitudinal central
web and divided transversely by a cross web into separate pairs J and J
leading respectively to the stern and bow orifices. I do not however limit myself
to a pair of trunks as there would generally be as many air trunks as there are
emission orifices and channels so as to enable the supply of air thereto to be
efficiently controlled.
In order to prevent steam blowing back through the furnaces should the
distribution valve happen to be placed in such position as to close the passage
of air in both fore and aft directions without the steam supply having to be
first cut off, a relief valve (not shewn) would be provided on the casing K in
gear with the distribution valve spindle so as to be automatically opened when
the distribution valve is in the position referred to.
In either case any suitable form of condensers (such as shewn at 1 for example)
would be placed in the air trunks for the purpose of condensing the steam con-
tained in the stream of air (and remaining uncondensed after passing through the
receiving cone of the air jet apparatus hereafter described) in order to recover
the water of condensation for use as feed water in the generator to which it is
supplied by usual means along with the water of condensation coming from the
receiving cone of the jet apparatus.
The air is supplied to the chamber K by a special form of steam jet apparatus
as shewn in Figures 1, 6, and 7. This consists of a main jet nozzle L in the
form of an annulus with segmental emission orifices separated by intervening
corresponding spaces the object of this form and arrangement being to expose as
large as possible a surface of contact of the steam to the air to be set in motion
thereby. This interrupted annular nozzle L is supplied with steam from a
chamber M connected with the generators, and with the nozzle L by tubes m
so as to admit air to the interior of the interrupted annular nozzle. In con-
nection with said chamber M is an auxiliary steam jet nozzle N which discharges
through a second larger nozzle P both of said nozzles being in axial alignment
with the main nozzle L which acts as a receiving cone therefor. The nozzle P
is in connection with the exhaust pipe from the engine Q (which works the feed
pump Q) and from any other auxiliary engines on the vessel, and the purpose
of the jet of live steam issuing from nozzle N or of exhaust steam issuing from
nozzle P (or of both if used conjointly) is to set in motion towards the interior
of the main nozzle a comparatively large body of air so as by preliminarily over-
coming the inertia of the air to increase the efficiency of the main jet. The
emission of steam through nozzle N is controlled by a valve n and the supply
of steam from the generator to the chamber M is controlled by the main stop
valve m¹. The main jet discharges into a main receiving cone R of the converging
and diverging form shewn, whose delivery end communicates with the distributing
chamber K, the cone being surrounded by a spirally divided water jacket r through
which a circulation of the feed water is maintained by the feed pump Q¹.
The object of cooling the cone R is to cool the mixed air and steam current
and thereby to reduce its volume in passing through the cone and so enable
the same quantity of air to pass through a cone having a throat of smaller
diameter and thereby increase the efficiency of the steam jets. The heat thus
abstracted would otherwise be lost on or before the emission of the air for purposes

page_text: of propulsion and therefore by cooling the cone efficiency is increased and the
heat is utilized for raising the temperature of the feed water.
Instead of a water jacket the cone may be enveloped with porous material
(such as fibre or asbestos cloth for instance) over which water may be allowed
5 to trickle.
The jet portion of the apparatus is enclosed within a chamber S which is an
extension of the smoke box of the generator furnaces so that the steam jet will
do its work in a highly heated medium, mainly hot products of combustion
whereby the requisite draught will be produced and the temperature of the jet
will be maintained whilst it is doing its work. The chamber S may also be con-
nected by air conduits (controlled by suitable dampers) with the cabins or any
other enclosed spaces requiring to be ventilated so that the air jet apparatus will
draw air from such enclosed spaces and so subserve the additional purpose of
ventilating the vessel. This chamber S is surmounted by a funnel or funnels T
controlled by dampers which would be opened at starting and more or less
closed when the jet apparatus is in action.
Instead of discharging the exhaust steam from the engine working the feed
pump and other auxiliary engines through the jet nozzle P, it may be discharged
into the ash-pit beneath the furnace with the object of promoting combustion
and increasing the draught and thereby assisting the action of the main jet
from nozzle L.
In Figure 8 L' are conical nozzles arranged in a circle around a central
nozzle L all in connection with the live steam chamber M (or some supplied
with the live steam and others with exhaust steam from auxiliary engines as
previously described) and all discharging into the same receiving cone R sur-
rounded as before with a condensing and feed-water heating coil.
In Figures 9 and 10 L³ are three parallel flat nozzles of which the orifices are
in the form of long narrow slits from which the steam issues in flat sheets and is
delivered into a cone R of corresponding flat shape surrounded as before with a
condensing and feed-water heating coil, and in Figure 11 L is a single such
nozzle and cone.
In either case the nozzles and the entrance to the receiving cone are enclosed
by a chamber in connection with the generator furnace as and for the purpose
before specified.
Steam is supplied preferably by a pair of boilers (or by a single boiler or by
more than two) each of the particular construction hereafter described, whereby
to filter the water and heat it to a sufficient extent to cause the deposit of scale
(at the position where it is least injurious and whence it can be most easily with-
drawn before the entry of the water into the steam generating portion proper.
Each has a forced circulation and comprises a lower series of coils or straight
tubes U of relatively large section enclosing the furnace at the sides and back,
the ends of the straight tubes U being connected with superposed corner chambers
or headers V the said corner chambers or headers, which are situated at the
front of the furnace, being adapted to couple together in pairs the front ends of
adjacent superposed tubes U the uppermost tube of a pair so coupled at the one
side being the lowermost of a pair at the other side, so that the tubes U form a
continuous zigzag coil extending around the three sides of the furnace to and
ro from side to side throughout the whole series of tiers of tubes. All of the
orner chambers or headers have hand-holes and cover plates in alignment with
he various tubes to admit of the tubes being packed with porous material and
eing cleaned out when required. The furnace front is enclosed by horizontally
inged doors and the incandescent fuel is kept out of contact with the tubes Ü
y vertical extensions W of the fire grate exending upwards at all four sides of
he furnace at a short distance within the coil of tubes and the doors, the vertical
rate which is next the door being also hinged for purposes of stoking. Pro-
ision is made for the passage of air from the ash-pit between the vertical
xtensions of the grate and the enclosing structure so that these vertical exten-

page_text: sions increase the effective grate area for purposes. of combustion. The steam.
generating part of the boiler consists of concentric series of cylindrical coils X of
small diameter connected at the lower end with the uppermost tube U¹ and
at the upper end with a superheater Y arranged axially within the coils X so
as to be exposed directly to the heat from the furnace. The tubes U and the super-
posed coils X being enclosed in an external casing of iron plates with a refractory
lining. This superheater Y consists of a vertical drum Y traversed in the vertical
direction by a central tube y screwed at its ends into the top and bottom
castings Y, Ye, of the drum for which it also serves as a central stay rod. It
has perforations y¹ near its lower part opening into the surrounding space within
the drum Y and the steam enters the upper end of this central pipe y from
the pipe (connected with the upper end of the innermost of the generator
coils X) through a reducing nozzle Z of small bore so as to enter the superheater
at a reduced pressure at the same time that its temperature is maintained or.
increased by the action of the superheater. The steam passes down the central
tube through the perforations into contact with the walls of the lowermost
and hottest part of the drum Y wherein it rises and passes off through a pipe to
the chamber M of the jet apparatus. The feed water is supplied by the feed
pump through a pressure equalizing air vessel Q² wherein a pressure is main-
tained superior to that in the generator, the feed water then passing through the
water jacket of the receiving cone R of the jet apparatus wherein it is heated,
then through any suitable known kind of feed water heater, and enters in a
steady stream the lowermost tube of the coil surrounding the furnace wherein
its temperature is still further raised. The concentric coils X instead of being
connected in series as shewn may be separately connected with the lower coil U
so as to be supplied independently with heated water therefrom.
struction of boiler herein described forms the subject of another application of
As the con-
even date herewith, I do not herein claim such construction.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:-
1. The herein described system or combination of apparatus for the pneumatic
propulsion of vessels, comprising a steam generator of the continuous coil type
whereof the lower part surrounds at a distance a
horizontal and vertical fire grates, a superheater above the furnace and within
fire chamber enclosed by
the steam generating coils and in connection therewith by a pressure reducing
appliance; steam jet induction apparatus in connection with the superheater and
a receiving cone, the jet nozzle or nozzles, being enclosed in a chamber in con-
nection with the furnace so as to draw therefrom the products of combustion
whereby an induced draught is produced for maintaining combustion in the
furnace and the steam jet is maintained at the temperature necessary for its
efficiency means of cooling the receiving cone by means of the feed water so
as to partially condense the steam and reduce the volume of the air and gases
passing through the cone and at same time heat the feed water; a valve for
controlling the distribution of the air and gases; trunks for conveying the air and
gases to the emission orifices; condensers placed in said trunks for condensing
steam contained in the air and recovering the same as feed water; a hull having
its bottom upwardly inclined at each extremity, flat in transverse section and
extending the full width of the hull at that part, with downwardly projecting
lateral and intermediate longitudinal flanges or projections forming channels
along the inclined bottom; an upcast and downcast air emission passage com-
municating with the trunks and opening through the inclined bottom by a
narrow orifice extending transversely as nearly as possible the full width of
the hull, the passage being divided to correspond to the air trunks and to the
channels below the inclined bottom so as to enable the emission of the air to be 5
controlled and directed as required for steering, substantially as specified.
5

page_text: 2. In a pneumatic system of propulsion a steam jet' induction apparatus
for supplying the stream of air for propulsion, consisting of steam jet nozzles
and a receiving cone, the combination with the receiving cone of means of cooling
the cone and thereby reducing the volume of the air in passing through the
cone so as to enable the diameter of the throat of the cone to be reduced and the
efficiency of the apparatus to be correspondingly increased as specified.
3. In a pneumatic system of propulsion, a steam jet induction apparatus
supplied with live steam from a generator and a receiving cone provided with
means of cooling the cone the nozzle being enclosed within a chamber in com-
munication with the furnace of the generator so as to draw therefrom the
products of combustion whereby an induced draught is produced for maintaining
combustion in the furnace, the steam jet is maintained at the temperature
necessary for its efficient action, and the current of air required for purposes of
propulsion is supplied substantially as specified.
4. In a pneumatic system of propulsion, a steam jet induction apparatus
comprising a principal nozzle of interrupted annular form in combination with
a receiving cone, said nozzle being supplied with live steam from a generator, a
compound auxiliary nozzle comprising a nozzle connected with the exhaust of
the feed pump or other auxiliary engine, and a second smaller nozzle connected
with the live steam supply for both of which the principal nozzle is adapted to act
as receiving cone, the said principal and auxiliary nozzles being enclosed in a
chamber in communication with the generator furnace so as to produce an induced
draught therein, ensure the maintenance of the temperature of the steam on
issuing from the nozzles, and supply the current of air for purposes of propulsion.
5. In a pneumatic system of propulsion a steam jet induction apparatus
comprising a cluster of steam nozzles in combination with a single receiving cone
and with an enclosing chamber in communication with the generator furnace so
as to produce an induced draught therein, ensure the maintenance of the tem-
perature of the steam jets, and supply air for purposes of propulsion.
6. In a pneumatic system of propulsion a steam jet induction apparatus
comprising one or more flat nozzles from which the steam issues in the form of a
thin flat sheet, in combination with a correspondingly shaped receiving cone, and
with a chamber enclosing the nozzles and the entry to the receiving cone, said
chamber being in communication with the generator furnace so as to produce
an induced draught therein, ensure the maintenance of the temperature of the
steam jets, and supply air for purposes of propulsion.
7. In a pneumatic system of propulsion the construction of the hull with an up-
wardly inclined bottom at each extremity, flat in transverse section and extending
as nearly as possible the full width of the hull at that part and with downwardly
projecting lateral and intermediate flanges forming longitudinal channels below
the inclined surface, a narrow air-emission orifice opening through the inclined
surface and extending transversely the full width thereof, an upcast and down-
cast air passage leading to said orifice and divided transversely to correspond to
the longitudinal channels beneath the inclined bottom of the hull, substantially
as described.
8. In a pneumatic system of propulsion the combination with a hull having an
upwardly inclined transversely flat bottom at each extremity divided into longi-
tudinal channels and having transverse air emission orifices and upcast and
downcast passages leading thereto and divided to correspond to the said channels,
of air trunks or conduits leading to such passages, and a distributing valve or
appliance for controlling the emission of air at the one or the other or at any
part of the one or other emission orifice as may be required for purposes of pro-
pulsion, steering, or manoeuvring, as described.
9. The pneumatic propulsion of vessels by the reaction of a steam impelled stream
of air from which the heat has been abstracted, and the steam has been separated
by condensation before the cooled air is used for purposes of propulsion, the

page_text: method being carried into effect by means of induction and condensing apparatus
substantially as specified.
Dated this 27th day of January 1899.
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.

page_text: Complete
PROVISIONAL SPECIFIC
Improvements in Steam Generators.
I, WALTER CARR, of 5, Earlham Road, Bowes Park, Wood Green, London, N.,
ngineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to improvements in steam generators, particularly
enerators employed for marine purposes, and has for its object to provide a
generator adapted to heat and filter the feed water and to favour the deposit of
scale at the position where it is least liable to injuriously affect the generator
and from which it can be easily withdrawn.
The invention consists essentially of a generator composed of a series of coils
or tubes enclosing the furnace at the sides and back, the lower coil which forms
the base and which supports and encloses the furnace grate consisting preferably
of straight tubes of relatively large diameter packed with suitable porous material.
The ends of the tubes forming the coil connect with corner chambers or headers
whereby the front, ends of adjacent side tubes are connected together alternately
at the one and the other side so as to form a continuous zigzag coil extending
The corner chambers or
around the three sides of the furnace in the lower tier, then connecting with the
second tier which extends back around the three sides of the furnace to the opposite
side where it connects to the third tier, and so on.
headers have hand holes in alignment with the various tubes of the coil which
connect with such headers to admit of such tubes being easily cleaned out. The
20 upper or succeeding coils may be of smaller diameter and are intended to act more
especially as evaporators and superheaters for the steam which they deliver into
a cylindrical chamber or steam drum. The feed water is supplied in a steady
stream, through an accumulator or pressure equalizer, to the lowermost series of
coils, or to each coil independently, the circulation being thus of the controlled
25 type.
The whole.of the coils constituting the generator or only a portion thereof, may
he enclosed in a sheet iron casing which may or may not be lined with some suit
material.

page_text: same is to be performed to be particularly described and ascertained in and by
the following statement:-
My invention relates to improvements in steam generators particularly
generators employed for marine purposes, and has for its object to provide a
generator adapted to heat and filter the feed water and to favour the deposit of
scale (at the position where it is least liable to injuriously affect the generator and
from which it can be easily withdrawn) before the entry of the water into the
steam generating portion proper.
The invention consists essentially of a generator composed of a series of coils
of tubes the lower coil which forms the base and which supports
and encloses the furnace grate at the sides and back consisting preferably
of straight tubes of relatively large diameter packed with suitable porous material,
and connected with corner chambers or headers in such manner that the front ends
of adjacent side tubes are connected together alternately at the one and the other
side so as to form a continuous zigzag coil extending around the three sides of the
furnace, that is to say the lower tier of tubes connects with the second tier at one
side which in turn connects to the third tier at the opposite side, and so on. This
lower coil is surmounted by and connects with a series of concentric cylindrical
coils formed of tube of smaller diameter and intended to act more especially as
evaporators, the last coil of the series leading to a cylindrical chamber or steam
drum forming the superheater proper. The feed water is supplied in a steady
stream, through an accumulator or pressure equalizer, to the lowermost coil, the
circulation being thus of the controlled type.
Instead of the upper coils of small diameter being in series to each other they
may all be connected directly with the lower coil so that each will be supplied
with water therefrom independently of the others.
Reference is to be had to the accompanying drawings forming part of this specifi-
cation wherein Figure 1 is an elevation of a pair of generators (one of them being
represented in section) as arranged for use on a shallow draught vessel. Figure 2
is a vertical section of the superheater shewing the device for reducing the pres-
sure of the steam as it passes from the generator to the superheater.
The generator is constructed of a lower coil or series of straight tubes A of
relatively large section, enclosing the furnace at the sides and back, the ends of
the straight tubes A being connected with superposed corner chambers or
headers B B. The headers B₁ situated towards the back of the furnace are mere
right angled connections for single tubes of the same tier but the headers B to-
wards the front of the furnace are adapted to couple together in pairs the front
ends of adjacent superposed tubes A the uppermost tube of a pair so coupled at the
one side, being the lowermost of a pair at the other side, so that the tubes A form
a continuous zigzag coil extending around the three sides of the furnace to and fro
from side to side throughout the whole series of tiers of tubes; all of the corner
chambers or headers have hand-holes and cover plates in alignment with the
various tubes to admit of the tubes being packed with porous material and being
cleaned out when required.
The furnace front is enclosed by horizontally-hinged doors and the incandescent
fuel is kept out of contact with the tubes A by vertical extensions C of the fire-
grate extending upwards at all four sides of the furnace at a short distance within
the coil of tubes and the doors, the vertical grate which is next the doors being also
hinged for purposes of stoking. Provision is made for the passage of air from the
ash-pit between the vertical extensions of the grate and the enclosing structure so
that these vertical extensions increase the effective grate area for purposes of com-
bustion.
The steam generating part of the boiler consists of concentric series of cylindrical
coils D of small diameter connected at the lower end with the uppermost tube A
and at the upper end with a superheater E arranged axially within the coils D
so as to be exposed directly to the heat from the furnace. The tubes A and the
superposed coils D being enclosed in an external casing of iron plates with a

page_text: efractory lining. This superheater consists of a vertical drum E traversed in
screwed at its ends into the top and
he vertical direction by a central tube e
bottom castings E, E, of the drum for which it also serves as a central stay rod.
It has perforations near its lower part opening into the surrounding space within
the drum E and the steam enters the upper end of this central pipe e from the
pipe (connected with the upper end of the innermost of the generator coils D)
through a reducing nozzle F of small bore so as to enter the superheater at a
reduced pressure at the same time that its temperature is maintained or increased
by the action of the superheater. The stean passes down the central tube e
through the perforations e¹ into contact with the walls of the lowermost and hottest
part of the drum E wherein it rises and passes off through the steam delivery
pipe G. The feed water is supplied by the feed pump H₁ through a pressure
equalizing air vessel H2 wherein a pressure in maintained superior to that in the
generator, the feed water then passing through any suitable known kind of feed water
heater and entering in a steady stream the lowermost tube a of the coil surround-
ing the furnace wherein its temperature is still further raised. The concentric
coils 1 instead of being connected in series as shewn may be separately connected
with the lower coil A so as to be supplied independently with heated water there-
from.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I claim
is:-
1. A steam generator of the continuous coil type constructed of a combination of
coils of large and small diameter comprising a lower coil composed of straight
tubes of relatively large diameter (whether packed or not with porous material)
connected in zigzag order by headers and enclosing at a distance the three sides a
fire chamber constructed of horizontal and vertical grates, the zigzag coil being
adapted for heating the water and precipitating scale and being connected to and
surmounted by concentric circular evaporating coils of tube of relatively small
diameter connected at the upper and through a reducing nozzle with a superheating
drum placed over the furnace and within the evaporator coils substantially as
described.
2. In a steam generator of the herein described type, the employment of a grate
having upwardly projecting side grates so as to keep the incandescent fuel from
contact with the enclosing coil, and allow access of air to the fuel substantially as
specified.
1000
Dated this 2 day i van
A. M. & WM. CLARK,
Chartered Patent Agents,
53, Chancery Lane, London.