IMPROVEMENTS IN THE METHOD OF IMPELLING, CONDUCTING, OR FORCING AIR BY THE INFLUENCE OF A JET OF AIR OR STEAM, AND IN APPLYING THE SAME • TO VARIOUS PURPOSES
Year: 1875

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lanc,
in the County of Middlesex, Patent Agent, for the Invention of
"IMPROVEMENTS IN THE METHOD OF IMPELLING, CONDUCTING, OR FORCING AIR
BY THE INFLUENCE OF A JET OF AIR OR STEAM, AND IN APPLYING THE SAME
• TO VARIOUS PURPOSES."-A communication from abroad by Henri
Félix Louis Worms do Romilly, of Paris, France.
PROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
.Petition, on the 19th May 1875.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lanc, in the County
of Middlesex, Patent Agent,, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE METHOD OF IMPELLING, CONDUCTING,
12 FORCING AIR BY THE INFLUENCE OF A JET OF AIR. OR STEAM, AND IN APPLYING
THE SAME TO VARIOUS PURPOSES," to be as follows:-
'
The following is a résumé. of certain experiments made in investigating
In nhonomone attending the impulsion of air his a int of air an stanma

page_text: This jet projected from a nozzle carries along with it a certain amount
of the ambiant air, which may be made to enter a throat or receiver.
It will be readily understood that the various effects which may be
produced by nozzles of different forms are all comprised as regards the
nature of the phenomena produced in those resulting from the four
following typical forms, viz. :-
The experiments were made thus:-The jet nozzle is placed in com-
munication with a steam boiler serving as a compressed air chamber.
The jet is received in the throat above mentioned which forms the inlet
to a well balanced gas holder. The air passing freely in raises and fills
the holder in a certain time noted by a second's indicator. In this way
the quantity carried along, and the speed at the orifice are measured as
well as the corresponding pressure. When the holder is filled and
stationary it forms a closed recipient, and a gauge attached thereto
indicates the different pressures. The experiment is commenced by
introducing and luting the nozzle in the receiver or throat, and the time
of filling is noted, and the nozzle is then separated from the throat, the
results of the separation and excentration at various distances being also
noted. In this way all the different offects both in a close or open
recipient are obtained according as the gas holder is charged or free.
The following are the results obtained with the various forms of
receivers :-
I. The receiver which gives the maximum result is one of conical
form from 5 to 7 degrees, with the small end towards the jet. The nozzle
should be placed at a distance therefrom, increasing in proportion to tho
area of the receiver, and but slightly with the pressure at the nozzle or
thrower, sco Figure 1 of the accompanying Drawing. In this case the
amount of air received (g) is in the ratio of the diameters of the receiver,
and nozzle g=: D being the diameter of the receiver, and d that of
the nozzlc. The speed V is in the inverse ratio, V = 1; the whole
speed of expansion being supposed to be at the orifice of the nozzle,
q=
D
d

page_text: hence the integral proservation of the quantity of motion. This result is
the same whatever may be the dimensions of the receiver, provided that
the same nozzle be employed in the conditions of maximum indicated.
The following are some results obtained :-

page_text: Maximum maximorum.-Open recipient = 16" 6; closed recipient =
1-52 inch (head of water).
III. For cylindrical receivers with open recipient, the maximum
maximorum is on the axial line at a little distance from the external
orifice. With closed recipient both inside and also at some distance
outside the maxima are on the axis; they then form a closed curve and
the maximum maximorum is a circular line forming the most eccentric
portion of the curve (Figure 3).

page_text: (0.04 in.) to millimetre, the effects of excentration, we shall find very
curious curves containing several maxima and minima. The maximum
maximorum is at the centre and at a distance where the peculiaritics of
the successive curves have gradually disappeared. The quantity of
motion is reduced to less than half of what it is with the conical.
is the least advantageous form of receiver.
This 5

page_text: T, T, T, T, tubes closing all the recipients except only the jet and
receiving orifices.
Thus a successive acceleration with all the effects as regards vis viva
resulting from the the number of jets may be obtained. This mode of
impelling or carrying along the air by successive jets may be sub-
stituted for a single jet in all the applications herein-after explained and
specified.

page_text: nected directly to the wall of the furnace, or form the terminal end of
a tube whose other end is attached to the furnace.
The gases of combustion may either be lost or received in gas holders.
There will be produced according to the amount of air supplied, and in
accordance with methods already known, cither carbonic acid or car-
bonic oxide, which may afterwards be utilized. In the second case the
fire-box will be a gasogene yielding carbonic oxide for all possiblo
purposes, such as the reduction of oxides, combustion, &c. In case of
the subsequent combustion of the carbonic oxide the jet of air or steam
may be again used to impel either the carbonic oxide or the air intended
to effect combustion. By receiving the carbonic oxide produced in a
furnace both the pressure and the inlet and outlet orifices may be cal-
culated, so that the air charged with carbonic oxide may escape with
sufficient velocity to carry with it into a receivor a sufficient amount of
the surrounding air to ensure its own combustion, cither at the time or
in a furnace recipient where its heat of combustion is utilized. The air
finally burnt may in all cases, where its pressure is still to be utilized,
escape with speed from the last furnace and still carry along with it
some of the surrounding air. I shall mention it hereafter in reference
to the air turbine, but it is a feature generally applicable to all the other
examples quoted.
There is a general aversion to injecting a jet of steam in a furnace, as
it is known that steam will extinguish fire, but in the present case
the fire is vigorously supported by the steam jet if it carry along
with it a sufficient amount of air which has been ascertained by many
experiments.
The fuel may be of any description, coke, coal, charcoal, gas, or oil
of any kind, the furnace being arranged accordingly. The jet of
steam may therefore, instead of being projected into the chimney as is
done for locomotive and other steam boilers, bc projected into the
furnace at the front, the door being fitted with the arrangement above
alluded to, and similarly for any chimney, the draught of which is
accelerated by steam blast. The jet should be placed in front of the
furnace, and this jet should carry with it the circumambient air. The
greater the steam pressure the greater will be comparatively the amount
of air carried with it, the pressure to be obtained in the furnace being
the same.
The ict may be utilized for forges and for blast furnaces, as very high

page_text: temperatures may be given to the air carried along as above explained.
The steam far from being injurious in the blast furnace will supply to
the coal free hydrogen eminently fit for the purification of iron.
3rdly. In the same manner a jet of air may be projected into a mass
of molten metal.
4thly. The air impelled or carried along may be likewise utilized for
ventilating large buildings, such as hospitals, or for mines, &c.
In injecting air for mines the steam is supplied by a boiler placed on
the ground, and the air carried along with it is conveyed through tubes,
which may either open into the mine or into the valve chest of an
engine acting like an ordinary steam engine. In this case the air is
utilized as motive power without undergoing any alteration before being
breathed. The jet of air so carried may be used as motive power in
various ways, some of which I will specify.
The jet of steam in all motive apparatus mentioned herein-after may
be replaced by air compressed by the same motor by employing part of
the force produced by combustion to effect such compression in addition
to the other work required. This compression is only produced indo-
pendently of the motor at first starting.
5thly. Air Turbines.-The jet of steam carries along air, which is
directed on the vanes of a turbine. The air imparts motion to the
turbine, which transmits it to the machinery to be operated. The
form and position, whether horizontal or vertical of the turbine may
vary.
The following is a summary description of a turbine, from which
other forms may be deduced:-The steam jet produced by a boiler
carries with it air either into the furnace of the boiler itself or into a
separate fire-box. By combustion the air is heated and expands, and is
allowed to escape only through an orifice calculated so as to have the
continuous delivery of heated air at the pressure given by the surface
of the receiver. It must therefore be allowed to escape through a
larger orifice than that which with cold air would afford a delivery equal
to the admission. The outlet is therefore enlarged proportionately to the
temperaturo imparted to air by combustión, which temperature varies
according to the method of combustion used. It may be desirable to
burn it completely by transforming the oxygen at once into carbonic
acid, or burn it partly by transforming the oxygen into carbonic oxide.

page_text: In the first case the heated air itself serves to carry into a conical
receiver the surrounding air, to which it imparts its heat as well as its
velocity. In the second case where carbonic oxide is produced the jet
charged with carbonic oxide carries air in a second receiver, where its
combustion increases its volume together with its temperature. Hence
this air burnt completely passes in carrying along external air into the
same tube wherein in the preceding caso the air completely burnt at
once passed. Thus whether carbonic acid is at once produced in a
furnace, or whether carbonic oxide is first produced in a first receiving
furnace and afterwards transformed into carbonic acid in a second
receiver, the burnt air will escape, expanded by heat, and carry away
through a conducting tube a certain amount of surrounding air. What
is done here for the air turbine should also be done for any other
mechanical utilization of air; this is a general process. This volume of
air having then a very moderate temperature can be conveyed a con-
siderable distance without being sensibly cooled. The tube, which has
received this air, is bifurcated, forming two similar tubes (A, A, Figure 4),
cach terminating in an annular receiver B fixed at a certain distance
from on either side of and parallel to a turbine C mounted on a hori-
zontal axis D turning between centres E. The axis of the turbine
passes normally through the centre of the opening of the two rings B, B.
These two annular receivers have cach an annular concentric orifice F
provided with guide blades, which project the air against the two rings
of receiving vanes H, H, on either side of the turbine. The area of the
openings of the blades is so calculated as to correspond exactly to the air
admitted in the conducting tube.. The area of the opening of the ring
of vanes should be larger in order that the air jet projected thereon may
carry with it the surrounding air.
Whenever air is projected from a tube in order to carry with it more
air into another tube, or from one annular orifice into another the
edges of the receiver should always be arranged according to the rules
above described. The turbine after receiving the air projected against
cach of its sides allows it to escape tangentially between vanes around
its circumference K. The last-named vanes only may be used, the
guide blades and receiving vanes being dispensed with, retaining only
the annular slits which held them in the same relative position.
The turbine just described is merely an example to facilitato the
comprehension of the more indispensable details..

page_text: To sum up the construction of an air turbine in few words it may
assume any of the forms of the water turbine. The air under pressure
after having passed through one or two receiving furnaces is conveyed
through a tube as water would be in an apparatus provided with guide
blades. The latter project the air against a ring of vanes, whence it
cscapes after having imparted its velocity, thereto. It is unnecessary
that the guide blades should be almost in contact with the vanes as in
water turbines; an interval is left, which enables the air projected to
carry with it the ambiant air against the vanes. The interval between
the vanes and the guide blades, and the dimensions of the rings of guido
blades and vanos, may be varied, but should in all cases be relatively
proportioned in conformity with the principles before laid down, the two
rings being considered as two annular orifices, projector and receiver,
governed by the same laws as the circular orifices referred to at the
commencement of this Specification.
Attempts have already been made to use steam as the motive power
for turbines, but owing to its excessive velocity even at a pressure of
half an atmosphere they have always failed. In the present case this
result is not to be feared as the velocity of a small quantity of high-
pressure steam may be imparted to as large a volume of air as may be
desired without loss.
The speed of rotation of the air turbine which is limited as to size by
the effect of the centrifugal force may therefore be diminished without
detriment, and may be that which is considered most useful, according
to the purpose to which the turbine is to be applied.
6. Hydro-aerial Wheels.-The pressure of air impelled or carried
along may also be utilized (after passing through one or more furnaces)
by injecting it into a certain mass of water. The air tends to rise again
to the surface with a force equal to that which would be produced in
the inverso direction by the fall from the same height of an equal
volume of water. This force is utilized in the same way as that of
water generally by causing the air which tends to rise to pass into
bucket or other such like wheels, or into ordinary turbines; the effect is
the same. It should only be observed that the centrifugal force produces
on the air in water the contrary effect to that which it produces on
water in the air. Thus if the immersed wheel be a bucket wheel and
turn with a certain velocity the air tending by centrifugal force towards

page_text: the axis of rotation lodges against the bottom of the buckets and cannot
escape, which is quite the opposite effect to that which takes place with
bucket wheels in ordinary use where the water tends to flow off at the
periphery. In thus injecting air into water the question arises what is
the velocity with which the air enters the water in order to give the 5
air conducting tube the necessary area for the delivery of the air? This
is what takes placo:-So long as there is water within the tube the air
will not travel beyond the velocity which its pressure imparts to the water,
supposing this pressure to communicate to the water a velocity due to the
height of fall estimated in head or column of water, but as soon as the 1
water is expelled from the tubo and the latter only contains air it cnters
the water with a velocity due to its height of fall estimated in head or
column of air, taking into calculation its compression due to the pressure
which augments its weight, and also the counterpressure of the water from
the submerged orifice of the tubo to the water line. Take as an example 1
a tubo dipping down 30 feet in water. If air be introduced in this tubo
under a pressure of 33 fect of water this air will first enter the tube.
with the speed imparted by water falling a height of 3 feet, but once the
tube emptied the air will flow into the water with the speed of air in air
under a pressure of about one-tenth of an atmosphere, or in other words 2
with a speed corresponding to a fall of about 2600 feet. The section of
the tube way therefore be calculated accordingly.
7thly. Hydro-aerial Navigation. This is another means of utilizing
the air pressure by causing it to enter water as above described and
using afterwards the force developed by the, ascent of the air. Supposing 2
a turbine having but ono vane capable of moving circularly in a hori-
zontal planc as in the case of turbines receiving water from above and
discharging it bencath, if the air contained in the vano were incessantly
renewed at it escapes tangentially the vane will continue to be actuated
by the escape of the air, and its velocity will increase up to a certain 3
point where it is balanced by the resistance. The result will be the
same if the motion of this vane is direct instead of being circular, which
would be the case were not the vane connected to its axis of rotation.
Now this case of the independent vane is precisely the same as that which
occurs in the propulsion of a ship. The apparatus is in that caso very 3
simple. Steam is used (tho impulsion or carrying along and the com-
bustion being effected as at No. 6) to carry along the surrounding air into
a tube opening under water. At the stern of the ship or at its sides there

page_text: "
is cither a large fixed vane or a series of small fixed vanes, the concavity
of the curve being turned in the opposite direction to that in which the
vessel progresses. It is beneath these vanes that the air is forced, it
ascends along the vane and escapes tangentially thereto, and inversely
to the motion of the ship. It must not however be supposed that
because the vessel carrics both the motive air and vane that there is an
cquilibrium. The air once immersed becomes independent, and on
reascending against the vane it will impart thereto the motion due to
its, ascensional force; or in other words it is the water which displaces
the air and moves the vessel. The air being continuously supplied the
speed of the ship will increase until limited by the friction of the water.
Thus a motor is obtained of extreme simplicity and cheapness of con-
struction. This modo of propulsion has been often attempted and
· abandoned, but no experiment had then been made in order to determine
the relative form and position of the two parts, the nozzle or projector
and the receiver, whereby the entire preservation of tho quantity of
movement is ensured.
Sthly. The carrying along of the air operated as above described may
be made to act alternately on the surface of water contained in two
recipients. The water compressed into either of the recipients issues
from it with the velocity due to its compression, and is conveyed'
through a tube into an ordinary water turbine, whence it is discharged,
and returns slowly into the recipient where it is again compressed. The
alternate compression in the two recipients onsures tho constant motion
of the turbine. An air chamber may be interposed between the recipients
and the turbine to regulate the action. When water is to be clevated or
forced in jets as in fire engines, the air pressure on the water in
recipients may be employed directly. The air in that case acts liko
steam in a 'monto-jus." The substitution of air for steam. in the
"monto-jus" is thus effected, whereby a considerable economy is
roalized.
•
If a constant jet of water be required, the air chamber will answer the
purpose. When the recipients are empty the water is re-admitted
through a large valve closing undor internal pressure, and which operates
a smaller one at the entrance of the tube which conducts the water to
the turbine, or to the air chamber, or to the discharge nozzle. A
system of slide valve operated by the turbine in the first case either
closes or opens alternately the air passage to oither recipient, to discharge

page_text: turbine. The water after yielding the most part of its speed to the
turbine re-enters the recipients with a moderate velocity to be again
returned to the turbine. Under this form of using air for compressing
water in a recipient is specified its use for clevating water or any. liquid,
or throwing it upwards. Air will thus replace ordinary elevating
apparatus, plunger pumps, rotary, forcing, exhausting, lift and other
pumps. Air will also advantageously replace in the same manner steam
in the "monte-jus" of sugar refineries, distilleries, and other works.
The air thus impelled may also be utilized for other purposes, those I
have mentioned being but examples, and in nowise cases to which such
use is to be limited. It may be applied in all cases when it is desirable
to utilize air impelled either by air, steam, or more generally a gas by
another gas without loss of the amount of motion through the
application of the principles set forth in this Specification.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Melville Clark in the Great Seal Patent.
Office on the 18th November 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of May, in the year of
our Lord One thousand eight hundred and seventy-five, in the thirty-
cighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Alexander Melville Clark, Her special
licence, that I, the said Alexander Melville Clark, my executors,
administrators, and assigns, or such others as I, the said Alexander
Melville Clark, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Inven-
tion for "IMPROVEMENTS IN THE METHOD OF IMPELLING, CONDUCTING, OR FORCING
AIR BY THE INFLUENCE OF A JET OF AIR OR STEAM, AND IN APPLYING THE SAME TO

page_text: luting the nozzle in the receiver or throat, and the time of filling is
noted, and the nozzle is then separated from the throat, the results of
the separation and excentration at various distances being also noted. In
this way all the different effects both in a close or open recipient arc
obtained according as the gas holder is charged or free.

page_text: similar orifice the pressure is reduced one half.
2. Whenever the orifice of the nozzle may be placed, whether in the
axis or out of it, insido or outside the receiver, the effect is always
superior when the direction of the jet is identical with or parallel to the
axis; any angular direction will produce a very rapid diminution.
3. With the thin sided nozzle the contracted section must be taken a
into consideration as far as regards the speeds or pressures between the
nozzle and the receiver.
.
To establish the facts enunciated the relative forms and sizes of the
nozzle and the receiver have been varied.

page_text: The same experiments have been made with steam, and the very same
results obtained. However, having operated, as in the case of air, with
a pressure of one atmosphere, the drops of water due to condensation
rendered the experiments more difficult and less perfect.
Sucli are the principles in the case of circular orifices, and the same
principles will apply if one of the diameters of the nozzle or of the
receiver, or both, be increased in like manner, each diameter producing
its effect according to the principles above stated. The same results
may be obtained by making the aperture in the nozzle in the form of a
slit, and that of the receiver a larger slit. Similarly the slit may be
made of annular form, facing an annular slit in the receiver, and of
gradually increasing size towards the interior, forming an angle of about
7 degrees, as in the case of the circular receiving orifice (which is
employed, as will hereafter appear, in the case of turbines). Thus it
will be seen that whatever may be the form of the nozzle and receiving
orifices the maximum effect is in all cases due to the reception of the
jet at an orifice forming internally an angle converging towards the
nozzlo.
The fact of the preservation of the amount of movement by means of
the receivers described being well established I will add that the air
may be caused to penetrate by means of a nozzle through a conical
receiver into a first recipient, wherein is located a similar nozzle having
opposite to it a second conical receiver connected to a second recipient
where a third nozzle would meet a third receiver, and so on..
Figure 5 illustrates the principle of a series of successive jets
(combined like the elements of a galvanic battery), the arrangements of
which may however be indefinitely varied..
TTTT. nozzles.

page_text: 6. Different curves for the same receiver when the jet is received in a
closed recipient and in an open recipient.
The principle being once admitted that the velocity of a given volume
cither of air or steam may be transferred without loss of motion to a
greater volume, numerous applications will at once be evident, some of
which I will specify.
1st. Without the use of any blower, fans, or other such like apparatus
I may by a jet of steam or compressed air force any required amount of
air into a furnace by merely using the conical receiver indicated of a
diameter calculatod on the above principles. This receiver may be
connected directly to the wall of the furnace or from the terminal ond
of a tubo whose other end is attached to the furnace.
The gases of combustion may either be lost or received in gas holders.
There will be produced according to the amount of air supplied and in
accordance with methods already known either carbonic acid or carbonic
oxide, which may afterwards be utilized. In the second case the fire-
box will be a gasogene yielding carbonic oxide, which is applicable for
various purposes, such as the reduction of oxides, combustion, &c. In
case of the subsequent combustion of the carbonic oxide the jet of air
or steam may be again used to impel either the carbonic oxide or the
air intended to effect combustion. By receiving the carbonic oxide
produced in a furnace both the pressure and the inlet and outlet orifices
may be calculated, so that the air charged with carbonic oxide may
escape with sufficient velocity to carry with it into a receiver a sufficient
amount of the surrounding air to ensure its own combustion, either at
the time or in a furnace recipient, where its heat of combustion is
utilized. The air finally burnt may in all cases, whero its pressure is
still to be utilized, escape with velocity from the last furnace, and still
carry along with it some of the surrounding air. I shall mention it
hereafter in reference to the air turbine, but it is a feature generally
applicable to all the other examples quoted.
There is a general aversion to injecting a jet of steam in a furnaco,
as it is known that steam will extinguish fire, but in the present case

page_text: mechanical work to perform it is necessary to preserve the greatest
possiblo amount of vis viva. This adaptation may be made by a
calculation rendered simple by the data before given of the boiler
pressure and the diameters of the nozzle and receiver.
5th. If air be substituted for the steam it may, being non-condensable,
be conducted through pipes to any distance, and applied to all the
purposes for which steam is available as motive power. In this manner
motive power may be distributed at great distances from the boiler,
which may bo made of sufficient size to produce steam at a cheap rate.
The power thus obtained may be distributed as and where required,
either for use in the different parts of a large factory or in separate
buildings or works, or at the bottom of a mine, the boiler being in the
latter instanco placed above ground. The air may be inhaled after
being utilized as motive power.
5thly. Air Turbines.-The jet of steam impels the air which is
directed on the vanes of a turbine. The air imparts motion to the
turbine, which transmits it to the machinery to be operated. The form
and position, whether horizontal or vertical, of the turbine may vary.
The following is. a brief description of a turbine from which other
forms may be deduced:-The steam jet produced by a boiler carrics
with it air cither into the furnace of the boiler itself or into a separate
fire chamber. By combustion the air is heated and expands, and is
allowed to escape only through an orifice calculated so as to have a
'continuous delivery of heated air at the pressure given by the surface of
the receiver. It must therefore be allowed to escape through a larger
orifice than that which with cold air would afford a delivery equal to
the admission; the outlet is accordingly enlarged proportionally to the
temperature imparted to air by combustion, which temperature varies
according to the method of combustion used. It may be desirable to
burn it completely by transforming the oxygen at once into carbonic
acid, or burn it partly by transforming the oxygen into carbonic oxide.
In the first case the heated air itself serves to carry into a conical
receiver the surrounding air to which it imparts its heat as well as its
velocity. In the second case where carbonic oxide is produced, the jet
charged with carbonic oxido carries air into a second. receiver where its
combustion increases its volume together with its temperatore. Hence
this air burnt completely, passes in carrying along external air into

page_text: the same tube wherein in the preceding case the air completely burnt
at onco passed. Thus whether carbonic acid is at once produced in a
furnace, or whether carbonic oxide is first produced in a first receiving
furnace and afterwards transformed into carbonic acid in a second
receiver, the burnt air will escape, expanded by heat, and carry away
through a conducting tube a certain amount of surrounding air. What
is donc here for the air turbine should also be done for any other
mechanical utilization of air. This is a general process. This volume
of air, having then a very moderate temperature, can be conveyed a
considerable distance without being scusibly cooled. The tube which
has received this air is bifurcated, forming two similar tubes 'A, A,
Figure 4, cach terminating in an annular receiver B, fixed at a certain
distance from, on either side of, and parallel to a turbine C, mounted on
a horizontal axis D, turning between centros E. The axis of the turbine
passes normally through the centre of the opening of the two rings B, B.
These two annular receivers have cach an annular concentric orifice F,
provided with guide blades which project the air against the two rings
of receiving vanes H, H, on either side of the turbine. The area of the
openings of the blades is so calculated as to correspond exactly to the air
admitted in the conducting tube. The area of the opening of the ring
of vanes should be larger in order that the air jet projected thereon may
carry with it the surrounding air.
Whenever air is projected from a tubo in order to carry with it moro
air into another tube or from one annular orifice into another, the edges
of the receiver should always be arranged according to the rules above
described. The turbine after receiving the air projected against each of
its sides allows it to escape tangentially between vanes around its
circumference K. The last named vanes only may be used, the guido
blades and receiving vanes being dispensed with, retaining only the
annular slits which held them in the same relativo position.
The turbine just described is merely an example to facilitate the
comprehension of the more indispensable details.
"
To sum up the construction of an air turbino in few words, it may
assume any of the forms of the water turbine. The air under pressure
after having passed through one or two receiving furnaces is conveyed
through a tube, as water would be in an apparatus provided with guide
blades. The latter project the air against a ring of vanes whence it

page_text: escapes after having imparted its velocity thereto. It is unnecessary
that the guide blades should be almost in contact with the vancs as in
water turbines; an interval is left which enables the air projected to
carry with it the ambiant air against the vancs. The interval between
the vanes and the guide blades and the dimensions of the rings of guido
blades and vanes may be varied, but should in all cases be relatively
proportioned in conformity with the principles before laid down, the two
rings being considered as two annular orifices, projector and receiver,
governed by the same laws as the circular orifices referred to at the
commencement of this Specification.
Attempts have already been made to use steam as the motive power
for turbines, but owing to its excessive velocity even at a pressure of
half an atmosphere they have always failed. In the present case this
result is not to be feared, as the velocity of a small quantity of high
5 pressure steam may be imparted to as large a volume of air as may be
desired without loss.
The speed of rotation of the air turbine which is limited as to sizo by
the effect of the centrifugal force, may therefore be diminished without
detrinient, and may be that which is considered most useful, according to
the purpose to which the turbine is to be applied.
6. Hydro-arial wheels.-The pressure of air impelled may also bo'
utilized (after passing through one or more furnaces) by injecting it into
a certain mass of water. The air tends to rise again to the surface with
a force equal to that which would be produced in the inverse direction
3 by the fall from the same height of an equal volume of water. This
force is utilized in the same way as that of water generally by causing
the air which tends to rise to pass into bucket or other such like wheels
or into ordinary turbines. The effect is the same, only it should be
observed that the centrifugal force produces on the air in water the
) contrary effect to that which it produces on water in the air. Thus, if
the immersed wheel be a bucket wheel and turn with a certain velocity,
the air tending by centrifugal force towards the axis of rotation lodges
against the bottom of the buckets and cannot escape, which is quite the
opposite effect to that which takes place with bucket wheels in ordinary
use where the water tends to fly off at the periphery. In thus injecting
air into water the question arises what is the velocity with which the air
enters the water, in order to give the air conducting tube the necessary

page_text: arca for the delivery of the air. This is what takes place. So long as
there is water within the tube the air will not travel beyond the velocity
which its pressure imparts to the water, supposing this pressure to
communicate to the water a velocity duc to the height of fall estimated
in head or column of water. But as soon as the water is expelled from
the tube and the latter only contains air, it enters the water with a
velocity due to its height of fall estimated in head or column of air,
.taking into calculation its compression due to the pressure which
augments its weight, and also the counterpressure of the water from the
submerged orifice of the tube to the water line. Take as an example a
tube dipping down 30 feet in water; if air be introduced in this tube
under a pressure of 33 fect of water, this air will first enter the tubo
with the speed imparted by water falling a height of 3 feet, but once the
tube emptied the air will flow into the water with the speed of air in air
under a pressure of about one-tenth of an atmosphere, or in other words
with a speed corresponding to a fall of about 2600 feet. The section of
the tube may therefore be calculated accordingly.
7th. Hydro-ærial navigation.-This is another means of utilizing the
air pressure by causing it to enter water as above described, and using
afterwards the force developed by the ascent of the air. Supposing a
turbine having but one vano capable of moving circularly in a horizontal
plano as in the case of turbines receiving water from above and dis-
charging it beneath. If the air contained in the vane were incessantly
renewed as it escapes tangentially, the vane will continue to be actuated
by the escape of the air, and its velocity will increase up to a certain
point where it is balanced by the resistance. The result will be the
same if the motion of this vano is rectilincar instead of being circular,
which would be the case were not the vanc connected to its axis of
rotation. Now this case of the independent vano is precisely the same.
as that which occurs in the propulsion of a ship; the apparatus is in that
case very simple. Steam is used (the impulsion or carrying along and
the combustion being effected as in section 6, to carry along the
surrounding air into a tube opening under water. At the stern of the
ship or at its sides there is cither a large fixed vane or a series of small
fixed vanes, the concavity of the curve being turned in the opposite
direction to that in which the vessel progresses. It is beneath these vanes
that the air is forced; it ascends along the vane and escapes tangentially
thereto and inversely to the motion of the ship. It must not however

page_text: be supposed that because the vessel carries both the motive,air and vanc
that there is an equilibrium. The air once immersed becomes inde-
pendent, and on reascending against the vane it will impart thereto the
motion due to its ascensional force, or in other words it is the water
which displaces the air and moves the vessel. The air being con-
tinuously supplied the speed of the ship will increase until limited by
the friction of the water. Thus a motor is obtained of extreme
simplicity and cheapness of construction. This mode of propulsion has
been often attempted and abandoned, but no experiment had then been
made in order to determine the relative form and position of the two
parts, the jet nozzle or projector and the receiver, whereby tho ontiro
preservation of the quantity of movement is ensured.
Sthly. The impulsion of the air operated as above described may be
made to act alternately on the surface of water contained in two
recipients. The water compressed into either of the recipients issues
from it with the velocity due to its compression, and is conveyed
through a tube into an ordinary water turbine, whence it is discharged
and returns slowly into the recipient where it is again compressed. The
alternate compression in the two recipients ensures the constant motion
of the turbine. An air chamber may be interposed between the
recipients and the turbine to regulate the action. When the water is to
be clevated or forced in jets as in fire engines the air pressure on the
water in vessels or chambers may be employed directly. The air in that
caso acts like steam in a "monte-jus." The substitution of air for steam
in the "monte-jus" is thus effected whereby a considerable economy is
realized.
If a constant jot of water be required the air chamber will answer the
purpose; when the recipients are empty the water is readmitted
through a large valve closing under internal pressure, and which
operates a smaller one at the entrance of the tube which conducts the
water to tho turbine or to the air chamber or to the discharge nozzlc.
A system of slide valve operated by the turbine in the first case either
closes or opens alternately the air passage to either recipient to dis-
charge the water through a nozzle or to clevate it. The slide valve may
be worked by hand or by a machine; a small turbine might be used for
the
purpose and worked by the water itself..
9thly. Among other uses to which a steam jet may be applied for
impelling purposes may be cited its employment in the manner herein-

page_text: before indicated for exhausting illuminating gas from the retorts, and
conveying it to the gas holders after its manufacture, or similarly for
conducting any other gas from one receptacle to another. The nozzlo
and receiver will thus serve as a substitute for the exhausters now
employed in gas works. The steam in this case in addition to its
mechanical force aids by its condensation in precipitating the tarry
matters and particles passing away with the gas, and thus cffects its
preliminary purification.
To sum up I have in this Specification set forth the use of projecting
and receiving nozzles herein above described, so as to retain the whole
amount of motion ofj a jet of air, steam, or gas, the maximum effect
being indicated as obtained by a nozzle placed at a distance, and by a
conical receiver of about soven degrees with its small and towards tho
jet; I have also shown that the air carried along may vary in amount
without loss in the quantity of motion by varying the receiving orifice,
and its distance from the nozzle; I have given the rules for the quantity,
thic velocity, and pressure of the volume impelled relatively to the
volume of the jet. I have generalized the form of the receivers used
and also pointed out some uses to which the air thus impelled may be
applied.
1st. As an air jet in furnaces either for producing perfect combustion
or for producing carbonic oxide, the furnace in this case forming a
gazogene. The fuel may be either liquid, solid, or gascous, the furnaco
being modified according to the kind of fucl employed.
2nd. As an air jet in blast and other furnaces.
3rd. As an air jot in a bath of cast iron or other metal in fusion.
4th. For the ventilation of buildings, theatres, hospitals, mincs, and
for other like uses. .
In the four other applications described, tho air is employed as motive
power.
"
5th. For distributing power at a distance from the boiler by the
transformation of the steam into incondensable air.
6th. Use of air thus carried along to actuate an air turbine.
7th. Use of the air forced beneath water for working by its.
ascensional force water wheels or turbines.
Sth. The use of this air after being forced under water for propelling
ships by its ascensional force utilized by means of vanes against which

page_text: the air ascends and escapes tangentially and horizontally in the inverso
direction to the motion of the vessel.
9th. Use of the air thus impelled for compressing water alternately
within two recipients, which discharge this water into an ordinary
turbine.
The water after yielding the most part of its speed to the turbine,
re-enters the recipients with a moderate velocity to be again returned to
the turbine. Under this form of using air for compressing water in a
recipient, is specified its use for elevating water or any liquid, or
throwing it upwards. Air will thus replace ordinary clevating appa-
ratus, plunger, pumps, rotary, forcing, exhausting, lift, and other
pumps; air will also advantageously replace in the same manner steam
in the "monte-jus" of sugar refineries, distilleries; and other works.
The air thus impelled may also be utilized for other purposes, those I
have mentioned being but examples, and in nowise cases to which
such use is to be limited. It may be applied in all cases when it is
desirable to utilize air impelled either by air, steam, or more generally a
gas by another gas without loss of the amount of motion through the
application of the principles set forth is this Specification.
Having described, the nature of the Invention and the manner of
performing the same, I declare that what I claim as the Invention to bc
protected by the hercin-before in part recited Letters Patent is, the usc
of gases impelled by a jet of any gas discharged from a nozzle placed at
a distance from opposite to and in front of a conical receiving orifice of
about 6 degrees (with its small end towards the nozzle), in such manner
as to utilize the whole amount of motion existing within the said nozzle,
or a scrics of nozzles and receivers may be applied so as to act in.com-
bination), all substantially as and for the purposes and applications
herein-before specified.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Eighteenth day of November,
in the year of our Lord One thousand cight hundred and seventy.