Year: 1888

page_text: I, HENRY FORDHAM of 43 Argyle Square, Kings Cross, in the County of Middlesex,
Organ Builder, 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 :-
My invention relates more particularly to the swell box and its connected parts and
consists of means whereby the swell action is rendered more efficient than
heretofore.
For this purpose I employ in connection with the swell box a simple arrangement
of mechanism whereby I am enabled to open and close the venetians or shutters
in any desired order within certain limits and retain them in any desired position
thus ensuring the better performance of the crescendo and decrescendo and other
effects.
And I also employ means to ensure the more gradual opening and closing of
the air or sound ways between the venetians or shutters, means to effectually close
the joints between the closed venetians or shutters and the case or frame of the
instrument and means to permit the free exit of waste air from the swell box when
the venetians or shutters are closed and yet prevent the escape of any volume
of sound therewith.
And in order that my said invention may be more clearly understood and readily
carried into effect I will proceed aided by the accompanying drawings more
fully to describe the same.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a front elevation of part of an organ showing my invention applied
thereto and Figure 2 is a side elevation thereof partly in section. Figure 3 is
a front elevation partly in section of the gradation rod and principal operating parts
separately. Figure 3 is a plan of the top of the spindle of the gradation rod
and Figure 4 is a sectional plan thereof.
Figure 5 is a detail view showing the means employed for slightly raising and
retaining the gradation rod clear of the shutters or venetians during the changing
operation.
a
Figure 6 is a detail view showing the venetians or shutters opening in varied order.
Figure 7 is an underside view of one of the venetians or shutters showing
device for ensuring the niore gradual opening and closing of the air or sound ways
between the venetians or shutters.

page_text: Figures o and are respectively elevations taken at right angles to each other or
the gradation rod separately.
Figure 10 is a plan of the upper part of the swell box with the top removed,
showing a device for hermetically closing the vertical joints between the venetians or
shutters and the frame and Figure 11 is a front view therefor.
Figure 12 is a side elevation of a device for retaining the swell pedal and
consequently the gradation rod and venetians or shutters and other connected
parts in any desired position and Figure 13 is a front view thereof partly in
section.
Figure 14 is a plan of the joint connecting this device with the case of the
instrument.
Figure 15 is a horizontal section taken on the line A. B. of Figure 12.
Figure 16 is a side view of the pedal separately, Figure 17 is a plan and Figure 18
is a transverse section thereof taken on the line C. D of Figure 17.
Figure 19 represents an elevation partly in section of a modified arrangement
of parts to enable the turning or changing of the gradation rod to be effected without
running it out of its working position and Figure 20 is a plan thereof.
Figure 21 represents a sectional elevation of a modified arrangement of parts for
effecting the same object.
Figure 22 is an elevation of parts showing a method of mounting the lower end of a
gradation rod formed with only a single leaf and Figure 23 is a sectional plan thereof.
Like parts are indicated by similar letters of reference in all the figures of the
drawings and Figures 3 to 21 are drawn to an enlarged scale for the sake of
clearness.
I will first describe the arrangement of apparatus represented at Figures 1 to 18.
a represents the frame of the instrument and b represents the swell box the
front of which is provided with a number of venetians or shutters c as usual.
Instead however of opening and closing the venetians or shutters only in the same
order and to an equal extent in the manner heretofore adopted I according to
my invention act upon such venetians or shutters c in any desired order within certain
limits by means of a gradation rod d.
This gradation rod d is preferably formed with four, but it may be formed with
other suitable number, of leaves d* fixed upon a central spindle d' as shown and each
of such leaves d* is formed with a number of open ended slots or cams therein
of different form to receive anti-friction rollers carried by arms or cranks c¹ fixed
to the fronts of the shutters c so that by raising or lowering the gradation rod d each
shutter or venetian c will be opened or closed in manner according to the shape of its
respective slot or cam d².
The slots or cams d² of the gradation rod d may be so shaped or timed to act upon
the series of venetians or shutters e composing the swell front that very varied effects
may be produced.
For example the slots or cams may be shaped in such manner that they will
act upon the shutters c in regular order one slightly in advance of the next following
one either from top to bottom of the entire series or from bottom to top thereof
or such movement may commence at the centre of the series of shutters or venetians c
and gradually extend from one to the other both upwards and downwards or it may
commence at the top and bottom and be continued towards the centre or the venetians
or shutters c may be opened in irregular order or many other varied and novel effects
may be produced by shaping the slots or cams d² to act upon the shutters c in
the manner desired or the slots or cams d² may be shaped to open and close the
shutters c altogether as heretofore.
It will be evident that the gradation rod d may be formed with one, two, three,
four or other suitable number of leaves, according to the number of changes
desired.
The venetians or shutters c or the cranks c¹ may if desired be weighted in order to
assist their return to their normal or closed position.
The lower end of the spindle d' of the gradation rod d normally rests upon or

page_text: is suspended slightly above a projection h¹ from a rod h which is capable of rising and
falling in guides fixed to the frame a and is furnished at its lower end with a
weight h. To the rod is connected one end of a chain or cord h the other end of
which is passed partly around and connected to a disc or wheel h³ keyed upon
a shaft he provided with a crank pin A'.
Upon this crank pin h' is mounted one end of a connecting rod the other end of
which is pin jointed to an arm or lever which is keyed upon a
rocking shaft
carried by brackets fixed to the frame a; an arm or lever mounted at right
angles to the arm or lever is also keyed upon the shaft and the outer end thereof
is pin jointed to one end of a connecting rod i¹ of the swell pedal i.
It will thus be seen that by depressing the swell pedal i rotary motion will be given
to the disc or wheel h and thence through the cord or chain a rising motion will
be imparted to the rod h which in its turn by means of its projection will raise the
gradation rod d thereby opening the venetians or shutters c.
Upon allowing the pedal to rise, it and the disc or wheel h³ and its connected
parts will be returned to their normal position by the weight h³ and the gradation
rod d will fall by its own gravity and thereby close the venetians or shutters c.
The swell pedal i may be retained in any desired position within its traverse
by means of a simple device which I will now proceed to describe.
Beneath the key board and fixed to the frame or case 2 of the instrument is a
bracket from which is suspended by means of a universal joint ja rod j formed
with a toothed rack j³ on one face thereof and provided upon the opposite face with a
spring which takes an abutment against, and is regulated by a disc j* provided
with a threaded spindle 10 screwing into a block or bracket jupon the frame
or case a.
Upon this rack rod j slides a tube or sheath is provided upon one side thereof
with a stud or spindle the end of which is tapped to receive a nut j'. The stud
or spindle passes through a hole i formed in the depending side of the pedal i
and is there secured by the nut and such depending side of the pedal i is formed
with a laterally projecting tooth which takes into the rack of the rack rod j.
The stud or spindle ja has considerable endway movement in the holo so that
although the rack j is normally kept in gear with the tooth upon the pedal i by
means of the spring ja lateral pressure of the foot of the performer against the sheath
or tube will disengage the rack j³ from the tooth of the pedal and permit the
pedal i to freely rise and fall but upon removing the lateral pressure of the foot the
rack will engage with the tooth and hold the pedal i at any desired point of its
traverse. The sliding tube or sheath in addition to serving as a moveable con-
nection between the rack rod and the pedal i also acts as a guard or shield to
prevent the foot of the performer coming into contact with the rack j³.
By means of this device the performer is enabled to lock the swell pedal i and
consequently the gradation rod d and shutters c and other connected parts in any
desired position within the limits of their traverse and remove his foot from the pedal i
and employ it for other purposes.
Each leaf d of the gradation rod d according to the arrangement shown in the
drawings being formed with a series of slots or cams d² differentially shaped or
timed to act upon the venetians or shutters c and thus produce varied effects it becomes
necessary to frequently bring a new leaf d* of the gradation rod d into action and to
effect this change it is necessary to revolve the gradation rod d until the required leaf
thereof is brought into position to act upon the venetians or shutters c. This, it is
impossible to do, according to this arrangement, without removing the rod d out of
connection with the venetians or shutters c and bringing it into gear with suitable
mechanism to impart the required degree of rotation thereto and this movement I
accomplish in the following manner.
In this operation it is first desirable to slightly raise the gradation rod d clear of
the anti-friction rollers c* of the arms or cranks c¹ of the shutters c and for this
purpose I mount one end of the sliding shaft in a bearing g' held with capability of
rising and falling in a seat g³ formed in the bracket g and I give the necessary rising

page_text: motion to the bearing & of the shaft fat the desired times by means of a wedge k
which is forced between the bearing 9 and the bottom of the seat g³ which is bevelled
or curved to facilitate the entrance of the nose of the wedge k.
The rear end of the wedge k is pin jointed to an arm or lever k¹ which is keyed
upon a shaft mounted at one end in a bearing g' formed on the bracket g and at or
near the other end in a bearing ³ fixed to the fratne a. Upon the other end of this
shaft is keyed a lever k' which when desired is depressed and so held by means of a
prolonged shoulder 2 formed upon a draw rod which terminates in a stop 1 at the
keyboard of the instrument.
A projection 7* upon the draw rod returns the wedge k and its connected parts
to their normal position, or I may employ other suitable means for slightly raising the
gradation rod d.
The gradation rod d may now be run out of connection with the venetians or
shutters and moved into gear with the turning mechanism by the following
means.
Upon one side of the draw rod is formed or provided a projection ³ which in the
continued drawing out of such rod acts preferably through a coiled spring, upon a
similar projection m formed on or carried by a draw rod m and thus imparts a
slightly delayed or retarded motion thereto and a second projection m³ upon the rod m
engages with the projection 13 upon the rod to give motion to the rod m in the
opposite direction.
Upon the opposite side of the draw rod m is provided a toothed rack m² which
gears into a toothed segment n keyed upon the lower end of a vertical shaft n
which is provided at each end thereof with adjustable V centres or bearings n*, n*,
upon which it is capable of revolving.
Upon the upper and lower ends of the vertical shaft n are respectively keyed
toothed segments n³, n², which segments respectively engage with a toothed rack e
upon the sliding shaft e and a similar rack upon the sliding shaft by which means
the sliding shafts e and ƒ together may be run out of position carrying the gradation
rod d into gear with the turning or changing mechanism.
In order to prevent the gradation rod a turning in its passage to the changing
mechanism I form cross grooves d in the upper end of the spindle d' thereof which
grooves engage with a straight guide or feather d³ upon the frame a before that arm
of the cross d which happens at the moment to be engaged by the guides g¹ is entirely
withdrawn therefrom and I thus guide the gradation rod & until it gears with the
changing mechanism, or other suitable guiding devices may be employed for this
purpose.
The gradation rod d is now run out of position until the toothed wheel d³ which is
keyed upon the spindle d' thereof engages a toothed segment of keyed upon a short
vertical shaft o mounted in a bearing o carried by a bracket a* upon the frame a.
Formed upon the boss of this toothed segment o' is a smaller segment o² which
engages a toothed rack p³ upon a draw rol p' terminating at the keyboard in a
stop p.
By pulling out the stop p to the required extent which may be clearly ascertained
by marks or indications upon the draw rod p¹ motion may be given to the changing
mechanism until that leaf d of the gradation rod d which it is required to bring into
action is turned into the correct position for engagement with the arms or cranks c¹ of
the venetians or shutters c. The stop may then be pressed in when the gradation
rod d will be run back into position for use with the slots or cams d² thereof engaging
the anti-friction rollers c² of the arms or cranks c¹.
Projections p p upon the draw rod p¹ come against the bracket a* and thus
prevent such draw rod being moved too far in either direction.
In order to prevent the changing mechanism being moved until the gradation rod d
is properly engaged therewith and to let the performer know without doubt which
leaf of the gradation rod d is in action I employ an automatic locking device
which I will now proceed to describe.
Ton the arms of the sevment of I provide a segmental plate of formed with four

page_text: notches or recesses of therein corresponding with the four leaves d* of the gradation
rod d and upon the frame a I mount a spring stop or catch of which normally engages
one or other of the notches or recesses o but is disengaged therefrom and thus
retained by means of a projection upon the sliding shaft coming against such
spring stop o during the changing or turning of the gradation rod d after which the
projection is moved away together with the sliding shaft, and the stop or catch of
then enters that notch or recess of corresponding with the leaf of the gradation rod
now brought into action thus locking the changing mechanism and stop p until a
further change is being made in the gradation rod d.
In order to ensure the more gradual opening and closing of the air or sound ways
between the venetians or shutters c I employ a flap or valve e³ which is hinged at the
top or front edge thereof to the bottom edge of the shutter c and controlled at its
bottom or rear edge by means of a tape c such joint or hinge being covered or
protected by a fillet fixed to the shutter c.
This flap or valve when the venetians or shutters c are closed is covered at its
rear or bottom edge by a bead ce upon the bottom of such venetian or shutter c so
that the shutters or venetians upon their inner face shall present a perfectly even or
unbroken surface and thus avoid any deleterious influence upon the sound of the
instrument.
Each of these flaps or valves c³ is formed of gradually increased width from its
ends cc to the centre c8 as shown at Figure 7 or it might be formed of gradually
increasing width from end to end or from the centre to the ends thereof so that when
the venetians or shutters are opened by the lowering of the swell pedal i the flaps or
valves whose bottom or rear edges then rest upon the upper edges of the venetians
or shutters c (except in the case of the lowermost one of the series which rests upon
the front of the swell box b) shall cause a very gradual opening of the air or
sound ways between the shutters c and render a too sudden opening thereof
impossible.
When the flaps or valves are formed of gradually increasing width from end to
end thereof it is desirable to arrange thein in such manner that the broad and the
narrow ends are not all on one side of the swell front but so that half the broad ends
and half the narrow ends are arranged on each side of the swell front.
The joints between the ends of the venetians or shutters c and the front b¹ of the
swell box in which they are pivotted are not usually made very perfect in order to
ensure freedom from friction and consequently a small space is left between those
parts. This space is very detrimental to the production of perfect swell effects and in
order to obviate this defect I cover these joints when the shutters or venetions are
closed by means of caps or dampers 7 placed one at each sido of the swell box band
the working faces of which are covered with felt or other suitable material.
These dampers or caps q are carried by spring arms q' fixed to the spindles q' which
are mounted with capability of revolving or oscillating in bearings q* fixed to the
sides of the swell box b.
Upon the upper end of each of these spindles q² is respectively fixed a horizontal
crank arm q, q, one projecting towards the front of the instrument and the other
towards the rear thereof and these cranks are at their ends coupled by means of a
connecting rod q pinjointed thereto; a spring 7' which is attached by one end
thereof to the top of the swell hox b and by the other end thereof to the crank arm q',
being employed to normally retain the dampers or caps q in their closed position.
In order to enable the caps or dampers q to be opened or taken off the venetians or
shutters when desired, I connect the horizontal crank arm 9 by means of a link g
with a vertical crank arm g formed with a tail piece q10 and mounted upon a shaft or
axis q carried with capability of rocking or oscillating in bearings q₁ fixed to the
outside of the swell hox b.
The tail piece q 10 is acted upon by a prolonged shoulder formed upon a rising
and falling shaft r in the downward motion thereof which thus moves and holds the
caps or dampers q, off the shutters cat the times desired.
The shaft rises and falls in guides-fixed to the swell box 6 and the lower end.

page_text: thereof is pin jointed to the upper arm of a bell crank lever mounted with capability
of oscillating upon the reduced end of a stud 6 fixed to the frame a and the lower
arm of the bell crank lever ³ is pinjointed to one end of a link the other end of
which is pinjointed to a crank arm h keyed upon the shaft or spindle /* of the band
or chain wheel h³.
By these means the downward motion of the swell pedal i draws down the shaft r
and thus opens or takes the dampers or caps g off the shutters c slightly in advance of
the opening of the shutter c which opening is by the same motion of the swell pedal i
effected through the various connections and the gradation rod d.
When the shutters or venetians e and the caps or dampers 9 are closed the various
joints will be so perfect that the air from the organ pipes s will not be able to find an
exit from the swell box b and in order to obviate this I fit a ventilation opening or
shaft at the upper part of the swell box b and I cover such opening or shaft 63 upon
the inside or it might be the outside of the swell box b with a muffle box * provided
with an aperture open to the waste air from the organ pipes s and fitted with any
suitable number of battles or divisions & forming an extended and circuitous passage
for the waste air in its exit from the swell box b.
By these means a free exit is at all times provided for the waste air but at the same
time the sound is muffled or trapped and prevented passing to the outer air in that
direction.
In the modification represented at Figures 19 and 20 I dispense with the mechanism
for guiding and running out of position the gradation rod d and by the following
arrangement and modification of parts I am enabled to turn or change such gradation
rod in its working position.
For this purpose I remove the material bordering the upper sides of the slots or
cams in the leaves d* of the gradation rod d in the manner indicated by the dotted
lines in Figures 8 and 9 in order that when such gradation rod is turned or changed
no obstruction will be offered thereto by the arms or cranks c¹ of the venetians or
shutters c.
I mount the spindles d' of the gradation rod d with capability of revolving and
rising and falling in bearings e¹, carried by brackets e.f. fixed respectively to the
upper and lower part of the frame a and I fix upon the lower spindle d¹ of the
gradation rod d a long pinion do which engages with the toothed segment o¹ of
the turning or changing mechanism at all times and yet permits the necessary
rising and falling motions to be given to the gradation rod d by means of the
swell pedal and its connected parts in order to open and close the venetians or
shutters c.
In this arrangement as the upper or straight sides of the slots or cams d³ would
not act at the commencement of the lowering of the gradation rod d to close the
venetians or shutters c I preferably weight such venetians or shutters c or the
cranks or arms c¹ as described with respect to the previous figures so that they may
close partly by their own gravity.
The turning or changing mechanism may be locked in order to retain the
gradation rod d with either one of its leaves in position for work by means of
any suitable locking device but I preferably employ for that purpose a spring
catch of mounted upon the frame a* and formed with a rounded nose to take into
one or other of four notches or recesses o' formed in the draw rod p¹ and yet
yield to the movements of the draw rod p¹ and become disengaged from such notch o
when a change is being made in the position of the parts.
At figure 21 I have represented a modification of the arrangement of mechanism
shown at Figures 19 and 20.
In this arrangement, I dispense with the toothed segments o¹o and I cause the
toothed rack p of the draw rod p¹ to gear directly with a toothed wheel de formed
with a boss d' thereon capable of revolving but incapable of vertical movement in the
lower bearing f¹. I form this boss d' and the toothed wheel do with a square hole
therethrough and I form the lower spindle d' of the gradation rod d of a corresponding
shape to fit said hole so that such spindle d' is capable of rising and falling therein and

page_text: of revolving with the toothed wheel de but is incapable of independent or accidental
revolution.
The bearing is formed in two halves, one half taking the form of a cap and being
screwed to the other or fixed half with capability of removal in order to enable the
toothed wheel de together with its boss d to be placed in position.
Although I have not in these modified arrangements shown the lifting mechanism
for slightly raising the gradation rod d previous to turning or changing it I would
have it understood that similar lifting mechanism to that described with respect
to the previous figures may with slight modifications be employed in these examples
also.
When I employ a gradation rod d having only a single leaf d as represented at
Figures 22 and 23 the turning or changing and lifting mechanism is of courso
unnecessary but I mount the spindle d' of the gradation rod d with capability of
rising and falling in guides e, f, carried by brackets e, f, and I preferably form such
spindle of rectangular section and the guides e',' of corresponding shape in order
to prevent rotation of the gradation rod d; or other suitable means may be employed
to effect this object.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed I declare that what I
claim is :-
1. In an organ the employment of a gradation rod d consisting of one or more
leaves d formed with slots or cams 2 therein of various shapes to act upon the
venetians or shutters in any desired order such gradation rod d being acted upon by
suitable mechanism to bring either one of its leaves d* into action when more leaves
than one are employed and receiving a rising motion from the swell pedal i through
suitable connections in manner substantially as herein shown and described and for the
purpose stated.
2. In an organ the employment of a gradation rod d consisting of two or more
leaves d formed with slots or cams d² therein the upper sides of which are cut away
at right angles to the vertical in order to allow of the gradation rod & being turned
or changed in its working position and the lower sides of which slots are formed of
various shapes to act upon the venetians or shutters c in any desired order such
gradation rod d being provided with a long pinion or other suitable device acted
upon by the changing or turning mechanism in order to bring either one of its leaves d*
into action and allow of its rising and falling such gradation rod d receiving a rising
motion from the swell pedal i through suitable connections all in manner substantially
as herein shown and described and for the purpose stated.
3. In an organ the employment of a gradation rod d consisting of two or more
leaves d* formed with slots or cams d therein the upper sides of which are cut away
at right angles to the vertical in order to allow of the gradation rod d being turned
or changed in its working position and the lower sides of which slots are formed of
various shapes to act upon the venetians or shutters c in any desired order the lower
spindle of such gradation rod d being formed square and fitting with capability of
rising and falling in a corresponding square hole formed through a toothed wheel de
and its boss d mounted with capability of revolving in a bearing f³, such toothed
wheel gearing directly with the toothed rack p² upon the draw rod p' in order to turn
or change the gradation rod d and thus bring either one of its leaves d* into action and
at the same time allow of its rising and falling such gradation rod d receiving a
rising motion from the swell pedal i through suitable connections all in manner,
substantially as herein shown and described and for the purpose stated.
4. In an organ the employment of a gradation rod d consisting of one or more
leaves de formed with slots or cams d' therein of various shapes to receive anti-friction
rollers c² carried by arms or cranks c¹ fixed to the venetians or shutters c for the purpose
of opening and closing them in any desired order such gradation rod d being mounted
with capibility of rising and falling in bearings e¹ fl carried by sliding shafts e.
and and provided at its upper end with cross notches or grooves d acting in

page_text: conjunction with a guide or feather d³ and at its lower end with a cross d³ one arm at
a time of which cross takes into guides or provided with other suitable guiding
devices for the purpose of preventing the turning of the gradation rod d in its rising
and falling motions and in its passage to the changing mechanism all in manner
substantially as herein shown and described and for the purpose stated.
5. In an organ the employment of a gradation rod d consisting of one or more
leaves d* formed with slots or cams & therein of various shapes to act upon cranks or
arms 'fixed to the shutters or venetians c for the purpose of opening and closing them
in any desired order such gradation rod d being provided with a toothed wheel do and
mounted with capability of rising and falling in bearings elf carried by sliding
shafts e and f; the sliding shaft being first slightly raised by means of the wedge k
or similar device and both of which shafts e and f are then run out together with the
gradation rod d until the toothed wheel de gears with the changing mechanism in
manner substantially as herein shown and described and for the purpose stated.
6. In an organ the employment in combination with a gradation rod d of means
for slightly raising such gradation rod d previous to running it out of position and
into gear with the changing mechanism such means consisting of a wedge k or other
device receiving motion by suitable connections through a shaft and lever k* from a
draw rod formed with a prolonged shoulder 12 thereon operated from a stop / in
manner substantially as herein shown and described and for the purpose stated.
7. In an organ the employment in combination with a gradation rod d of means
for running such gradation rod out of position and into gear with the changing
mechanism such means consisting of sliding shafts e and provided with racks e
and engaging with toothed segments n², n³, keyed upon shaft n from which another
segment n gears into a rack m³ carried by a draw rod m which receives a slightly
delayed or retarded motion from the draw rod all in manner substantially as herein
shown and described and for the purpose stated.
8. In an organ the employment in combination with a gradation rod d and running
out mechanisin such as that referred to in claim 7, of changing mechanism consisting
of a toothed segment o gearing into the toothed wheel de of the gradation rod d and
which is also keyed a toothed segment o gearing with a
keyed upon a shaft raw rod p' operated by means of a stop p all in manner
rack p carried by a
substantially as herein shown and described and for the purpose stated.
9. In an organ the employment in combination with a gradation rod d and the
running out and changing mechanism referred to in claims 7 and 8 of a locking
device consisting of a segmental plate of formed with notches or recesses of therein
to receive a spring catch o' which is disengaged therefrom during the changing
motion by means of a projection upon the sliding shaft fall in manner substantially
as herein shown and described and for the purpose stated.
10. In an organ the employment in connection with the swell pedal of a rack rod j
suspended by a universal joint j' and formed with a rack and provided with a sliding
tube or sheath connected by a stud or spindle j passing through a hole in the
depending side of the pedal i in such manner that such stud or spindle shall have
considerable end way movement in relation to the pedal, the rack being normally
held in gear with a tooth upon the pedal i by means of a spring * in manner
substantially as herein shown and described and for the purpose stated.
11. In an organ the employment in combination with the gradation rod d, or other
device acting to open and close the venetians or shutters c, of a rack rod j suspended
by a universal joint j¹ and formed with a rack and provided with a sliding tube or
sheath connected by a stud or spindle passing through a hole in the depending
side of the pedal i in such manner that such stud or spindle shall have considerable
endway movement in relation to the pedal, the rack being normally held in gear
with a tooth upon the pedali by means of a spring in manner substantially as
herein shown and described and for the purpose stated.
12. In an organ the employment in combination with venetians or shutters c of
caps or dampers q for closing the joints between the ends of the venetians or shutters c
and the front 61 of the swell box b such caps or dampers 9 being carried by spring

page_text: arms fixed to spindles q² and coupled by means of crank arms 9°, 25, and connecting
rod q and being lifted or taken off the venetiaus or shutters c slightly in advance of
the opening thereof by means of a lever q' connected to crank arins q' by a link q
such lever being provided with a tail piece 410 acted upon by a prolonged shoulder ₁₁
of a rising and falling shaft receiving motion by suitable connections from the swell
pedal i all in manner substantially as herein shown and described and for the purpose
stated.
13. In an organ the employment in combination with venetians or shutters C₁ of
flaps or valves hinged at their front or upper edges to the venetians or shutters c
and controlled at their rear or lower edges by means of tapes or cords et such flaps or
valves being formed at their rear or lower edges of increasing width from the ends
to the centre thereof or vice versa or of increasing width from one end to the other
in order to ensure a very gradual opening and closing of the air or sound ways
between the shutters substantially as herein shown and described.
14. The employment in combination with a gradation rod d of venetians or shutters c
provided with flaps or valves c³ hinged at their front or upper edges to the venetians
or shutters c and controlled at their rear or lower edges by means of tapes or cords c
such flaps or valves c³ being formed at their rear or lower edges of increasing width
from the ends to the centre thereof or vice versa or of increasing width from one end
to the other in order to ensure a very gradual opening or closing of the air or sound
ways between the venetians or shutters substantially as herein shown and described.
15. In an organ the employment of a muffle box 64 constructed and operating in
manner substantially as herein shown and described and for the purpose stated.
16. In an organ the employment in combination, of gradation rod d, venetians or
shutters c provided with flaps or valves c³, dampers or caps q and muffle box 6' all
arranged and operating in manner substantially as herein shown and described and
for the purpose stated.
17. In an organ the employment in combination of a gradation rod formed with
one or more leaves provided with slots or cams therein; means for lifting and turning
or changing said rod in position or means for lifting, running out of position, guiding
and changing or turning said rod; means for holding the swell pedal down and con-
sequently the gradation rod raised in any desired position; venetians or shutters fitted
with cranks or armis to be acted upon by said gradation rod and provided with flaps
or valves for ensuring the gradual opening and closing of the air or sound ways
between such venetians or shutters; caps or dampers for closing at the required times
the joints between the ends of the venetians or shutters and the front of the swell
box; and muffle box or means for causing the waste air from the organ to pass away
through a circuitous passage in order to muffle or trap all sound and yet allow such
air to pass freely away at all times all in mauner substantially as herein shown and
described and for the purpose stated.