IMPROVE- MENTS IN HARMONIUMS AND SIMILAR MUSICAL INSTRUMENTS, AND IN THE MECHANISM OR APPARATHIS CONNECTED THERE WITH." PROVISIONAL SPECIFICATION
Year: 1864

page_text: LETTERS PATENT to James Gilmour, of Glasgow, in the County of
Lanark, North Britain, Manufacturer. for the Invention of "IMPROVE-
MENTS IN HARMONIUMS AND SIMILAR MUSICAL INSTRUMENTS, AND IN THE
MECHANISM OR APPARATHIS CONNECTED THERE WITH."
PROVISIONAL SPECIFICATION left by the said James Gilmour at the
Office of the Commissioners of Patents, with his Petition, on the
13th July 1864.
I, JAMES GILMOUR, of Glasgow, in the County of Lanark, North Britain,
Manufacturer, do hereby declare the nature of the said Invention of
"IMPROVEMENTS IN HARMONIUMS AND SIMILAR MUSICAL INSTRUMENTS, AND IN
THE MECHANISM OR APPARATUS CONNECTED THEREWITH," to be as follows, that
is to say:
This Invention relates to certain improvements in harmoniums, and has for
its objects, first, the power of softening or swelling the bass and treble divisions
of the instrument independently of each other; secondly, the production of a
more refined tone than hitherto obtained, which improvement is produced by
causing the sound from the reeds to travel through a greater distance than
formerly before being emitted, so as to bring about as near as possible the
effect of a sound coming from the pipe of an organ; thirdly, the obtaining of
a greater and more effective variety of sound; fourthly, the production of
finer toned instruments at a much lower rate of cost than hitherto.
[Price 6d.]

page_text: The method under which the present Invention is carried into practice
consists, firstly, in arranging the bass portion of the reeds in such manner that
the pallets over them shall open as near to the back portion of the chest as
possible, whilst in contradistinction to this the treble reeds and pallets are
placed equally near to the front part of the chest, or vice versa, instead of
being arranged in one continuous row as at present. This arrangement of the
reeds enables a complete division to be made between the bass and treble
portion, which is effected by running a partition right over the chest. To
take advantage of this arrangement of the reed chest a box is placed over it,
and which may be made in various ways, one modification of which consists
of an oblong frame fitting the outer edges of the reed chest, and may be
made of various depths; into this frame is fixed the partition which separates
the bass from the treble. This frame is covered with a lid, which renders it
virtually a box when fitted on the reed chest, and in this way the sound is
confined. In the lid or cover of this frame there are cut four openings, one
over the pallets of the reeds, and one at the opposite side in both the bass
and treble chambers, and a pallet or cover is made to move in a hinge, or to
slide over each opening, so that when shut the sound is confined, and soft,
sweet, and apparently distant sound is the result when the one furthest from
the reed pallet is opened, for in this case the sound has to travel as it were
through a pipe or duct to the other end, the upper pallet. immediately above
the first pallet being placed so that when it is also opened the full power of
the instrument may be employed, and a second box similar to and placed
above the one now described may also be used, the advantage of this arrange-
ment being that when the pallet of the wooden box is opened at that end
furthest from the reed pallets, and the pallet of the upper box immediately
above the reed pallets is also opened, the sound having to travel to the end of
the under chamber, and passing upwards through the opening into the upper
chamber, and thence to the opening immediately above the reed pallet
becomes so modified by the length of its passage as to cause it to assimilate
more closely to the fine quality of the pipe or organ kind. The various
pallets or covers are opened and closed in various ways, but the method to
which preference is given under the present Invention consists in extending
the pallet arms to a sufficient length over the back of the chest, whilst from
the end of these arms or levers a string or chain passes down, and is fastened
to a small pulley fixed on a larger pulley, and from the larger pulley there
passes a second chain or string connected to the bellows, so that the more
inflated the bellows become the wider the pallets open, whence by varying the
pressure in the bellows the opening of the pallets is regulated, and the power

page_text: of the tone accordingly. In addition to this the pallets are arranged to be
acted upon by stop batons, and thus they may be caused to be self-acting
or not.
SPECIFICATION in pursuance of the conditions of the Letters Patent, led
by the said James Gilmour in the Great Seal Patent Office on the
13th January 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
GILMOUR, of Glasgow, in the County of Lanark, North Britain, Manufacturer,
send greeting.
WHEREAS Her Most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirteenth day of July, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said James Gilmour. Her special license that I, the said James Gilmour,
my executors, administrators, and assigns, or such others as I, the said
James Gilmour, my executors, administrators, or assigns, should at any time
agree with, and no others. from time to time, and at all times thereafter
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
HARMONIUMS AND BIMILAR MUSICAL INSTRUMENTS, AND IN THE MECHANISM OR
APPARATUS CONNECTED THERE WITH," upon the condition (amongst others) that
1, the said James Gilmour, my executors or administrators. by an instru-
ment in writing. under my hand and seal, or under the hand and seal of one
of them, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause the
same to be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said James Gilmour, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed. to be particularly described and ascertained in and by the following
statement, reference being had to the accompanying Drawings, and to the
letters and figures marked thereon, that is to say:-
My said Invention relates to certain improvements in harmoniums, and has
for its objects, firstly, the power of softening or swelling the bass and treble
divisions of the instrument independently of each other; secondly, the pro-

page_text: duction of a more refined tone than hitherto obtained, which improvement is
produced by causing the sound from the reeds to travel through a greater
distance than formerly before being emitted, so as to bring about as near as
possible the effect of a sound coming from the pipe of an organ; thirdly, the
obtaining of a greater and more effective variety of sound; fourthly, the
production of finer toned instruments at a much lower rate of cost than
hitherto.
The method under which the present Invention is carried into practice
consists, firstly, in arranging the bass portion of the reeds in such manner that
the pallets over them shall open as near to the back portion of the chest as
possible, whilst in contradistinction to this the treble reeds and pallets are
placed equally near to the front part of the chest, or vice versa, instead of
being arranged in one continuous row as at present. This arrangement of
the reeds enables a complete division to be made between the bass and treble
portion, which is effected by running a partition right over the reed chest.
To take advantage of this arrangement of the reed chest a box is placed
over it, and which may be made in various ways, one modification of which
consists of an oblong frame fitting the outer edges of the reed chest, and may
be made of various depths; into this frame is fixed the partition which
separates the bass from the treble. This frame is covered with a lid, which
renders it virtually a box when fitted on the reed chest, and in this way the
sound is confined. In the lid or cover of this frame there are cut four
openings, one over the pallet of the reeds, and one at the opposite side in both
the bass and treble chambers, and a pallet or cover is made to move on a
hinge, or to slide over each opening, so that when shut the sound is confined,
and a soft, sweet, and apparently distant sound is the result when the one
furthest from the reed pallet is opened, for in this case the sound has to travel
as it were through a pipe or duct to the other end, other pallet imme-
diately above the reeds being placed so that when it is also opened the full
power of the instrument may be employed. A second box similar to and
placed above the one now described may also be used, the advantage of
this arrangement being that when the pallet of the under box is opened at
that end furthest from the reed pallets, and the pallet of the upper box imme-
diately above the reed pallets is also opened, the sound having to travel to
the end of the under chamber, and passing upwards through the opening into
the upper chamber, and thence to the opening immediately above the reed
pallet (the pallet of the under swell box being now shut) becomes so modified
by the length of its passage as to cause it to assimulate more closely to the
fine quality of the pipe or organ kind. The various pallets or covers are

page_text: opened and closed in various ways, but the method to which preference is
given under the present Invention consists in extending the pallet arms to a
sufficient length over the back of the chest and swell box, whilst from the end
of these arms or levers a string or chain passes down, and may be fastened to
a small pulley fixed on a larger pulley, and from the larger pulley there passes
a second chain or string connected to the bellows or reservoir, so that the
more inflated the bellows or reservoir become the wider the pallets open,
whence by varying the pressure in the bellows or reservoir the opening of the
pallets is regulated, and the power of the tone regulated accordingly. In
addition to this the pallets are arranged to be acted upon by stop batons, and
thus they may be caused to be self-acting or not,
Another modification of my said Invention, and which is adapted to reed
chests constructed in the usual way, that is to say, with the reeds arranged in
a straight line in both the bass and treble portions, and is consequently
applicable to ordinary harmoniums already in use, and has nearly the same
effect as that herein-before described. In this modification a swell box is
placed over the reed chest, with a division running across the reed chest at
whatever point it may be determined to divide the bass portion from the
treble instead of running lengthwise, as in the one previously described. By
placing in this box another division running the whole length of the chest, and
extending from the back to within a short distance of the front, so as to leave
an opening for the same to pass through, and placing the opening in the
upper portion near the back, it will thus be seen that the sound has to travel
from the reed to the front, and thence back again to the opening in the upper
portion or lid over which the pallets are placed to regulate the emission of
sound.
Another modification adapted to the cheaper class of instruments is to place
the swell box previously described over the ordinary reed chest, but constructed
without any division, the advantage of which for cheap instruments is, that it
is simple and effective, costs a mere trifle, subdues the tone at will, and
improves it, thus producing an instrument much superior than the ordinary
one for private use.
And in order that my said Invention may be properly understood, I shall
now proceed to describe the system, mode, or manner in which the same is or
may be used or practically carried into effect, reference being had to the
several Figures upon the two explanatory Sheets of Drawings which I have
hereunto appended, that is to say:-
On Sheet 1. Figure represents a transverse sectional view of one of my
improved harmoniums, taken through the treble portion of the instrument;

page_text: Figure 2 is a corresponding sectional view of a larger and slightly modified
construction of instrument: Figures 3, 4, and 5 are details, and will herein-
after be more fully referred to.
In Figure the case of the instrument marked A is made. as is usual in
ordinary musical instruments of a similar class, of either rosewood, mahogany,
or other ornamental timber, and within this case is contained the framework
carrying the body or main portions of the instrument; the part marked B is
the key frame, containing the keys C and C, in the under part of which the
pegs or pins D are fitted, and these, when pressure is communicated to the
keys, act upon the stickers D', which in turn pressing upon the pallet levers E
cause the pallets situated over the reeds to be lifted, when the sound from the
reeds immediately follows. The upper part of the instrument. carrying the
rows of keys C and C. together with the stop "batons" F, is attached to the
lower or under part, consisting of the swell box and reed chest, by the hinge
joints G, this frame being secured at the outer end by clamp hooks, hooks
and eyes, as usual. Those portions of the instrument just described and
referred to are in no respect novel or original, and consequently form no part
of my present Invention, my reason for inserting them being to further the
complete elucidation of my actual Invention, to which I shall now more
particularly refer.
Situated immediately below the key frame is the swell box II, made by
preference of the same length and breadth as the reed chest I, over or upon
which it is situated. The upper portion of the swell box H is perforated with
a row of holes, through which the note stickers D' pass in their communica-
tion with the pallet levers E. and extending throughout the whole length of
the swell box II is the slightly inclined division J, shown in transverse section:
upon more particularly referring to the Figure it will be seen that this division
does not extend the entire way across the chest in a transverse direction, but
at the front part of the swell box H an opening is left running throughout its
entire length internal length; this longitudinal opening marked II', together
with that portion of the swell box beneath the division J. is divided at the
centre of its length by a piece of wood running entirely across from back to
front at the part where it may be determined to separate the bass from the
treble, this division of the swell box II thus effectually separating the bass
from the treble portions of the instrument, that portion of the swell box H
situated above the division J is also divided by a central bar situated imme-
diately above the lower one K, thus cutting off a communication between the
treble and bass portions, as distinctly shown in the transverse section, Figure 1,
on Sheet 1. In the upper part or cover of the swell box H two openings K'

page_text: are formed, one over the treble and the other over the bass end of the instru-
ment, and to the interior of the swell box on the under side of the top the
lever L carrying the pallets L', which close over the openings, are fastened by
a moveable joint : these levers pass through holes formed in the back part
of the box II and extend to some distance beyond it. their ends being mounted
with hooks, attached to which are the strings or cords M connecting them to
the piano swell lever N. which particular arrangement will be herein-after
more fully described and referred to. The swell box is connected to the
reed chest in Figure at its back end by the hinges O, as shown, the front
end being secured by clamp hooks in the ordinary manner. which when hooked
into corresponding eyes press the material forming the joint between the swell
box and reed chest sufficiently close together to make it perfectly air-tight.
The stop baton F is connected at its inner end by a pin joint to the bent
lever P: the lower part of this lever passes through a slot hole formed in the
pallet lever L, that portion passing into the slot being formed with a shoulder
above, so that when the stop baton F is pulled out by the player the bent
lever P being brought into a nearly vertical position the distance between its
upper end and the pallet lever becomes greater, owing to the increased virtual
length of the bent lever, thus causing the pallet levers L to be lowered, and
with them their connected pallets 1', thus opening the holes in the upper part
of the swell box. It is evident that by the intervention of this last-mentioned
system of levers the pallets L' may be kept permanently open or closed;
when closed, the pallets L are kept over the openings by springs pressing them
upwards. As it is necessary when using such an instrument as the one being
now specified to produce at times sudden and gradual variations of tone, which
cannot be so effectually carried out with the hand system of stop batons just
referred to, the inner end of the pallet levers L is attached, as herein-before
described, to the piano swell lever or connecting bar N by the cord M': this
lever or connecting bar N has formed on its under side the wedge-shaped pro-
jection N', and is fixed by a hinge to the wind chest, as shown in Figure 1,
the board forming the upper part of the reservoir being extended to some
distance in a backward direction, and upon this projecting part the wedge-
shaped blocks of wood Q slide, they being fixed to one end of a rod Q¹ passing
through the wind chest to the handle R, which when pulled brings forward
the wedge-shaped pieces Q, and owing to these pieces being moved inwards
or towards the narrowest part of the wedge-formed projection N' the contact
between the two parts Q and N is broken. To the lever N there is fixed an
clastic cord or spiral spring S, and this is connected to the bellows or reservoir
of the instruinent; the use of a spring or elastic cord is, that when the piano

page_text: swell is shut or the lever N or connecting bar is prevented from acting, the
elastic cord may give way and allow the reservoir io fill; nevertheless, owing
to its elasticity the spring or cord S is always sufficiently distended whether
the bellows are inflated or not, and it is evident that when the pieces Q are
moved inwards and out of contact with the short lever N, the latter are capable
of being moved downward when force is applied to them; this moving force
exists in the pressure of wind contained in the bellows or reservoir, and it is
further obvious that if the lever N is depressed, owing to its being attached
by a comparatively inelastic cord M to the pallet levers L, the latter must also
be moved downwards to a corresponding extent, which movement consequently
causes the holes in the upper part of the swell box H to be opened by the
pallets L being drawn to a distance from their inner edges. In this arrange-
ment there exists the capability of varying the amount of opening of the
pallets by the pressure of wind in and the degree of inflation to which the
bellows or reservoir are subjected, so that when the musical tones are emitted
through the openings herein-before referred to, the power of the tone may
either suddenly or most gradually be increased or depressed to the utmost
nicety and degree of refinement.
Having now described in detail the various arrangements and systems
of mechanism of that modification of my Invention shown in Figure 1, Sheet 1,
of the annexed Drawings, I shall proceed to point out in what my improve-
ments essentially consist, that is to say, the chief modification of my said Inven-
tion consists in applying over the reed chest. I the swell box H. divided and
constructed in the manner herein-before described, the result of which is the
production of a tone which assimulates very closely to the melodious strains of
the organ, in fact, making the harmonium a much more efficient substitute for
the organ than what has hitherto been accomplished; owing to the special
arrangements of the swell box H, the sound emitted from the reeds when any
of the reed pallets are lifted passes first up through the front longitudinal
opening of that division of the instrument from which it proceeds, arriving on
the top of the inclined sound board it escapes through the pallets L of that
division of the instrument. Supposing the sound to proceed from the treble
portion of the instrument, and that the pallet L over that portion is open, the
sound will be heard modified in tone, owing to its being emitted after having
passed through the swell box, but on the other hand, and if at the time but a
low pressure of wind be employed, the softest and almost inaudible musical
sounds can be produced; these are capable of being very gradually increased
by increasing the pressure in the reservoir by the action of the feet upon the
blowing levers; when the latter is filled to the highest extent possible, by

page_text: suddenly closing the distant pallet and opening the nearest one, the power of
the musical tones are swelled to the utmost extent. It is at once obvious that
the player can produce at will either the highest power of which the instru-
ment is capable, both in the treble and bass portions simultaneously, or it is
equally easy to produce a powerful treble with a very soft and apparently
distant bass, and inversely a powerful bass with a soft and apparently distant
treble.
A second modification of my said Invention is that shown in Figure 2,
Sheet 1; as in the former modification the case A is formed of some orna-
mental or fancy wood; B is the key frame containing the keys marked C and
C', in the under part of which are screwed or otherwise fixed the pegs .D;
motion being imparted to the keys by the pressure of the fingers is communi-
cated by these pegs D to the stickers D', and thence to the reed pallet
levers E. The upper part of this instrument carrying the keyboard and
"stop batons F is attached to the body of the instrument by means of the
hinges G, the frame itself being secured at the front end by means of clamp
hooks, not shown. Placed immediately below the key frame and upper parts
of the instrument is the swell box H of the same size as and fitting close
upon the upper part of the reed chest 1. In the construction of the swell
box H mainly consists the chief features of improvement in this modification
of my said Invention, and as most of the details in this arrangement are
similar to the one herein-before described and referred to, and in some
respects similar to instruments of this class as generally constructed, I shall
now proceed more particularly to specify the peculiar features of the swell
box II, leaving the details of the knee swell and piano swell to be herein-after
referred to.
On referring to Figure 2. Sheet 1, it will be seen that in the upper part of
the swell box two longitudinal openings and I are formed, over these are
situated the moveable pallets I and J, connected by the pallet lever L to
the knee and piano swells mechanism by means of the cords M and N.
Throughout the entire length of this swell box II there runs the horizontal
sound board K, having two openings O and O¹ formed, one being in each of
its alternate ends and at alternate sides, alternating likewise with the
openings I and II in the cover or top portion. Between the cover of this
swell box and its sound board K there is fixed the vertical divisional
strip P; this runs in a diagonal direction throughout the entire length of the
interior portion of the swell box, causing the passages Q and R to he narrower
at one end and wider at the other. There is also a cross division in this swell
box dividing the bass and treble. When the sound is emitted from the reeds

page_text: in the bass division of the instrument, it can be rendered as soft and pleasing
as possible, and in effect is made to appear at a great distance, the reason of
this is owing to its having first to travel through the opening O. its passage is
continued along the upper part of the swell box in that part of it separated by
the partition P before arriving at the further end of the passage Q, which part
being of much larger internal dimensions than the end from which it proceeded,
the intensity of the sound is decreased in an inverse proportion to the distance
through which it has travelled, and the difference between the space at first
and finally occupied. In this modification the same remarks apply to the
treble division of the instrument, and therefore need not be repeated. The
method of acting upon the pallets in the upper part of the swell box by the
pressure of wind in the bellows is similar in this to that described in the
former modification, but in this modification they are also acted upon by the
knec swell, that portion of which connected to the piano swell knob S is
similar in this to that described in reference to the former arrangement, so
that when the two wedge-shaped pieces T and U are pulled at a distance
from one another, the pallets may be opened by means of the tension imparted
to the elastic string connecting the lever V to the bellows or reservoir, or by
means of the knee swell itself, which consists of the cranks W moveable on
joints W, to which the pallet levers L are connected by means of the cord M.
From the lower arm of the crank W there extends a wire or rod parallel to
and on the same horizontal plane as the rod Y. and which consequently
cannot be seen in Figure 2; this rod is again connected to the hinged knee
board Z, which projects out when in use from the front of the case of the
instrument in such manner that the knee being applied to or pressed against
it, a movement is communicated to the crank W and thence to the pallet levers,
which in turn open the pallets to an extent corresponding to the amount of
motion first imparted to the knee board Z, the quantity of motion of the pallets
being regulated by the length of each arm of the crank W and length of the
levers 1. By these two arrangements of mechanism for regulating the
swelling or decreasing of the power of the instrument it is obvious that either
the increase or diminution of tone can be regulated at will either by the knee
swell or by the pressure of sound in the bellows or reservoir acting on the
piano swell.
A third modification of my said Invention is shown in transverse section at
Figure 1, on Sheet 2; this arrangement is intended to be more particularly
applicable to instruments of a larger variety than those herein-before described
and referred to. The case of the instrument in this, as in the former modi-
fications, is made of ornamental timber, but in contradistinction to them it is

page_text: made of a different form, having a large portion projecting upwards from the
body of the instrument; this portion is for the purpose of containing a pair
of ducts for modulating the powers of the instrument, and will herein-after
be more fully described. B is the key frame containing the rows of keys C
and C. The keys C and C are fitted with two sets of pegs I and I'; those
marked I towards the front act upon the front set of pallet levers J by the
intervention of the sticker J', whilst the set marked I' act upon the backward
pallet levers H, also by the intervention of the stickers K. Above the reed
chest there is placed the swell box I of the same length and breadth as the
former, and fitting closely over it. Extending entirely throughout the central
horizontal plane of the swell box L is the sound board M. in which are
formed four openings N, through which the sound as it is emitted from the
reeds passes.
In the cover or lid of the swell box L there are formed four
openings O and O', two of which are only seen in the accompanying section,
but more openings may be used so as to obtain the full power when required.
The front set of openings marked O are closed on the interior by the pallets P,
which are acted upon by the stop batons Q. acting by means of the pro-
jections Q when moved upon the bent lever P, the further end of which
being depressed as the stop baton is drawn out causes the pin P¹ to move
downwards, a corresponding movement being imparted to the pallet lever.
Extending from the openings O' are the conical ducts R, fitted with the
moveable lids or covers R', these being connected to the latter by a suitable
moveable joint S. At the further end of two of the stop batons Q are formed
the vertical projections S¹, and when the batons are pulled forward these
coming into contact with the moveable lever T, cause it to be elevated, and
this in turn imparts an upward movement to the sliding rod U, carried in
the guides U this rod acting against the slides or pallets causes them to be
also lifted. When it is desired to produce musical tones of a medium power
the pallets P2 are opened, and the sound emitted from the two sets of reeds
passes through the openings covered by the pallets P. that emitted from the
reeds G passing in a direction indicated by the arrows marked 1, whilst the
sound emitted from the back set of reeds travels in the direction of the arrows
marked 2. If it is desired to produce a very soft tone, this is effected by
means of closing the pallets P, when the sound, instead of passing through
them, is caused to travel first through the openings in the swell board,
passing thence to the larger ducts R. and finally escapes at the top through
the lid R', which can be opened to any desired extent by means of the stop
batons or by means of the cord V extending to the knee or piano swell and
wind reservoir, as described in reference to the swell box levers of the last

page_text: modification; when the sound passes as in the last-mentioned manner, its course
is indicated by the sets of arrows marked 3. It is obvious that the last
arrangement of swell box and ducts is susceptible of numerous modifications,
and in addition to placing pallets on the top of the chests, they may likewise
be placed in the sides and lower portions, thus enabling a sound to be pro-
duced not of quite so soft a degree as when issuing from the top.
It is obvious that any of the pallets in the herein-before referred to modifi-
cations of my Invention may be made moveable in many other ways besides
those which I have described and shown in the accompanying Sheet of
Drawings; for instance, they may be constructed to move on a central or end
pivot, or to slide around off the openings.
There are also many other methods under which my said Invention may
be put into practice. and a very simple method of modifying the tone of
harmoniums is that shown in plan in Figure 3, and in tramsverse section in
Figure 4, Sheet 1. There two Figures represent a very simple kind of swell
box, which consists of a rectangular frame A. covered by a lid B; this box
fits over an ordinary reed chest, and may be aflixed thereto in any convenient
manner: The stickers for actuating the reed pallet levers pass down through
the holes C, which are continued along the swell box in the direction of the
dotted line. In the cover of this swell box two openings are formed covered
by the moveable pallet D; they are connected with the bellows or reservoir
by cords, as in the former modifications, or may be actuated by stop batons
and a lever arrangement; in this modification the cross division between bass
and treble may or may not be used. By means of these pallets a great
variety of tone is capable of being produced by opening the bass pallet the
sound emitted from both the bass and treble divisions of the instrument escape
at the bass opening, thus producing a powerful bass with a soft treble, and on
closing the bass pallet and opening the treble one a soft bass with a powerful
treble is produced, while when both pallets are opened, the full power of the
instrument can at once be produced.
Another modification of swell box is that shown in half plan and horizontal
section, Figure 5, Sheet 1; this box is intended to be placed upon the divided
reed chest, Figure 6, in which the bass and treble portions are separated by
the longitudinal division A, shown in dotted lines. The position of the two
sets of reeds in this Figure are delineated by the dotted lines B and B¹,
situated at alternate sides of the front and back portions of the chest: pallets C
are shown at the extremities, of the reeds with their levers D moveable in the
lever rest or rack E. The swell box, Figure 5, to fit over this reed chest
has four pallets A, by means of which, coupled with the divisions contained

page_text: in it, the sound is modified to any extent from the softest and apparently most
distant sound to the full power of the instrument. This arrangement being a
modification of that herein-before described and more particularly referred to,
need not be more fully specified, as it is evident by the general arrangements
of this swell box and reed chest shown in Figures 4 and 5, Sheet 1.
Another modification of swell box is that shown in Figures 2 and 3,
Sheet 2, of which Figure 2 is a general plan, and Figure 3 a transverse
section taken through the treble half of Figure 2. In this arrangement the
box is divided horizontally by the sound board A. Figure 3, and vertically in
the lower half by the divisional strip B, shown in dotted lines, Figure 2, thus
separating the bass from the treble, whilst that portion between the sound
board and top of the box is divided by the diagonally situated portion C,
Figures 2 and 3. In the sound board two openings D and E are formed
one in each half at alternate sides, whilst pallets F and F are placed over
openings in the lid or cover alternating with the openings D and E. This
last-mentioned arrangement corresponds very closely with that described in
reference to Figure 2, Sheet 1. the difference, which is slight, chiefly con-
sisting in the constructive detail.
It is obvious that most of the foregoing arrangements of swell boxes can
be applied to harmoniums of ordinary construction already in existence, when
nearly the same improved effects are produced as in an instrument originally
made with my Invention applied thereto.
Having now described the nature of my said Invention, and the manner in
which the same is or may be used or practically carried into effect, I would
observe, in conclusion, that I do not confine or restrict myself to the precise
details or arrangements herein-before described and referred to, as many
variations may be made therefrom without deviating from the true principles
or main features of my said Invention; but what consider to be novel and
original, and therefore claim as the Invention secured to me by the herein-
before in part recited Letters Patent is,-
First, the arrangement and construction of musical instruments, substan-
tially as herein-before described. or any mere modification thereof.
Second, the arrangement and construction of reed chests in two divisions
with the bass and treble set of reeds separated for the purpose of producing a
subdued or loud tone independently, substantially as herein-before described
and shown in the accompanying Drawings, or any mere modification
thereof.
Third, the arrangement and construction of swell boxes with or without

page_text: divisions, substantially as herein-before described, or any mere modification
thereof.
Fourth, the system or mode of connecting the swell box pallets with the
wind reservoir, substantially as herein-before described, or any mere modifi-
cation thereof.
In witness whereof, I. the said James Gilmour, have hereunto set my
hand and seal, this Tenth day of January, One thousand eight
hundred and sixty-five.
JAMES GILMOUR. (L.S.)