AN INSTRUMENT FOR TURNING THE LEAVES OF MUSIC BOOKS IN A SIMPLE AND EFFECTIVE MANNER, WITH OR WITHOUT PEDAL WORK ATTACHED
Year: 1818

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, .I, JOHN
CHANCELLOR; of Sackwell Street, Dublin, Watch Maker, send greeting.
WHEREAS His most Excellent Majesty King George the Third did; by
His Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland; bearing date at Westminster, the Twenty-first day of
November, in the fifty-ninth year of His reign, give and grant unto me;"
the said John Chancellor, my exors, admors, and assigns, His especial licence,
full power, sole privilege, and authority, that I, the said John Chancellor,
my exors, admors, and assigns, during the term of years therein mentioned,'
should and lawfully might make, use, exercise, and vend, within England,
Wales, and the Town of Berwick-upon-Tweed, my improved method of "AN
INSTRUMENT FOR TURNING THE LEAVES OF MUSIC BOOKS IN A SIMPLE AND
EFFECTIVE MANNER, WITH OR WITHOUT PEDAL WORK ATTACHED;" in which said
Letters Patent there is contained a proviso, that if I, the said John Chancellor,
shall not particularly describe and ascertain the nature of my said Invention,
and in what manner the same is to be performed, by an instrument in
writing under my hand and seal, and cause the same to be inrolled in His
Majesty's High Court of Chancery within six calendar months next and
immediately after the date of the said Letters Patent, that then the said
Letters Patent, and all liberties and advantages whatsoever thereby granted
shall utterly cease, determine, and become void, as in and by the same,
relation being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
John Chancellor, do hereby declare that my said Invention, and the parts of
which it is combined, with the method of applying them, is shewn in the
Drawings and description annexed, which are as follows:-
Drawing 1, Fig. 1st, a represents a plan of a brass arbor or axis fixed to
the brass piece A, A; 6 represents a small projecting hook, which enters a
small slit in a spiral spring, the said spring being inclosed in a brass barrel
exactly similar to those used as the mainsprings of watches; upon the arbor a
is placed a ratchet wheel, as will be shewn hereafter, which is kept in a proper
position by the click spring c, the small projecting stud shewn at c falling into
the space between the teeth; this stud c is formed with two inclined planes in
opposite directions, but the end where the two planes meet is rounded off, so as
to permit the ratchet wheel to pass in either direction when a proper force is
applied, namely, sufficient to lift the click out of one space and permit it to
drop into another upon the arbor a; the whole of the parts are placed or fixed;
and when so combined, the brass piece A, A, is fixed to a mahogany frame or
desk by screws that pass through the holes A, A.
Fig. 2 represents a front elevation of the arbor and brass piece, in which
Figure the length of each part of the arbor may be seen, and also the variation
in point of size that is necessary for the reasons hereafter to be explained."
d and e are two small short pins, which I call banking pins, these limit the
extent of motion of the ratchet wheel; their mode of action will be described
hereafter.
Fig. 3 represents a plan of the upper side of the brass piece A, A, and
ratchet wheel i combined; the ratchet wheel i is concentric with the circular
lever plate B; and is rivetted or screwed fast thereto; a hole through both per-
mits the arbor a to pass, upon which both the lever plate B and ratchet wheel
i turn partly round, but are prevented from performing a complete revolution
by the pins 1 and 2 in the ratchet wheel meeting the banking pins d and e; by
this contrivance the motion is limited either way when the lever plate and
ratchet wheel are moved. f. f, &c., represents seven levers, each of which
turns freely on steel centres screwed into the lever plate, their ends being seen
at h, h, &c.; on each side of these levers a small bar of brass is fixed, each of
them, turn upon the rivet that fixes it to the lever; the heads of the rivets may
be seen near the end of each bar; when these are turned in certain directions
they form a kind of fork to place the leaf of a book between, each leaf so
placed being securely held by the fork bars pressing towards each other.
Fig. 4 represents a combination of parts, from which Fig. 3 may be
supposed to have been removed, or lifted off and laid down, as shewn in Fig. 3.

page_text: C represents a brass wheel with four arms, the edge of this wheel is grooved
like a pulley to receive a small cord, which is used to give motion to the
wheel; this wheel is pressed towards the right hand by a spiral spring coiled in
a small barrel, the barrel being fixed to the centre of the wheel by the screws
3, 4; the inner coil of the spring that hooks upon the hook b' of the arbor a,
Fig. 2, is seen at k; in the centre of the wheel 5 and 6 are two pump detents, .
which are fixed to the ends of the spring D and E, these springs are screwed
to the arms of the wheel C, the ends of the screws been seen at F, G. IÌ
represents a lever; which turns upon the screw seen at H; represents a
small steel pin screwed into the lever H, the use of this pin is as follows:-
When the wheel C'is turned partly round by its cord, the pin 7 presses against
a fixed projecting arm, seen at m, Fig. 5, which causes it to turn upon the
screw H, and the end n depresses the spring D and detent 5 by its motion or
passage over the stud p, the upper part of which is formed into an inclined
plane for that purpose; by this contrivance the detent 5 may be depressed at
any convenient time for the purpose of passing under a lever, the use of which
will be hereafter explained. The spring r serves to return the lever to a proper
position, the same being limited by the pin bearing against the arm of the
wheel C; 9 represents a piece of brass fixed to the rim of the wheel C, having
an inclined plane at each end, this is used to elevate and depress a small spring
detent, seen at s, Fig. 5; 1 represents a locking bolt which turns or moves
upon the screw at I; the under part of the end 10 is an inclined plane, the
parts of the detents marked 7 and 8 being likewise formed into inclined planes
enables the end of the locking bolt to slide easily over them, and by so doing
both the detents 5 and 6 will be lowered or pumped down, so as to let all the
levers fixed to the lever plate B, Fig. 3, pass over them collectively.
Fig. 5 represents the, under side of the lever plate B, with the levers attached
by the screws h, h, &c., as before described. Upon the arbor a the lever plate is
placed, and immediately over it the washer u, upon which is placed the collet
w, x; this collet is made fast to the arbor a by a small screw, which prevents it
from turning round upon the arbor; the brass wire arm m is tapped into the
neck of the collet, and the detent s is fastened to the rim by a screw and steady
pins; a portion of the flat rim of the collet is filed away, so that the two pro-
jections w and x may be used as embankments to limit the motion of a small
stud or pin, seen at y, Figs. 4 and 5; a small pin is shewn in dotted lines near
a, this passes through the arbor and serves to bind the washer u in a proper
position.
Fig. 6 represents the wheel C, with the same parts combined as shewn in
Fig. 4, but this Figure shews the under side turned upwards. I shall also observe

page_text: that this Figure may be supposed to have been lifted off Fig. 5 and placed by
its side, observing that the pin y, that projects a. little way below the under
surface of the wheel, as it now lays; should be placed between the embanking
projections of the collet, shewn at w, a, Fig. 5; the two ears that serve to fix
the barrel z, and the spiral spring contained therein, are shown at 3 and 4.
Fig. 7 shews a plan at the. collet w, x, separated from the principal arbor.
This Figure is given to shew the exact position of the brass arm m, and the
spring detent s; likewise the screw that passes through the pipe of the collet to
fix it to the arbor, as before described.,
Fig. 8 represents a side view or elevation of the same parts. In, this
Figure, the shape at the small stud at the end of the spring s may be better
seen, the said stud having on one side an inclined plane to permit the return of
the levers to their original position after, they have been used by, the performer.
Fig. 9 is a plan of the washer w, and Fig. 10 is an edge view...
Fig. 11 is a plan of the barrel cover, and its pin that passes, through the
arbor a.
Fig. 12 is a section of the same cover.
Fig. 13. is a side elevation of one of the levers, with its two forked bars,
both of which are elevated, to shew how they may be turned.upon their rivets
so as to place a leaf of a book between them.
Fig. 14 and 15. shew a front and side view of the left-hand lever. detent
stud; these shew the incline plane at 8 and the form of the projecting pin 5..
Figs. 16, 17, 18, shew. the three external sides. of the right-hand, lever
letent stud; the inclined plane 7 and projecting part 6 are plainly seen... The
whole of these figures been drawn upon a magnified scale.
Figs. (19) and (20) represent a front and side view of the stud p fixed.to
the spring (D) in Fig.. (4), likewise magnified for the purpose of explanation.
Having enumerated all the individual parts, I shall now endeavour to shew.
how they are to be combined in the most effective manner. The ratchet
wheel i being rivetted to the lever plate B, is placed upon the arbor (a), and
the click (c) placed between two teeth as shewn in Fig. (3,) always observing
to place the two pins on the ratchet wheel between the banking pins d and e,
fixed in the brass piece a, a, Fig. (4); this being done, the washer (u) is to
be placed upon the arbor (a) and fixed by cross pin which passes through. a
hole in the arbor (a), and is retained in its place by friction. The position of
this pin is shewn in dotted lines at (a), Fig. (5); the parts so combined are
represented in Fig. (3); the collet w, a, Fig. 7, having the arm (m) and
spring (s) fixed as here shewn, is then to be placed upon the arbor (a), and
being pressed down upon the washer (u) is fixed immoveably to the arbor by

page_text: b
the steel screw that passes through the pipe of the collet; this combination is
seen at Fig. (5). These parts being united; the lever (H) is fixed to the
wheel (C) by the steel screw seen near (H), Fig. (4); this screw having a
plain neck enables the lever to turn or move upon it parallel to its own plane.
I shall suppose that the spring (r) has been fixed in its stud, and the strength
adjusted before the lever (H) is fixed, the barrel with its mainspring is then to be
fixed to the centre of the wheel (C) by the screws (3 and 4) as shewn in Fig. (6).
I shall also suppose the locking. bolt (I) and brass arc (9) as having been
previously fixed. The parts thus combined will appear like (4 and 5), except.
that those figures have got the locking détents and springs fixed, which should not
be done in this stage of the combination. The next operation is to place the
wheel (C) as combined in Fig. (6) upon the arbor a, and it will then rest upon
the surface of the collet seen at w, x, Fig. 5. I have before supposed Fig. (6)
to be lifted off or removed from Fig. (5); I now suppose it to be placed upon
it again, when, if things are properly placed, the arbor (a) will then be within
the inner coil of the spiral spring contained within the barrel, and then, if the
wheel C be turned in a proper direction, the hook 6 upon the arbor a will drop
into the slit in the mainspring. The wheel C must then be turned so as to
oppose the resistance of the spring, or as a workman would term it, the spring
must be set up, which may be done by turning the wheel either one or two
turns, according to the degree of force required. When a sufficient force is
thus obtained, the wheel C' must be so placed that the pin Y, being forced into
the small hole prepared for it, will stand somewhere between the two embank-
ments shewn on the rim of the collet w, x. If it be now permitted to choose a
position, the pin y will be pressed firmly against the embankment seen
at w, Fig. 5, consequently its motion will be limited to the space contained
between the two embankments wand x. The barrel cover is next to be put
on and fixed by its cross pin, as shewn at Fig. 11; also the screw pin / tapped
into the lever H must then be screwed in. And edge view of this lever, and
the length of the pin l, and likewise the pin v, will be seen in Fig. 21. The
locking bolt being drawn back, as shewn at 10, Fig. 4, the detent spring E, D,
may then be fixed by their screws F and G, as shewn in Fig. 6, after which
the cord K is fixed to the wheel C by being passed through a hole in the rim,
and confined therein by a knot at one end. The brass piece A, A, may then be
screwed to any convenient desk or frame, such as represented in Drawing 2,
Fig. 1. I shall now endeavour to shew how this instrument effects and per-
forms the operation of turning over the levers of music books without the
hand of either the performer or an assistant.
Fig. 22 represents a plan of the instruinent combined, and fit to be screwed

page_text: to any sort of desk or frame that may be considered most convenient, There
fore, if the brass piece A, A, is made fast to any suitable frame, the lever
plate B and ratchet wheel i may be moved from the right hand to the left,
until the pin in the ratchet wheel stops against the banking pin fixed on the
under side of the brass piece at d. It must be evident that that the levers
ff, &c. will be likewise turned with the lever plate, all of them being fixed
thereto; the whole may then be turned back again, until the pin 2 strikes
against the banking pin e fixed on the under side of the brass piece A, A. I
shall here observe, that when the levers and lever plate are moved in the
manner just described, the click c will be forced to slide over the points of the
teeth of the ratchet wheel, and fall by the force of its spring into the spaces
between the teeth alternately. From what has been stated, it must be evident
that this motion may be so conducted that the lever plate may be held
stationary at seven different points in its passage; these being the number
of spaces into which the click c drops in its passage from the right to left,
and vice versa.
"
Having before shewn how the mainspring and barrel are united to the
wheel C, it will be unnecessary to repeat it. I shall, therefore, now state that
the wheel C may be drawn round by the cord K, unless the locking bolt I
assumes the position seen at L, at which time-the pin 7, fixed in the lever H,
begins to bear upon the arm m, see Figs. 4, and 5, and 6; if the cord be now
slackened, the wheel will return to its original position, being forced thereto by
the action of the mainspring. From what has been said, it will be plainly seen
that both these motions, as far as they have been carried, proceed completely
independent of each other. But to effect this, the detents shewn at 5 and 6
are pressed down by the locking bolt I, the position of which is shewn when in
that state by the fragment, Fig. 23. These preliminaries being understood,
the action of the whole will be easily explained. The levers f, f, &c., being
moved with the lever plate, &c., to the right hand, the detents 5 and 6 being
previously locked down, the whole will appear like Fig. 22, except that, in this
Figure, the detents 5 and 6 are unlocked, and have the lever f 1 exactly between
them; if now the wheel C be pulled round by the cord K until the locking
bolt assumes the position shewn at L, the lever f 1 will be turned upon its
centre by the detent 6, and placed in the position shewn at m in dotted lines.
I shall now observe, that as this lever may be supposed to have a leaf of a
music book placed between the forks o and t, and that a part of that music
must be repeated, it will be necessary to return the lever and leaf to the
position from which it was moved; to do this, nothing more is necessary than
to loosen the cord K, and the action of the mainspring will immediately

page_text: return it to its original place. The motion that is effected by the peculiar com-
bination of these parts and agents, I call the da capo motion. It is, perhaps,
needless to add that this may be repeated as often as a proper degree of tension
is applied to the cord, whether it be by the use of the foot of the performer or
his knee, for either may be made to effect the purpose at the option of the
performer, who may choose to use this instrument. If it should not be
necessary to use the da capo motion as soon as the lever f 1 is brought to the
position shewn at m, a greater degree of force must be applied to the cord, by.
which means the wheel C will be carried further round until the lever f 1 and
the lever plate B are placed in the position seen at n, where it will be left, and
the detents 5 and 6 will be returned by easing the tension upon the cord,) to
convey in the same manner another lever, and so on till the whole are turned
over, if that be necessary. I shall now endeavour to explain what takes place
when the additional pressure is applied to the cord X, as before described :-
When this additional pressure is applied, the pin l, fixed in the lever H, see
Figs. 6, 4, and 21, comes in contact with the arm m, Fig. 5, and as that is
fixed immoveably to the collet w, x, the spring ŕ yields to the pressure given
upon the pin l, and permits the end n of the lever 'H to slide over the inclined
plane of the stud p, by which means the spring D is depressed, and with it the
detent stud 5; this, of course, disengages the lever that was before between the
two detents 5 and 6, and it drops by its gravity into its proper situation, the
whole frame and desk, and all the parts of the instrument, being placed so as to
incline backwards for that purpose. By means of the force applied to the
cord K, the detent stud 6 will press so firmly upon whichever lever it may be
in contact with, that it will force the lever plate to turn equal to one tooth of
the ratchet wheel, the click c raising out of one space and falling into another.
These movements will take place when each of the levers are passed or
turned over, and when the whole have been turned the locking detents must
be locked down by the locking bolt I, and then the whole the levers may be
returned to repeat their operations. The instant that the wheel C and
detents 5 and 6 begin to advance, the inclined plane at the end of the brass
piece q, Fig. 22, is forced under the spring S, and thereby raises the small
stud at the end, the flat side of which, coming up between the levers ƒ i
and f 2, retains f 2 in its place until the detents 5 and 6 return to receive it,
at which time the spring will have descended down the inclined plane, and
by that means deliver the lever which is retained into the power of the
detents 5 and 6.
Drawing 2 represents perspective view of the instrument fixed to a
common niusic desk or stand, the front framing of which is united to the back

page_text: one by brass hinges A, A, consequently the lower part may be advanced
forward, so as to place the back of the book or paper nearly in a line with the
arbor or axis of the instrument, the book or papers being kept in a firm position
by the spring shewn at B, which passes over the top and is made fast to a spiral
spring at the back; but this sort of desk or frame forms no part of my Inven-
tion, I have only introduced it to show how my instrument may be applied to
any kind of frame, desk, or stand; and with regard to the method of applying
the power to the foot or knee of the performer, it may be done by conducting
the cord to a pedal or lever, fixed to any part of a musical instrument or stand,
at the will or convenience of the workman or performer. In this perspective
view I have shewn only two of the levers, with their fork bars turned up; the
left-hand one I suppose to have been placed in that position, and that it may
the more plainly be seen, I have represented the leaf that it may have removed
as torn off, by which means the position of the forks on both sides may be seen,
the right-hand one shewing how each leaf is placed in the forks before the
instrument is set in motion; when the instrument is to be put away, the levers
should be all placed on the right-hand side, and the small guard C is then to
be placed in front, to confine them in that position and prevent accident. It
must appear evident that this instrument may be applied to an infinite variety
of stands or music desks, the method of doing which will and must be suggested
both by the workman and circumstances.
Now I hereby declare that this instrument that I have invented may be
made of any suitable metal or material, but, from experience, I prefer brass
and steel; and I shall here observe that, all the parts that are tinted blue are
made of steel, and all those parts that are made of brass are either tinted
yellow or left in outline; the brass for this purpose being well hammered,
especial those parts that are to act as springs.
The whole of the Figures upon Drawing 1 are drawn of the proper size
except Figures 14, 15, 16, 17, 18, 19, and 20, all of which are drawn upon
a magnified scale for the purpose of shewing the parts more clearly. I shall
I also observe that the number of leaves may be increased by increasing the
number of levers, and also the number of teeth in the ratchet wheel, but the
increase must in every case be in the same proportion both as to size and
number. To explain this more clearly, this instrument will turn seven leaves,
and there is twenty-one teeth in the ratchet wheel, and if the lever plate was
to have levers all round at the same distance as those represented it would
contain twenty-one also, therefore if eight levers are wanted the ratchet wheel
must be cut into twenty-four teeth, and if nine were wanted it must then
liave twenty-seven teeth, and so on to any convenient number, the lever plate

page_text: being divided in the same proportion, and the size or diameter of each increased
proportionally..
And, further, to prevent any infringment of this Patent, I hereby declare
that I have faithfully shewn both the principles and combinations that I make
use of, and likewise the construction of each and every individual part,
therefore whoever shall make use of either of the principles or combinations
herein described for the same identical purpose, namely, that of turning the
leaves of music books in a simple and effective manner, will to all intents and
purposes infringe upon this Patent.
In witness whereof, I, the said John Chancellor, party hereto, have
hereunto set my hand and seal, this Twenty-first day of May, in the
year of our Lord One thousand eight hundred and nineteen.
Inrolled the Twenty-first day of May, in the year of our Lord One
thousand eight hundred and nineteen.