MENTS IN VIOLINS AND OTHER STRING MUSICAL INSTRUMENTS
Year: 1885

page_text: 14
I, ISIAH GLAZEBROOK of Chattaway Street, Birmingham, in the County of
Warwick, Engineer, do hereby declare the nature of said invention for IMPROVE-
MENTS IN VIOLINS AND OTHER STRING MUSICAL INSTRUMENTS," to be as follows:-
.
My invention consists in constructing violins and other string musical instru-
ments such for example as violincellos, double bass and guitars as hereinafter
described, whereby the pitch or tone of the instrument is greatly improved by the
wave sound being increased in velocity; and my said invention consists in inter-
posing between the belly and the back of the instrument (in the case of a violin)
a secondary sounding board, which constitutes a double belly which is supported by
suitable sound posts. By so arranging an intermediate sound board, the physical
character of the instrument is changed, which determines a higher rate of vibration,
and consequently a louder and more melodious sound.
For convenience of description I will describe my invention in connection with
a violin.
Within the violin, that is, between the belly and the back of the instrument, a
central board or vibrating medium is disposed, which constitutes a double belly
which follows the contour or shape more or less of the instrument; that is, the
board described is supported or attached to the sides of the instrument at or about
the upper and lower bouts, or corners leaving a space between the inner sides of
the instrument other than at the points of attachment or suspension. This inter-
vening sounding board does not lie parallel with the belly of the instrument proper,
but is preferably slightly inclined downwards, from the neck or shoulder to the
other end of the instrument. This inclination gives the sonorous waves different
rates of vibration-Supporting sound posts are disposed between the intervening
sound board and the inside surface of the belly and back of the instrument, so as
to make the centre board or double belly perfectly firm and also to convey to the
board the vibrations created and passed through the bridge. By constructing
instruments as described, the vibrations of both the inner board, belly, back and
sides of the instrument are at the same time displacing the sonorous air waves
through the f holes at a more rapid rate than in instruments heretofore constructed.
I also cut f holes at the back of the instrument to facilitate the putting in of the
supports or sound posts.

page_text: The intervening or secondary sound board instead of being plain may be corru-
gated or concave or convex in cross section, or further, it may be hollowed out or a
wave like undulatory character given to it. Or the secondary sound board may be
made in the form of a box with open ends fixed on the inside of the back of the
intrument. The secondary or intervening sound boards described, may be pierced
with holes in any desired way.
ISIAH GLAZEBROOK.
By Henry Skerrett,
6, Livery Street, Birmingham,
Agent to the Applicant.
COMPLETE SPECIFICATION.
Improvements in Violins and other String Musical Instruments.
I, ISAIH GLAZEBROOK of Chattaway Street, Birmingham in the County of
Warwick, Engineer, do hereby declare the nature of said invention for "IMPROVE- 1
MENTS IN VIOLINS AND OTHER STRING MUSICAL INSTRUMENTS," and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement:-
My invention consists in constructing violins and other string musical instru-
ments such for example as violincellos, double bass, and guitars as hereinafter
described whereby the tone of the instrument is greatly improved; and my said
invention consists in interposing between the belly and the back of the instrument
(in the case of a violin) a secondary sounding board, which constitutes a double
belly and is supported by suitable sound posts.
By so arranging an intermediate sound board, the musical character of the instru-
ment is improved thus; determining a higher rate of vibration, and consequently a
louder and more melodious sound.
For convenience of description I will describe my invention in connection with
a violin.
Within the violin; that is, between the belly and the back of the instrument, a
central board or vibrating medium is disposed, which constitutes a double belly
which follows the contour or shape more or less of the instrument; that is, the
board described is supported or attached to the sides of the instrument at or about
the upper and lower bouts or corners leaving a space between the inner sides of the
instrument other than at the points of attachment or suspension-This intervening
sounding board does not lie parallel with the belly of the instrument proper, but is

page_text: preferably slightly inclined downwards, from the neck or shoulder to the other end
of the instrument. This inclination gives the sonorous waves different rates of
vibration.
A sound post is placed between the intervening sound board and the inside
surface of the belly and back of the instrument, so as to make the centre board or
double belly perfectly firm and also to convey to the board the vibrations created
and passed through the bridge. By constructing instruments as described, the
vibrations of both the inner board, belly, back and sides of the instrument are at
the same time displacing the sonorous air waves through the holes at a more rapid
rate than in instruments heretofore constructed-I also cut ƒ holes at the back of
the instrument to facilitate the putting in of the supports or sound posts.
The intervening or secondary sound board instead of being plain may be corru-
gated or concave or convex in cross section, or further, it may be hollowed out or a
wave like undulatory character given to it. Or the secondary sound board may
be made in the form of a box with open ends fixed on the inside of the back of
the instrument. The secondary or intervening sound boards described, may be
pierced with holes in any desired way.
I will now proceed to describe with reference to the accompanying Drawings the
manner in which the same is to be performed.
Figure 1 represents in longitudinal vertical section a violin provided with
improvements made according to my invention-Figure 2 is a plan of the saine,
with the back cover removed, in order to exhibit the intermediate sounding board
which is placed between the belly and the back of the instrument. The said
figure 1 is taken on the dotted lines A B figure 2. Figure 3 is a cross section
taken on the dotted lines C D figure 2.
The same letters of reference indicate corresponding parts in the several figures.
a is the belly, and b is the back of the instrument. c is an intermediate sounding
board or double belly placed in an oblique direction within the body of the instru-
ment; that is, between the belly a and back b of the instrument, a central sounding
board or vibrating medium is disposed, which said medium constitutes a double
belly, as best seen in figures 1 and 2. The said double belly or sounding board
preferably follows the contour or shape more or less, of the instrument, leaving
rests or supports c², by which the sounding board is suspended or fixed within the
body.
This intervening sounding board is preferably inclined downwards from the neck
to the tail piece, as best seen in figure 1. This inclination imparts to the sonorous
waves, different rates of vibration. The transverse section of the board is prefer-
ably thicker at the treble side than at the other as seen in figure 3. d is a sound
post placed between the intervening sounding board c and the underside of the
belly a. e² are supports between which the sounding board is clamped or fixed,
thus making the same firm and rigid. f are also supporting posts placed between
the underside of the second belly, and the back of the violin. g is the tail piece of
the instrument, and h the bridge.
By constructing instruments as described, the vibrations of the intermediate
sounding board, belly proper, back and sides of the instrument are at the same time
displacing the sonorous air waves through the f boles at a more rapid rate than in
instruments heretofore constructed.
Figure 4 represents in plan, and figure 5 in longitudinal section, a secondary
sounding board provided with a strengthening rib running diagonally.
Instead of the sounding board being extended from the neck to the tail piece as
in figures 1 and 2, a disc i may be substituted therefor (see figures 6 and 7) which
disc is elevated above the back of the instrument by open work supports 12. The
sound post d down which the sound travels from the bridge, is disposed between
the belly and disc or plate sounding board-The disc or plate may be round,
elliptical or any other suitable shape.
Figure 6 is a longitudinal section, and figure 7 is a plan. In the latter the disc
is shown in dotted lines.

page_text: Figure 8 shows a violin with an open back. In this modification, the sounding
board placed between the belly and the back, forms the top to the box like
enclosure j. The said open back is provided with a cross bar k. The sound
travelling from the bridge down the sound post to the intermediate sounding
board m, is vibrated through. the apertures or holes made in the back of
the instrument, as best seen in the underside view figure 9.
In some cases the bar may be dispensed with, leaving a portion of the back
entirely open.
In figure 10 the sounding board or medium is made in the form of a conical or
taper box open at its ends and marked n; that is, the sounding medium is made
in the form of a conical enclosure open at its ends, so as to give the proper
dispersion and concentration of sound."
Figure 11 is a cross section on the dotted lines E F figure 10.
The sound post is placed between the conical sounding board or sound box, and
between the belly of the instrument in the same relative position as before
described, as seen in figure 11.
Although I have described and represented in figure 1 that the sounding
board is disposed obliquely or arranged diagonally with regard to the body of
the instrument, yet I wish it to be understood that the said sounding board
may be disposed in any other desired direction.
By constructing instruments as herein before described, the tone and quality of
the sound emitted is greatly improved, by enlarging or increasing the sound or
vibrating surface.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
First. Disposing or placing within the body of a violin or other like string
musical instrument, a secondary sound belly or intervening sounding board
marked c for increasing and improving the tone of the said instruments, sub-
stantially as described and illustrated in figures 1, 2 and 3 of the accompanying
.Drawings; also the modifications as described and illustrated in figures 6, 7,
10 and 11.
Secondly. In an open back string musical instrument in which the top m of
the box or enclosure; constitutes the sounding board, substantially as described
and illustrated in figures 8 and 9 of the accompanying Drawings.
Dated this thirty first day of October 18851
ISAIAH
GLAZEBROOK.
By Henry Skerrett,
6, Livery Street, Birmingham,
Agent to the Applicant.