CERTAIN IM- PROVEMENTS IN THE TRANSMISSION AND EMISSION OF AIR AND SOUND
Year: 1853

page_text: LETTERS PATENT to Hezekiah Marshall, of Canterbury, in the
County of Kent, Architect, for the Invention of "CERTAIN IM-
PROVEMENTS IN THE TRANSMISSION AND EMISSION OF AIR AND SOUND
Sealed the 30th March 1858, and dated the 7th January 1853.
PROVISIONAL SPECIFICATION left by the said Hezekiah Marshall
at the Office of the Commissioners of Patents, with his Petition,
on the 7th January 1858.
I HEZEKIAH MARSHALL, of Canterbury, in the County of Kent,
Architect, do hereby declare the nature of the said Invention for
"CERTAIN IMPROVEMENTS IN THE TRANSMISSION AND EMISSION OF AIR AND
SOUND" to be as follows:
My Invention is intended to be applied to buildings and to certain
kinds of musical instruments, and consists in the adaptation and
formation of apertures in a part or parts of the building, or of the
musical instrument, for the admission of air in several streams into a
kind of chamber, whence it is discharged at a single outlet.
My Invention is carried into effect in buildings by forming several
apertures in the ceiling or other part of the building, through which
the air may pass into a chamber between the ceiling and the roof;
then an outlet is formed in this chamber, consisting of a channel or

page_text: passage for conducting the air upwards within a tower or other erec-
tion, and so discharging it into the atmosphere. By this means a
double effect is produced in the interior of the building (a church for
instance), viz., a means of transmitting sound & producing ventilation,
care being taken to provide suitable means of ingress for the external
air. In buildings in which there is no ceiling underneath the roof an
artificial ceiling may be formed. The number, situation, and size of
the apertures may be varied in different buildings. Also, in case of
applying the Invention to the ceiling of a room having rooms over it,
the space between the ceiling of the room and the floor of the room
..over it might be employed as the chamber for receiving the air to be
discharged, through a channel or passage carried upwards outside the
building. In applying the Invention to piano-fortes (particularly
. upright ones) the apertures (ornamental in appearance) may be dis-
tributed over the front of the instrument, and a chamber for the
admission of the air through the said apertures, and its exit t
single outlet, may be formed on the top of the instrument.
I also adapt the Invention to musical boxes, by inclosing the box in
an ornamental case having apertures formed in the lower part of it,
and a single outlet at the top. And my Invention may be adapted to
violins, violincellos, and guitars, by forming a number of apertures in
the back or under part of the instrument (instead of those at present
formed in the front or upper part) for the admission of air, and making
the part to which the finger board is applied hollow, with a single exit
channel or passage for the air.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Hezekiah Marshall in the Great Seal Patent
Office on the 7th July 1858..
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
HEZEKIAH MARSHALL, of Canterbury, in the County of Kent, Architect,
send greeting.
WHEREAS Her Most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of January, in the
year

page_text: of our Lord One thousand eight hundred and fifty-three, in the six-.
teenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Hezekiah Marshall, Her special
license that I, the said Hezekiah Marshall, my executors, administra-
tors and assigns, or such others as I, the said Hezekiah Marshall, my
executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdon of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for
"CERTAIN IMPROVEMENTS IN THE TRANSMISSION AND EMISSION OF AIR AND
SOUND," upon the condition (amongst others) that I, the said Hezekiah
Marshall, by an instrument in writing under my hand and seal, 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 Hezekiah Marshall, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the Drawings here-
unto annexed, and to the letters and figures marked thereon (that
is to say):
My Invention of "Certain Improvements in the Transmission and
Emission of Air and Sound" has for its object the means of regulating
the passage of the air admitted into buildings, and certain kinds of
musical instruments, in such a manner as to produce in buildings ven-
tilation without downward draught, and also the diffusion of sound over
their interior space with increased clearness, and in musical instruments
the issue therefrom of an increased volume of sound.
And this effect is produced by admitting the external air into the
building (or the air of the room into the musical instrument), by means
of a sufficient number of apertures suitably distributed, then trans-
mitting the air so admitted to one place of emission or exit.
In order, however, that my Invention may be fully understood, I -
will proceed to describe it more particularly; first, in its application to

page_text: buildings; and, secondly, in its application to certain kinds of musical
instruments.
With reference to buildings: Although one form and arrangement of
the edifice may present more facilitics than another for the application
of my Invention, yet it may be adapted, with more or less benefit, to all
forms in which these general features of arrangement may be carried
into effect, (viz.) the admission of the air at the floor, or as low as con-
venient; its transmission from the various parts of the interior space to
one common chamber above the ceiling; and its emission or exit through
a passage or passages at a higher elevation than the said chamber.
1 will now describe my Invention as applicable to churches. The
form of church to which I consider it best adapted is the cruciform
church, with a tower, or tower and spire, at the west end, and a lofty
arch opening from the tower into the nave; but the Invention is by no
means confined to this form of church. The floor of the church, or a
portion of it, should be raised above the ground, so as to allow the
external air to enter through openings let into the floor, and supplied
with valves to regulate the admission of the air, but this is no part of
my Invention. The air is to be admitted at the floor in any way that
is found most efficient; then, under my Invention, the air so admitted is
carried to a chamber or space between the ceiling and the inside of the
roof. The form of roof which I prefer for the purpose is the open
timbered roof, which may be either boarded or plastered, either on the
top of the rafters or on the under side and across the "collars," the
latter being not lower than one third of the depth of the roof. It is
desirable that this form of roof should surmount the nave, transepts, and
chancel, so as to constitute, by means of suitable channels of communi-
cation, one continued chamber to receive the air and sound from the
interior of the church. There should be no outer openings in the
gables by which the external air can enter this chainber, but an outlet
should be formed at the end of the chamber next the tower, through
which the air and sound may pass into the upper part of the tower or
spire, and find its exit in an elevated part of the same. But the
arrangements thus referred to will be more clearly understood from the
following description of the accompanying Drawing.
Fig. 1, is a longitudinal section of a church. a, a, is the floor, with

page_text: ventilators b, b, suitably distributed; c, c, is the ceiling or "collars;"
d, d, the roof; e, e, the chamber for the sound; f, a means of communi-
cation between the chamber in the chancel and that in the nave; g, the
apertures leading from the hudy of the church into the chamber; h, the
outlet for the air and sound from the chamber e, into the tower; 2,
the exit passage for the same in the upper part of the spire.
Figs. 2, 3, and 4, represent in vertical section on an enlarged
scale three different forms of the apparatus or instrument required to be
placed over the apertures 9, 1, in order to prevent downward draught.
also to facilitate the conveyance of the sound into the chamber e. This
apparatus or instrument (shewn at k, k, in Fig. 1,) is placed over
cach of the apertures g. 9, the aperture being hoppered over with deal,
and the instrument fixed over the mouth of the hopper. It will be seen,
on reference to Figs. 2, 3, and 4, that the air and sound entering the
same at the bottom of the instrument will be conveyed in the direction
shewn by the arrows, and is prevented from returning by the arrange-
ment of the blades 7, 1, which may be variously formed, provided they be
suitably arranged to intersect the line of the downward draught, as shewn
in the Figures. This instrument may be constructed of different
materials, but from my present experience I prefer wood.
The operation of my Invention is as follows:-A suitable quantity of
external air being admitted through the ventilators b, b, or otherwise,.
into the interior of the building, this with the sounds therein become.
diffinsed over the same, and pass through the apertures g, g, and the
instruments, into the chamber e, whence they are prevented from
returning, and are allowed to pass into the tower at h, whence they are
emitted at the elevated part i, whether this be at the spire, as shewn in
Fig. 1, or at the tower, or, where there is no tower or spire, at any other
erection. It is desirable also that the floors, trap door, &c. in the tower
should have apertures in them, as at m, m, in order to increase the
draught towards the clevated point i. The number of apertures g, in
the ceiling or "collars" c, may be varied, and they may be covered
with plain or ornamental perforated screens adapted to the style of the
building. And it may be observed, that in churches in which there is
no coiling underneath the roof, an artificial ceiling may be formed.

page_text: I would herc remark that my Invention may be adapted and applied
to buildings of other forms, such as halls, theatres, &c.; but I need not
describe them particularly, as it will be readily understood that the
essential principle of the Invention as above described may be adapted
to suit various kinds of buildings, whether existing or to be erected. I
will, however, describe the mode of its application to rooms which have
other rooms over them. In this case, the air being admitted into the
room by any suitable means is conveyed through apertures in the
ceiling into a chamber formed between two joists of the floor, the outlet
from the chamber leading to some outer wall and partition, and being
carried up outside the building in the form of a pipe or within a fluc or
channel formed in the outer wall; an instrument, as represented at
Figs. 2, 3, and 4, and described above, being fixed over the opening at
the top of such pipe or channel. In order to form the chamber for the
air and sound I nail inch fillets to the two joists, and upon these a
three-quarter inch deal board to form the top of the said chamber, the
sides and bottom being formed by the two joists and the ceiling of the
room underneath.
I proceed now to describe my Invention in its application to certain
kinds of musical instruments. In applying the Invention to piano-
fortes (particularly upright piano-fortes), the apertures for admitting the
air into the sound chamber may be suitably distributed at the lower
part of the nstrument and the chamber formed behind the strings, the
sound therein collected being discharged at a single outlet formed in an
ornamental case on the top of the instrument.
In applying the Invention to musical boxes the mechanism is enclosed
in an ornamental sounding case, having several apertures in the lower
part of it, and a single outlet at the top.
And in applying iny Invention to violins, violincellos (bass and double
bass), and guitars, I form a suitable number of apertures in the back or
under part of the instrument (instead of those at present formed in the
front or upper part), the ordinary hollow part of the instrument itself
forming the sound chamber, and I make a hollow channel along the
handle or finger-board, from which the sound is discharged at a single
outlet, which I prefer to be in the form of a trumpet mouth.

page_text: In adapting my Invention to existing instruments, it would be neces-
sary to close the present openings, but, if preferred, these may be repre-
sented in their usual place by slightly indenting the surface, also by
darkening the wood at such parts.
I would remark, that in all the musical instruments above referred to
my Invention is not confined to any particular form or size of instru-
ment, the number and distribution of the apertures being varied
according to the character of the instrument.
Having thus described the nature of my Invention, and in what
manner the same is to be performed, I would have it understood that I
do not mean or intend to confine myself to the precise forms and
arrangements above described; neither do I claim as of my Invention
the mode of admitting external air into buildings above referred to, nor
anything relating to musical instruments except as herein-after men-
tioned. But what I do claim as of my Invention is in respect of
buildings, the transmission of air and sound (air being previously
admitted) into a chamber through openings covered by instruments.
proventing the return of the same, and the emission of the same at a
single outlet in an elevated part of the building as described. And in
respect of musical instruments, I claim the adaptation and application of
the same principle of transmitting the air and sound to a chamber, and
emitting them from a single outlet as described. .
In witness whereof, I, the said Hezekiah Marshall, have hereunto
set my hand and seal, this Sixth day of July, in the year of our
Lord One thousand eight hundred and fifty-three.
Witness,
WILLIAM SPENCE,
Patent Agent.
HEZEKIAH MARSHALL. (L.S.)