UVEMENTS IN INSTRUMENTS FOR ASSISTING THE SENSE OF HEARING
Year: 1860

page_text: Glasgow, North Britain, Gentleman, for the
vention or
UVEMENTS
IN INSTRUMENTS FOR ASSISTING THE SENSE OF HEARING."-A communication
from abroad by Charles Grafton Page, of Washington, in the District of
Columbia, in the United States of America.
Sealed the 22nd March 1861, and dated the 26th December 1860.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on
the 26th December 1860.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of 166, Buchanan Street, in the City of Glasgow, North
Britain, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN INSTRUMENTS FOR ASSISTING THE SENSE OF HEARING," a com-
munication from abroad by Charles Grafton Page, of Washington, in the
District of Columbia, in the United States of America, to be as follows:-
This Invention relates to a peculiar construction and arrangement of appa-

page_text: ratus for assisting the sense of hearing, and consists in the employment of
simple deflectors of sound, in the form of open-mouthed chambers, by preference
of a curved and conic section, applied in any convenient manner to the exterior
of the ears, so as to deflect the sound into the ear passage. By this apparatus
the "roar" or continued murmuring sound attendant upon the use of the
ordinary ear tube or trumpet, having one end inserted into the ear is pre-
vented. These deflectors may be fitted to a spring bow placed over the top of
the head, or they may be made to form part of a hat, bonnet, or other head
dress.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on
the 26th June 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
and of 166, Buchanan Street, in the City of Glasgow, North Britain,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of December, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-fourth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said John Henry Johnson, Her special license that I, the said John Henry
Johnson, my executors, administrators, and assigns, or such others as I, the
the said John Henry Johnson, 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 "IM-
PROVEMENTS IN INSTRUMENTS FOR ASSISTING THE SENSE OF HEARING," a com-
munication from abroad by Charles Grafton Page, of Washington, in the
District of Columbia, in the United States of America, upon the condition
(amongst others) that I, the said John Henry Johnson my executors or
administrators, by an instrument 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

page_text: 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 John Henry Johnson, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
the following statement, reference being had to the accompanying Drawings
and to the letters and figures marked thereon, that is to say :-
The said Invention relates to a peculiar construction and arrangement of
apparatus for assisting the sense of hearing, and consists in the employment of
simple deflectors of sound, in the form of open-mouthed chambers, by preference.
of a curved and conic section, applied in any convenient manner to the exterior
of the ears, so as to deflect the sound into the ear passage. By this apparatus:
the "roar" or continued murmuring sound attendant upon the use of the
ordinary ear tube or trumpet, having one end inserted into the car is pre-
vented. These deflectors may be fitted to a spring bow placed over the top of
the head, or they may be made to form part of a hat, bonnet, or other head
dress.
And in order that the said Invention may be fully understood, I shall now
>proceed more particularly to describe the same, and for that purpose I shall
refer to the several Figures on the Sheet of Drawings hereunto annexed,
the same letters of reference indicating corresponding parts throughout all the
Figures.
Figure 1 represents a perspective view of the improved apparatus or instru-
ment; Figure 2 is a longitudinal section of the same; Figure 3' is a front
elevation of the instrument; Figure 4 is a back elevation of the same attached'
to a spring bow for holding it in its place; and Figure 5. represents the mode
of applying or wearing the instrument.
A, B, and E, Figures 1, 2, and 3, indicate the general contour of the
instrument, which is represented full size as used. The deflector A. should-be
constructed on the principle of a conic section, and such as to prevent as much
as possible repeated reflections in the instrument itself, or between it and the
head and parts of the ear, as the "roar" so objectionable in other devices is
due to repeated reflections or reverberation.
A variety of forms will suffice to deflect vibrations in such a manner as to
augment sound, but there are certain characteristics essential to the best
effects to obviate the "roar," so as to enable the ear to discriminate sounds,
and one which may be best understood by common phrase is the " open:
flare,

page_text: which obviates double reflection or reverberation. It is also of importance
that the deflecting surface terminate in conformity with the line of the
cartilaginous ridge, which circumscribes the central opening of the ear, so as
to prevent the passage or escape of aerial vibrations beyond that line, for that
in fact is the natural limit of the sound-gathering function of the external ear.
It is also important that all aerial vibrations from behind should be intercepted,
and that the instrument should be so constructed as to close well upon the ear
behind, so as to intercept interfering sounds, and insure the reflection of
vibrations from before, and deflect them to the external meatus. The main
portion A of the deflector is represented by a conic section, but for the purpose
of complete reflection to the external meatus the deflector takes a curvilinear
form at or about the part E (Figures 1 and 2). A plain surface in lieu of
the curved surface would have a good effect, but not so good as that of the
curved surface at this point. The chamber B is of the general outline form of
the ear, and is designed to enclose or surround it completely when the instru-
ment is in use, it being also adapted on the edge at n to the form of the head
at that part. The chamber B may be dispensed with, and the deflector fitted
to cover the ear-from-behind, thus simplifying the construction, but at some
little sacrifice of the efficiency of the instrument. The deflector may (especially
under the latter form), be worn in almost any position with its open or flaring
portion in front, up, down, or directly backwards, which latter position gives a
good effect. The deflectors are held in their places on the head by the spring
bow F (Figure 4), and this bow may be adjusted so as to fit different heads
and also to adapt the deflectors to their proper position. The deflectors may,
however, be so adapted to the form of the ear as to keep their places without the
aid of the bow, but the bow is preferable as a means of keeping them steady.
They can also be attached to a hat or cap or bonnet; or the rim of the bat or
cap may be made of suitable form and material to answer the purpose of the
deflectors; or plates of metal or other material may be worked into or concealed
in the sides of a bonnet, and so adjusted as to act like the deflectors herein-before
described, care being only necessary to give them their proper position. These
deflectors may be made of any firm material, and for the sake of lightness and
strength the material known as "hard rubber" is very serviceable. They can
also be made of metal, glass, horn, shell, papier maché, wood, or of any
material suitably firm, and can be ornamented to suit the taste.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe in conclusion that what I consider to be novel and

page_text: original, and therefore claim as the Invention secured to me by the herein-
before in part recited Letters Patent is,―
First, the general construction and arrangement of apparatus for assisting
the sense of hearing, as herein-before described.
Second, the combination of the apparatus for assisting the sense of hearing,
with coverings for the head, as herein-before described.
In witness whereof, I, the said John Henry Johnson, have hereunto set
my hand and seal, this Twenty-sixth day of June, One thousand
eight hundred and sixty-one.
J. HENRY JOHNSON. (L.S.)