IMPROVEMENTS IN APPARATUS USED IN COMBINATION WITH> ACOUSTIC INSTRUMENTS
Year: 1881

page_text: LETTERS PATENT to Frank Wirth, of the Firm of Wirth and Company, Patent
Solicitors, at Frankfort on the Main, in the Empire of Germany, for an
Invention of "IMPROVEMENTS IN APPARATUS USED IN COMBINATION WITH>
ACOUSTIC INSTRUMENTS." A communication from Adolph Rettig, Barrister,
of Saarbrücken, in the Empire of Germany.
PROVISIONAL SPECIFICATION left by the said Frank Wirth at the Office
of the Commissioners of Patents on the 6th May 1881.
FRANK WIRTH, of the Firm of Wirth and Company, Patent Solicitors, at
Frankfort on the Main, in the Empire of Germany. "IMPROVEMENTS IN APPARATUS
USED IN COMBINATION WITH ACOUSTIC INSTRUMENTS." A. communication from
Adolph Rettig, Barrister, of Saarbrücken, in the Empire of Germany.
The improvements relate more particularly to the apparatus for which Letters
Patent, dated 9 March 1880, and No. 1014, were secured, and consists in improved
holders and fasteners for holding fast in any desired position the head or mouth
of the sound pipe. Also in improved holders or attachments for fastening the
hearing apparatus on the head or shoulders, and in dispensing with the sound
board.
The improvements are performed by using metal or other band to pass on or
over the head and behind the ear. Said band carries a short pillar or support fitted
with a split ring with a screw adjustment for gripping and holding the sound
tube; the band may be covered with flowers or feathers, or otherwise concealed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frank Wirth in the Great Seal Patent Office on the 1st November.
1881.
FRANK WIRTH, of the Firm of Wirth and Company, Patent Solicitors, at
Frankfort on the Main, in the Empire of Germany. "IMPROVEMENTS IN APPARATUS
USED IN COMBINATION WITH ACOUSTIC INSTRUMENTS." A communication from
Adolph Rettig, Barrister; of Saarbrücken, in the Empire of Germany.
This Invention consists chiefly in improvements in the apparatus for which I
have obtained the Letters Patent, No. 1014, of the year 1880. The first part of
this Invention consists in an appliance for holding the head or terminal of the
sound pipe in the desired position. It is illustrated by the accompanying
Drawings, in which Figure 1 shows a plan of the whole appliance, while Figures 2,
3, & 4 are detail views. Two springs A & A partly enclosing the head, and
capable of being slided over each other at the top reach downward behind the right
and left ear, each carrying at its lower end (a, a¹,) a short post (B, B',) which ends
in a small head (b, b¹). The latter is perforated for the reception of a pin C and
provided with a set screw D. The front end of the said pin, situated towards the
opening' of the ear, is provided with a ring (c, c,) having a diameter equal to the
diameter of the sound pipe for which the holding apparatus is intended. The end
of the sound pipe is passed through this ring, subsequently provided with its head
or terminal, and the latter placed in the required position in or at the outer opening
of the ear by turning the pin (B, B',) or sliding the same in its bearing b. The
pin (B, B',) with its ring and the head of the sound-pipe are then fixed by means
of the 'set-screw D. This apparatus has the advantage that the head or terminal
of the sound-pipe is firmly held in any desired position, and that the apparatus is
fixed independently of the external ear. Moreover, this apparatus may be applied
to any sound pipe, not only to the acoustic apparatus described by the Specification
of the said Letters Patent.
The above described apparatus may also be used for fastening small light acoustic
instruments to the head. For this purpose a second little post or support, similar
in shape to the first, is adjusted on the flat spring over or under the support B, B,
(in this latter case the spring being lengthened and at a suitable distance from the
latter), or this additional support may be attached to a band secured to the spring.
The head of this second support is perforated from top to bottom and the shank
of the articulated appliance of the sound-pipe passed through its opening. The
sound-pipe is connected with the ear in the usual manner by adjusting a short
connecting pipe on the end of the sound-pipe, the end of the short pipe passing
through the ring c, c, into the outer ear. If using this apparatus all noises
resulting from movements of the body, dress, and sound-pipe are dispensed with.
Apparatus of moderate size may be adjusted on the shoulders by applying a bearing
plate (like a shoulder-piece or epaulet), provided in the middle with a short hollow
post or shank which may be turned up or down. The shank of the articulating
apparatus is introduced into this holder or hollow post, and the adjustment made
as described.
The inventor has discovered by experiments that it is sufficient to introduce into
the sound-pipe in the ear or near the latter a short sonorous tube, whose tone and
power of vibration must be very, different from that of the sound-pipe for entirely
dispensing with the troublesome resonance produced by other hearing apparatus.
The reduction of the strength of the tone is lessened by choosing well conducting
tubes. The short tube used for avoiding resonance may be of wood, glass, &c.,
and should have a high tone. The mouth-piece of the sound-pipe itself may be in
this way adapted for.avoiding resonance.

page_text: Or a short intermediate pipe of wood or glass, &c., may be inserted in the sound-
pipe near the ear for avoiding resonance, said intermediate pipe being introduced
with one end into the sound-pipe, while its other end is stuck into a short india-
rubber-pipe to be introduced into the outer ear. This intermediate pipe may, if
suitable, be inserted at the other end of the sound-pipe, or such intermediate pipes
may be inserted at both ends of the sound-pipe. The length of the intermediate
pipe (especially of its free uncovered part) determines the degree in which the
sound is lessened and resonance dispensed with.
This efficient means for dispensing with the resonance of acoustic apparatus may
be used for other sorts of acoustic apparatus. The use of glass-tubes of one inch
length is recommended as very suitable for avoiding resonance without considerably
lessening the sound.
FRANK WIRTH. (L.S.)