IMPROVEMENTS IN ORGANS HARMONIUMS AND LIKE REED INSTRUMENTS
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by James Baillie Hamilton at the
Office of the Commissioners of Patents on the 25th May 1882.
JAMES BAILLIE HAMILTON of Studland Street Hammersmith in the County
of Middlesex "IMPROVEMENTS IN ORGANS HARMONIUMS AND LIKE REED
INSTRUMENTS
"
In securing purity of tone from a reed the general object is to preserve as far as
possible the continuity of the current of air which passes through it.
It has been previously endeavoured to effect this by reducing the amptitude of
the vibration of the reed-tongues and for this purpose strings rods or rings have
been employed attached to some point external to the reed tongue whose motion is
restricted.
By this means the motion of the reed tongue was restricted or constrained and
the tone proportionately purified. But the reed tongue having to overcome the
additional resistance thus offered to it was unable to speak or depart from its
position of rest with sufficient promptitude for musical requirements.
By my present Invention I impose a constrain upon reed tongues which
accumulate rapidly as they leave their position of rest; and moreover is at its
minimum when the tongues are required to be set in motion.-thus the conditions
necessary for promptness of speech and also for purity of tone are both complied
with.
My Invention consists of a compound oscillating reed so constructed that it is
partially fixed at both ends and partially free at both ends. The free ends
controlling each other through the medium of that portion of the compound
reed which connects them and on which they are capable of being oscillated.
As an example I take a reed-frame of suitable width and instead of a reed-
tongue free at one end I set over the orifice a reed-tongue or thin plate fixed at
both ends forming a band or reed fixed at both ends and tending to vibrate in its
central portion if left in this condition. Instead of leaving it thus however I cut
through the root of each end of the reed on opposite sides as far as the centre at
right angles to the reeds-length and then pursue the cut in both cases longitudinally
down the centre of the reed until I approach the middle portion between the two
ends of the compound reed thus formed. The compound reed has now two fixed

page_text: The free
extremities and also two free extremities opposed to each other.
extremities being capable of oscillating on that portion of the compound reed which
connects them, and the elasticity of this portion may be diminished or increased at
will by thickening or reducing its substance.
Instead of forming this compound reed tongue out of the substance of one plate
I take two reed tongues and place them over a common orifice and unite them by
a piece of metal instead of by their own substance.
Instead of thus uniting reed-tongues over a common orifice I take two separate
reed-tongues with their own frames and unite the frames so as to bring their
tongues into the position above described their free extremities now oscillate
through the piece of metal which connects them. If this piece of metal be rigid
the constraint which the reed tongues exercise upon each other is so great as to
raise them an octave above their original pitch at the same time their freedom is not
impaired owing to the assistance they afford to each other in recovery from the
dip" caused by the wind pressure.
The strip of wire instead extending rigidly from tongue to tongue may be
lengthened into a spring or coil in its intervening portion whereby this interval of
pitch may be reduced.
I have termed this reed an oscillating reed because such is its motion if displaced
when not under the action of wind. But under the action of wind this tendency
to oscillate becomes a source of mutual constraint whereby the results above
described are effected.
The levers of the pallets convering the openings by which the wind is admitted
to the reed may be arranged alternately with their pallets and their centres
reversely placed so as to give a very advantageous increase of width for the wind
passage. To operate the levers there is provided a rail or bar carrying squares or
bell crank levers one for cach lever. These squares or bell crank levers are each
centred at their middle to the bar and at their one end are moved from the key
board through ordinary or other suitable mechanism rods or levers. The other
end of each square or bell crank lever is bent into or formed with a sideway
projecting piece for bearing upon and operating its lever hereinbefore described the
componnd reeds are preferably "mounted" on a hollow block or reed-chamber
preliminary to the reed-chamber or channel which reinforces the note. so that I am
enabled to enlarge or constrict the orifice which connects them and so regulate
the passage of the wind.
I leave a strip of metal or leather or suitable substance between the surfaces in
contact of these two channels and having a hole which can be enlarged by cutting
or altered by shifting its relation in regard to the orifices connecting the two
chambers.