IMPROVEMENTS IN PIANOFORTES
Year: 1872

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine,
Lake, & Co., Patent Agents, Southampton Buildings, London, for
the Invention of "IMPROVEMENTS IN PIANOFORTES."-A communica-
tion from abroad by Christian Frederick Theodor Steinway, of the
City and State of New York, United States of America, Manufac-
turer.
Sealed the 5th July 1872, and dated the 14th May 1872.
COMPLETE SPECIFICATION filed by the said William Robert Lake
at the Office of the Commissioners of Patents, with his Petition
and Declaration, on the 14th May 1872, pursuant to the 9th
Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL' COME, I, WILLIAM
ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London, send greeting.

page_text: executors, administrators, and assigns, Her Royal Letters Patent for the
same, and havo made solemn Declaration that it has been communicated
to me from abroad by Christian Frederick Theodor Steinway, of the
City and State of New York, United States of America, Manufacturer.
NOW KNOW YE, that I, the said William Robert Lake, do hereby
declare that the following Complete Specification, under my hand and
seal, fully describes and ascertains the nature of the said Invention, and
in what manner the same is to be performed, in and by the following
statement :-
This Invention consists in the arrangement in a pianoforte of a series
of strings in each of which the vibrations of that portion of the string
situated between the agraffe or its equivalent and the tuning pin are
brought in harmony with the vibrations of the main portion of the
string in such a manner that the purity and fulness of the tone of the
instrument is materially increased; also in the arrangement in, a
pianoforte of a series of strings in each of which the longitudinal
vibrations of that portion of the string situated between the sounding
board bridge and the hitch pin are brought in harmony with the
vibrations of the main section of the string so that the purity and
fulness of the tone of the instrument is improved.
In order to enable others to understand my Invention, I will hero
remark that the term "scale" of a pianoforte comprises the position of
the strings side by side or above cach other, their length, and thickness,
and their tension, and the said Invention is applicable to all stringed
instruments in which the sounds are produced by the action of
hammers.
こ
If the base tones of a stringed hammer instrument are sounded from
octave to octave towards the treble a great difference appears in the
effect of the various strings according to their length, as far as the
partial tones of the strings are concerned, which is due to the
spontaneous subdivisions of said strings in halves, quarters, eights,
sixteenths, and so on. The longest duration of the vibrations and the
highest quality to subdivide in partial tones is found in the strings
between the contra C and the small c. Within these limits each string
subdivides itself by the blow of the hammer, and by the transverse
vibrations due to the same in a large number of "nodes," whereby the
so called harmonic overtones are produced which render the funda-

page_text: mental tone rich and brilliant. At the same time this portion of the
strings particularly produces by the longitudinal vibrations a number of
unharmonic side tones making a whistling sound which disturbs the
purity of the tone. Both these qualities disappear as the height of the
¡ tones increases, so that the limit of a pure fundamental tone is found at
the a, while it is in most cases desirable to obtain a clear tone from c.
But the inherent firmness of the thick strings generally employed and
the great tension required on account of this thickness prevents the
string of the above-named c to make the proper transverse vibrations.
due to the fundamental tone, and a division into partial tones is out of
the question.
In order to effect or promote the subdivision of the string and to
produce the desired partial tones, I combine with that portion of the
string situated between the tuning pin a (see Drawing), and the main
agraffe 6 or the support which may serve the purpose of the said in
agraffe, a secondary agraffe c which supports the string and is placed at
a distance from the main agraffe corresponding to one of the above-
named subdivisions of the main section d of the string, that is to say, at
a distance equal to¼¼¼¼¼, or ¼ of the length of the main
section or to any combination of these fractions.
The main agraffe 6 which supports the string only at one point allows
the transverse vibration to extend to that part of the string between the
said agraffe and the tuning pin, the vibration of this part being in a
direction opposite to that of the main section of the string. By
inserting the second agraffe c at a distance from the main agraffe equal
to ½ ½ ½ ½ ½ or of the length of the main section of the
string, the subdivision of the string into partial vibrations and the
consequent production of harmonic overtones is effected or promoted,
and a clear strong and brilliant tone is obtained up to the highest note.
In the Drawing I have marked opposite to each tuning pin the
proportion existing between the distance of the two agraffes and the
length of the main section of the string.
By allowing the vibration of the string to extend bevond the main

page_text: absolutely cutting off the vibrations of the string at this point as
uniformly practised the cohesion of the metal is disturbed, and it is a fact
that nine-tenths of all the strings which break in a pianoforte do so from.
this cause under the action of the hammer. By adding my second period.
of vibrations the freedom of the motion of the string is promoted, and{
the danger that the same will break is materially decreased. The
unharmonic tones or the whistling sounds due to the longitudinal
vibration of the strings I avoid by supporting that portion of the string
between the bridge and the hitch pin at distances from the outer bridge
pins equal to ½ ½ ½ ½ ½ or of the length of the main portion 1
of each string or to any combination of these fractions.
16
By the sounding board bridge the continuation of the transverse
vibrations must necessarily be interrupted owing to the width of the
bridge supporting the string, whereby these vibrations are effectually
stopped. But particularly with strings of such great thickness as 1
generally used in pianofortes of recent construction, the longitudinal
vibrations of the strings extend in the metal itself to those portions
situated between the bridge and the hitch pins, and in order to avoid the
unharmonic tones due to these longitudinal vibrations I apply between
the bridge and the hitch ping under each string a support e at a
distance from the outer bridge pin corresponding to ½½½½ 1 1/
or of the length of the main section d of the string or to any com-
bination of these fractions.
"
16
In the Drawing I have marked opposite to each hitch pin tho
proportion existing between the distance from the support e to thos
bridge pin, and the length of the main section of the string. By these
means the unharmonic tones due to the longitudinal vibrations of the
strings are converted into harmonic tones, which being transmitted
through the bridge to the sounding board reach the car, and strengthen
and enrich the fundamental tone of the string instead of disturbing the
purity thereof as heretofore. The supports cand e may be made of
metal, ivory, or any other material capable of resisting the pressure of
the string.
Having thus fully described the said Invention as communicated to
me by my foreign correspondent, I claim,-
First. The arrangement in a pianoforte of a series of strings in cach
of which the vibrations of that portion situated between the agraffe or

page_text: its equivalent and tuning pin are brought in harmony with the
vibrations of the main section of the string substantially as described.
Second. The arrangement in a pianoforte of a series of strings in each
of which the longitudinal vibrations of that portion of the strings
situated between the extreme edge of the sounding board bridge and the
hitch pin are brought in harmony with the vibrations of the main
section of the string substantially as set forth.
In witness whereof, I, the said William Robert Lake, have hero-
unto set my hand and seal, this Fourteenth day of May, in
the year of our Lord One thousand eight hundred and seventy-
Witness,
CHAS. J. GoOOH.
W. ROB³. LAKE. (L.S.)