AN IMPROVEMENT IN THE CONSTRUCTION OF A PEDAL HARP
Year: 1813

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, J, JACOB
ERAT, of Wardour Street, in the Parish of Saint James, Westminster, in the
County of Middlesex, Harpmaker, send greeting.
WHEREAS His most Excellent Majesty King George the Third, by. His
Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Eighth day of May,
in the fifty-third year of His reign, for Himself, His heirs and successors,' did
give and grant unto me, the said Jacob Erat, my executors, administrators,
and assigns, His especial licence, full power, sole privilege and authority,
that I, the said Jacob Erat, my exécutors, administrators, and assigns, by
myself and themselves, or by my and their deputy or deputies, servants or
agents, or such others as I, the said Jacob Erat, 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 of years therein expressed,' should
and lawfully might make, use, exercise, and vend, within England, Wales,
and the Town of Berwick-upon-Tweed, my Invention of "AN IMPROVEMENT
IN THE CONSTRUCTION OF A PEDAL HARP;" in which said Letters Patent there
is contained a proviso, obliging me, the said Jacob Erat, by an instrument
in writing under my hand and seal, particularly to describe and ascertain the
nature of my said Invention, and in what manner the same is to be performed,
and to cause the same to be inrolled in His said Majesty's High Court of
Chancery within two calendar months next and immediately after the date of
the said Letters Patent, as in and by the said Letters Patent, reference being
thereto had, will more fully appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Jacob Erat, do hereby declare that the nature of my said Invention, and
manner in which the same is to be performed, are particularly described and
ascertained in manner following, that is to say:-
In the Drawings or sketches hereunto annexed, Fig. 1 represents part of an
harp and more particularly of the arm or upper curved part to which the
strings are fastened, and in which the machinery for tuning and stopping the
same is usually fixed or put. A shews the tuning pin of one of the strings
A, L; B is the adjustable bridge pin, and C is a fork, which by being turned on
its axis, when requisite, by means of machinery of cranks or tumblers, con-
necting pieces and a pedal, is caused to embrace or confine the string, and
form the sharp note next above the tone of the open string, at the same
time that all the other strings of the same denomination at N, N, N, &c. are
affected in the like manner by their respective forks, and the said tuning
pin, bridge pin, forks, machinery, and pedal are already in common use in
harps, and are not exclusively claimed by me, but I have inserted the same
in my said Drawings or sketches, in order to shew the manner in which the
same may or are to be used along with my said Invention.
J, K, Fig. 1, represents a new stop, applied and worked below the fork C,
and shewn seperately in Fig. 2, in which last Figure the red parts denote the
interior machinery, nearly of the same kind as is used to work the forks, but
quite separate and apart from that of the forks; the piece m, r, is moved by
the connecting bars p, q, and by the communications G, F, R, of Fig. 1, and
carries a lever or arm K, (Fig. 2,) which is made adjustable as to the effective
length thereof by a slit and screw, as shewn at the center pin of m, r, upon
which the said lever or arm is carried; m, n, represents a connecting bar
which moves the piece n, s, upon the center at S, and upon the same center is
fixed the lever or arm I, adjustable as to the effective length thereof by similar.
means to those shewn at K. And upon the extremities I and K of the levers
aforesaid (Fig. 1) are fixed upright pins or studs, which are pressed against
the string (and the like against all the other strings of the same denomination),
whenever the pedal connected with G, and thence with F, R, K, P, P, &c.
Fig. 1, is duly pressed down, and by that means the said strings are made to
afford the whole note or notes next above the note or notes afforded by the
said string or strings when open. And whereas the truth and accuracy of the
balf note, afforded by the fork C in common harps, are produced and deter-
mined by means of the adjustment of the bridge pin B, but the same truth
and accuracy of the stopped whole note could no., be had by a second fork
upon each string, particularly in the event of any change of figure in the belly

page_text: of the instrument: Now, I do produce a like and equally perfect adjustment
for the said stopped whole note by my adjustment of the lever or arm K, and
do also by the adjustment of the lever or arm keep the counter pressure at such
distance, as upon trial may be found to be most firm in the production of a
clear and good tone, and I do further declare, that I do work the range of
forks by one pedal F, Fig. 3, for each series of notes of the same name, and
the correspondent range of levers and pins for the same series of notes by
another pedal A, so that the said pedals do act separately and distinctly from
each other upon the respective levers of communication J, E, and D, G, and
upon the respective forks, or arms, or levers connected therewith. (See the
ground plan of the same apparatus in Fig. 4, where the same parts are denoted
by the same letters of the alphabet.) Or otherwise, in case it should be desired
to move the forks for the half note, and subsequently the arms or levers for
the other half note, making in the whole one entire note or tone, and that the
same be done by one pedal, I do then make and use the apparatus, shewn in
Fig 5, 6, and 7, in all which Figures the same letters denote the same things.
fis the pedal connected by the bars e, g, with a tumbling piece or double
camb, moveable on the center W; the two levers h, E, (which is drawn in red),
and m, G, (which is drawn in black,) do respectively act at E and G in Fig. 1,
and do severally bear upon the acting faces of the double canib of the same
colours respectively as those of the levers; that is to say, the camb c, d, has its
face c rising or receding from the center, and its face d circular, so that when the
pedal is pressed from p to 4, the red lever is raised by its camb, as shewn in
Fig. 6, and acts upon the range of forks, and when the pedal is farther pressed
from q to r, as in Fig. 7, the black lever is raised by its camb b, a, which has
its face b circular, and its face a rising or receding from the center, and thereby
acts upon the range of arms or levers, and during the first shift of the pedal
from p to g, the black lever is not moved, because the circular face b alone is
in contact with its extremity, and for the same or a like reason during the
second shift of the pedal from 2 to r, the red lever is not moved, because the
circular face d is then in contact with its extremity, and I do secure, or place,
or lodge the pedal in the positions at 9 and r by prominences, pins, or side
notches in the foot or frame work of the instrument, or by any of the well-
known mechanical means of securing pedals or levers in general in any per-
manent situation or position.
In witness whereof, I, the said Jacob Erat, have hereunto set my hand
and seal, this Third day of July, in the year of our Lord One thousand
……….1.1…………..und and thintoon.
JACOB ERAT. (L.S.)

page_text: AND. BE IT REMEMBERED, that on the same Third day of July, in the
year above mentioned, the aforesaid Jacob Erat came before our Lord the
King in. His. Chancery, and acknowledged, the; Specification aforesaid, and
all and every thing therein contained, in form above written: And also the
Specification aforesaid was stamped according to the tenor of the Statute in 5
that case made and provided.
Inrolled the same Third day of July; in the year' above written:.