IMPROVEMENTS IN APPARATUS BY MEANS OF WHICH SCULPTURE AND OTHER SOLID OBJECTS MAY BE COPIED, ENLARGED, AND REDUCED
Year: 1879

page_text: LETTERS PATENT to William Chase Prescott and George Simonds, both of
Buckingham Palace Road, in the County of Middlesex, for the Invention of
"IMPROVEMENTS IN APPARATUS BY MEANS OF WHICH SCULPTURE AND OTHER
SOLID OBJECTS MAY BE COPIED, ENLARGED, AND REDUCED."
Sealed the 1st July 1879, and dated the 4th January 1879.
PROVISIONAL SPECIFICATION left by the said William Chase Prescott and
George Simonds at the Office of the Commissioners of Patents on the 4th
January 1879.
WILLIAM CHASE PRESCOTT and GEORGE SIMONDS, both of Buckingham Palace
Road, in the County of Middlesex. "IMPROVEMENTS IN APPARATUS BY MEANS OF
WHICH SCULPTURE AND OTHER SOLID OBJECTS MAY BE COPIED, ENLARGED, AND
REDUCED."
The improvements consist of a bed plate furnished with two or more revolver
tables working on axles and supports thereon, and connected by a metal band or
otherwise in such manner that the exact amount of horizontal movement of either
table is imparted to the other, these tables being intended to support the work or
works to be copied, enlarged, or reduced.
At or near one end of said bed plate is placed a standard capable of adjustment
both vertically and horizontally as desired, and furnished with a gimbal bearing
carrying a long bar or carrier, which is furnished with two or more adjustable
pointers, capable of being slided and adjusted on the said bar to a scale which may
be marked on it. Said bar is also furnished with pulleys, one or more with counter
weights for supporting the bar in horizontal equilibrium or otherwise by means of
attachments fixed in the ceiling or in other convenient place or structure. The
pointers are so constructed as to have a joint parallel movement when desired.
All the parts may be of metal or of metal and wood combined.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Chase Prescott and George Simonds in the Great Seal Patent
Office on the 3rd July 1879.
WILLIAM CHASE PRESCOTT and GEORGE SIMONDS, both of Buckingham Palace
Road, in the County of Middlesex. "IMPROVEMENTS IN APPARATUS BY MEANS OF
WHICH SCULPTURE AND OTHER SOLID OBJECTS MAY BE COPIED, ENLARGED, AND
REDUCED."
The object of our Invention, which we call the iconograph, is to enable the
operator therewith to define from given models according to any mathematical scale,
either of equality, of increase, or of diminution, the forms and relative dimensions of
solid bodies. The Invention consists of certain machinery or apparatus composing
the above instrument, which is made and used as follows, reference being had to
the Drawings hereto annexed, in which Figure 1 is a side view; Figure 2, plan;
Figure 3, section at Z, Z; and Figure 4, section at X, X. Two tables (A), (A), or
other means of support, each capable of movement around its own axis in a plane
common to or parallel with that of the other. An inflexible bar, tube, or girder of
any shape or material, which we call the radial arm (B) moving around a fixed
point in its fulcrum (a) which lies in its longitudinal axis of construction. This
motion is effected by the aid of a joint, hinge, socket, gimball, or other equivalent
mears of motion and support (b) located at or about said centre of motion. The
said radial arin possesses also the quality of partial or complete revolution around
its said longitudinal axis. Two or more pointers (C), (C), each consisting of a
carrier (c) and a point (d), the former working on the radial arm in such a manner
that the axes of motion of the pointers are parallel, and intersect the axis of the
radial arm at right angles. The said pointers possess a circular movement on their
own axis of motion, and may be constructed with the capacity for being lengthened
or shortened according to the requirements of the scale adopted. They are so
coupled together as to ensure perfectly equal angular movement, which is accom-
plished by means of a rod (e) or rods, or by any of the methods of coupling pre-
scribed for the tables. As many pointers are provided as there are tables in use,
one pointer being opposite to and working above and in connection with each
table. The centres of motion of the tables (A) and of the radial arm at its fulcrum
(a) all lie in the same vertical plane, and the rotary movement of the tables must
be for working purposes through the same number of degrees on the arcs of circles
struck from their centres of motion. The movements of the tables may be inde-
pendent, in which case such movements will be measured from fixed points, or on
a vernier scale, or they may be simultaneous and automatic, in which case the
uniformity in angular velocity is obtained by the use of a belt, chain, cord, wire,
or ribband of steel (f) or other metal, or by means of gearing, friction wheels, or
endless screws working on worm wheels or on racks. That portion of the pointers
(C) called the points (d) may be either straight, curved, or angular in shape,
according to the requirements of the work, and of any convenient length, subject
to the condition that their respective lengths measured from the respective centres
of motion of their carriers shall bo to each other as are the distances of the re-
spective centres of motion of the carriers from the centre of motion or fulcrum (a)
of the radial arm (B). The distances from the centre of motion or fulcrum (a) of
the radial arm to the centres of motion of the several pointers (C) must be the
same as are the distances from the same centre of motion or fulcrum (a) to per-
pendiculars projected above the centres of the respective tables opposite to and
belonging to such pointers respectively. For the purpose of fixing the radial
arm (B) at any given angle of elevation or depression, and of raising and depressing
it through short distances while the work at or near a special point is in progress
a compound pulley or system of pulloys may be employed, with or without a micro-
meter attached to and connecting the radial arm (B), with a fixed point (h) above

page_text: the fulcrum (a), the counterpoise being a weight attached to the cord after the
latter has passed over the last upper pulley, and a break or stop may be placed
upon the lower pulley of the system, or a counterweight may be attached to a pro-
longation of the radial arm beyond the fulcrum, or a movable are may be employed,
connecting the radial arın and the column, supporting its fulcrum with a worm
wheel or break or other well known means of arresting motion. The distances
between perpendicular lines projected from the contres of motion of the tables and
of the radial arm determine the relative proportions between the given model and
the required replica. When it is required to produce an exact copy without
enlargement or diminution the tables with their supports, connections, or means for
producing and regulating their motions remain as stated. The radial arm has its
general line of direction vertical instead of horizontal. Its fulcrum or contre of
motion is in a plane vertical to or parallel with the plane in which lie the tables
and their centres. The pointers work on an inflexible cross-bar, which is at right
angles with the radial arm, and at the same time parallel to the common vertical
plane or planes, in which are the centres of motion of the tables and the radial arm.
This cross bar is firmly held by a sliding frame, which frame is capable of motion
upwards or downwards on the radial arm, and of being fixed at any given point.
The cross bar has one motion only, videlicet, a circular or revolving motion around
its own axis within the grasp of its supporting framework. The attachment con-
nection and action of the pointers are the same as above described, except that in
this case they are of equal length, and their points when moved describo equal
and similar ares. The radial arm has but one motion on its fulcrum, videlicet, in a
plane perpendicular to and at right angles with the common plane or planes in
which lie the centres of the table and its own fulcrum or contre of motion. When
in use it is made to approach or recede from the work in progress on the tables,
and is when required held in place either by guides, along which it works, and to
which checks are attached for determining its stops, or by pulleys working in its
plane of motion, or so adjusted as to cause it to move and remain therein. Having
described the nature of our Invention we claim, the combination of two or more
revolving tables with an inflexible rod or radial arm supporting movable pointers,
or an inflexible cross bar, substantially as described, and for the purposes named.
Also, the combination of the inflexible cross bar with the radial arm for supporting
the pointers, substantially as described, for the purposes nained. Also, the com-
bination of two or more pointers working on a radial arm or on a cross bar moving
on such radial arm, and operating above and in connection with two or more re-
volving tables, substantially as described, for the purposes named. Also, the steel
belting or ribband, operating to produce automatic motion in the tables, sub-
stantially as described, for the purposes named.
In witness whereof, we, the said William Chase Prescott and George Simonds,
have hereunto set our hands and seals, this Third day of July, A.D.
WILLIAM CHASE PRESCOTT. (Ls.)
GEORGE SIMONDS.
(L.S.)