IMPROVEMENTS IN PANTAGRAPHS APPLICABLE TO DRAWING PURPOSES, AND TO SKETCHING FROM NATURE
Year: 1878

page_text: LETTERS PATENT to William Francis Humphries, of Limerick, in the County
of Limerick, Ireland, for the Invention of "IMPROVEMENTS IN PANTAGRAPHS
APPLICABLE TO DRAWING PURPOSES, AND TO SKETCHING FROM NATURE," A
communication from abroad by James Thom, of Carrollton, Louisiana, in the
United States of America.
Sealed the 21st January 1879, and dated the 24th July 1878.
PROVISIONAL SPECIFICATION left by the said William Francis Humphries
at the Office of the Commissioners of Patents on the 24th July 1878.
WILLIAM FRANCIS HUMPHRIES, of Limerick, in the County of Limerick, Ireland.
"IMPROVEMENTS IN PANTAGRAPHS APPLICABLE TO DRAWING PURPOSES, AND TO
SKETCHING FROM NATURE." (A communication from abroad by James Thom, of
Carrollton, Louisiana, in the United States of America.)
This Invention relates more particularly to an instrument for copying drawings,
usually denominated "pantagraph," and consisting of four bars jointed together
and provided with a marking and tracing point, by means of which designs are
readily drawn to any required size, either enlarged or reduced, with perfect
accuracy.
The Invention consists,-
First. In the peculiar construction of the points, so as to render them inter-
changeable.
Second. In providing the instrument with a "sight" for sketching landscapes and
other subjects from nature.
Third. In providing the drawing board with a fixed sight for facilitating the
sketching from nature.
The marking point and tracing point are each provided with a base flange, having
an open slot, through which passes a fastening screw, by which the points are secured
to their respective bars.

page_text: On the under side of the base flange a projection or stud is formed, which engages
in a corresponding depression or cavity formed in the under side of the respective
bar, so that by placing the projection or stud in the said depression or cavity of the
bar and applying the screw through the slotted flange, the point is readily and
accurately secured in place on the respective bar.
Upon loosing the said screws the points are readily detached from the bars and
interchanged.
For sketching landscapes, buildings, and other objects from nature, I apply the
instrument to a drawing board in such a manner that one bar will project above the
board, and to this bar I fix a sight, consisting of a needle point suitably arranged in
a vertical position, in order that the picture may be drawn on the board by the
marking point, by following the outlines of the object with the said sight, care being
taken to keep the eye always in the same position.
I
In order to prevent the eye point from being shifted as the drawing progresses,
provide a stationary sight, composed of a wire of suitable length, terminating in a
point and provided with a flange at its base, by which it is attached to the upper
edge of the drawing board in such a manner that it will be arranged at a short
distance in front of the eye of the operator.
By bringing the eye opposite to this stationary or fixed sight and the moveable
sight (that attached to the bar of the instrument), in line with the object to be
drawn, an accurate perspective view of any object can be produced in a very short
time, as the said stationary or fixed sight enables the operator to maintain the eye
stationary while following the movements of the sight affixed to the instrument.
For sketching objects in close proximity to the operator, such, for instance, as
the profile of a person, the sight attached to the instrument may be replaced by
a wire of suitable length, which is brought in contact with the object to be drawn
and passed along the outlines thereof.
For the purpose of retaining the pantagraph in an elevated position away from
the drawing board, I use a brace or guy line, one end of which is attached to an
upright bar secured to the base of the instrument, and the other end attached to
the extreme end of the bar, which springs from said base.

page_text: This Invention relates more particularly to an instrument for copying drawings,
usually denominated "pantograph," and consisting of four bars jointed together
and provided with a marking and tracing point, by means of which designs are
readily drawn to any required size, either enlarged or reduced, with perfect
accuracy.
The Invention consists,-
First. Of the peculiar construction of the points so as to render them inter-
changeable.
Second. In providing the instrument with a "sight" for sketching landscapes
and other objects from nature.
Third. In providing the drawing board with a fixed sight for facilitating the
sketching from nature.
The marking point and tracing point are each provided with a base flange, having
an open slot, through which passes a fastening screw, by which the points are secured
to their respective bars.
On the under side of the base flange a projection or stud is formed, which projec-
tion or stud engages in a corresponding depression or cavity formed on the under
side of the respective bar, so that by placing the projection or stud in the said
depression or cavity of the bar, and applying the screw through the slotted flange,
the point is readily and accurately secured in place on the respective bar.
Upon loosening the screws the points are readily detached from the bars and
interchanged.
For sketching landscapes, buildings, and other objects from nature, I apply the
instrument to a drawing board in such a manner that the one bar will project above
the board, and to this bar I apply a sight, consisting of a needle point suitably
arranged in a vertical position, in order that the picture may be drawn on the board
by the marking point by following the outlines of the object with the said sight,
care being taken to keep the eye always in the same position.
In order to prevent the eye point from being shifted as the drawing progresses, I'
provide a stationary sight, which is composed of a wire of suitable length, termi-
nating in a point and provided with a flange at its base, by which it is attached to
the upper edge of the drawing board in such a manner that it will be arrangod at a
short distance in front of the eye of the operator.
By bringing the eye opposite to this stationary or fixed sight, and the movable
sight (that is attached to the bar of the instrument) in line with the object to be
drawn, an accurate perspective view of any object can be produced in a very short
time, as the said stationary or fixed sight enables the operator to maintain the eye
stationary while following the movements of the sight attached to the pantograph.
In sketching objects in close proximity to the operator, such, for instance, as the
profile of a person, the sight attached to the instrument may be replaced by a wire
of suitable length, which is brought in contact with the object to be drawn and
passed along the outlines thereof.
For the purpose of retaining the pantograph in an elevated position away from
the drawing board, I use a brace or guy line, one end of which is attached to an
upright bar secured to the base of the instrument, and the other end attached to the
extreme end of the bar, which springs from said base.

page_text: In order that my said improvements may be more readily understood, I will
describe the accompanying Sheet of Drawings, viz. :-
Fig. 1 is a view of the pantograph applied to a drawing board for sketching a
landscape from nature.
Figs. 2, 3, and 4 are fragmentary bottom views of the ends of the bars of the
pantographs, with the points applied thereto.
Fig. 5 shows the slotted flange above referred to.
Fig. 6 represents a fragmentary sectional view of the marking point secured to
one of bars.
Fig. 7 is a side view of the fixed sight secured to the drawing board.
Like letters of reference designate like parts in each of the Figures.
A, A1, A2, A³, represent the four bars of the pantograph joined together in an
ordinary manner; B represents the base to which the stationary end of the instru-
ment is pivoted, and which is secured to the drawing board by a thumbscrew b', or
in any other suitable manner; C is a brace or guy line secured in the manner
herein-before described for retaining the instrument in an elevated position over
the drawing board; D is the tracing point; and E, the marking point; f; the base
flange, having an open slot f¹, through which passes the screw g, by which the
points are secured to their respective bars; h is a projection formed on the under
side of the base flange (Fig. 6), and engaging in the corresponding depression or
cavity formed in the under side of the respective bar.
When the dsign to be copied is to be enlarged the marking point E is secured to
the outer bar A³, and the tracing point D to the bar A¹, while when the design is to
be reduced in size the arrangement of the points is reversed.
Upon loosening the screw g the points are readily detached from the bars and
interchanged; i is a projecting sight, consisting of a needle point secured to the end
of the bar A³, for sketching landscapes, buildings, and other objects from nature.
The action of the instrument in sketching from nature is illustrated in Fig. 1,
with the bar As projecting above the drawing board and the marking point secured
to the bar A².
'
The outlines of the picture are drawn by following the outlines of the object
with the sight i, care being taken to keep the eye always in the same position.
K is a stationary sight, terminating in a point and provided with a flange K', by
which it is attached to the drawing board in the manner and for the purpose herein-
before described.
Having thus described the nature of the said Invention, and the manner in which
the same may be used, I would observe that what I claim as the Invention secured
to me by the herein-before in part recited Letters Patent is,-
1. The points D and E, each provided with a slotted base flange f and projection h,
in the manner substantially as herein described and set forth.
2. The combination with a pantograph of a projecting sight i, attached to the
outer bar A3, for sketching from nature, substantially as set forth.
3. The combination with a pantograph, provided with a sight i of a drawing
board, having a fixed sight K, substantially as and for the purpose specified.
In witness whereof, I, the said William Francis Humphries, have hereunto set 4
iny hand and seal, this Eighteenth day of January, in the year of our Lord
One thousand eight hundred and seventy-nine.
WILLIAM FRANCIS HUMPHRIES. (L.S.)