An Improved Device for Use in Teaching and Testing Model and Perspective Drawing.
Year: 1899

page_text: Date of Application, 21st July, 1899-Accepted, 26th Aug., 1899
COMPLETE SPECIFICATION.
An Improved Device for Use in Teaching and Testing Model and
Perspective Drawing.
We, THOMAS WRIGHT PERRY, of No. 2, Blackford Road, Sparkhill, in the
County of Worcester, Government Certificated School Master, and WILLIAM
GEORGE TYE, of Lynmouth, Dora Road, Small Heath, in the County of Warwick,
Government Certificated School Master, do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement: -
This invention relates as hereinafter described to an improved device for use
in teaching and testing model and perspective drawing and also for testing
angles proportionally and obtaining the vanishing points of the parallel lines.
In order that our invention may be clearly understood we will describe it by
reference to the accompanying drawings the same letters of reference indicating
similar parts throughout.
Figures 1 and 2 show in front and end elevation respectively our improved
device.
Figure 3 is a section of the same Figure is a back elevation, and Figure 5
is a front elevation showing the position of the parts when the device is in use,
Figures 6 and 7, being detail parts. A represents a frame shown separately at
Figure 6 made of metal celluloid or other suitable material furnished with the
aperture and having the rounded sides e, e, and the turned up edges B, B
forming guides into which fits a vertical slide C made of the same material.
D and D are two slides sliding laterally in the guides E, E. Fis a central
division piece perpendicular to the bottom of the aperture a of the frame A. G
is a pointer made of wire connected to the base of the centre piece F by a thumb
screw or by other suitable means. G2 is a similar pointer connected in like
manner to the projection f. The device is used in the following manner:
The pupil holds the device at arms-length and views the object to be drawn
through the aperture a. Suppose this to be a cube. The base of the centre
piece is held to cover the nearest bottom corner: the width of the faces is obtained
by adjusting the sides D, and D2. The height is read off by the numbered divi-
sions on the plates D, D2 and by the top portion of the plate A. The width is
read off by the numbered divisions on the bottom of the aperture a. Thus the
height of the verticals and relative width of the faces are obtained. The receding
edges are fixed by adjusting the upper pointer G and the lower pointer G.
In this way the angles are determined. When all the parts are in position the
device is placed by the side of the drawing and will indicate if the drawing be
correct.
In Figure 5 we show the different positions in which the slides may take when
adjusted.
It is apparent that the device may be adapted to test the accuracy of any geo-
metrical figure

page_text: Having now particularly described and ascertained the nature of our invention
and in what manner the same is to be performed we declare that what we
claim is :-
1. The combination of a device for teaching and testing model and perspective
drawing consisting of the frame A provided with the aperture a vertical slides C,
the lateral slides D, D2, division piece F, and pointers G and G2, all co-operating
together substantially as in the manner described and for the purpose set forth.
2. The improved device for teaching and testing the accuracy of model and
perspective drawing substantially as described and illustrated in the various
figures of the drawing and for the purpose set forth.
Dated this 17th day of July 1899.
WILLIAM HENRY BARACLOUGH,
36, Temple Street, Birmingham, Agent for the Applicants.