Year: 1889

page_text: Date of Application, 12th Mar., 1889
Specification Accepted. 11th May, 1889
I, GEORGE DIXON, White House, Great Ayton, Yorkshire, Surveyor do bereby
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:
(a.) A sheet or plate A shewn in Figs. 1, 7 and 8 and in part in Figs. 3, 4, 5, 6 and 9,
or a series of sheets or plates which I term Arcigraphs and Paracentrographs of what-
ever shape size designation or material for the purpose of describing or drawing.
curves in which, any number of convex curves B. and concave curves C. or either or
both whether derived from Circles, Helices, Parabolas, Hyperbolas or Ellipses, of
various radii or axes, or any amplification or modification thereof, or any other variety
or form of curve, arranged at any convenient distances from each other in the same
sheet or plate or series of sheets or plates, the principle whereof is shown on the
accompanying drawings numbered respectively 1, 2, 3, 4, 5, 6 and 7.
(b.) A line D. on any such sheet or plate or series of sheets or plates giving the line
of radius of all given arcs whether convex or concave.
(c.) A moveable reversible plate or bar E. Fig. 2 which 1 term a Radigraph of
whatever shape, size, designation or material having guides F. to run either in
cavities G. between two curves or against the outer or inner edge of any circle or
curve for the purpose of producing erecting determining or describing by means of
the straight-edge H. perpendiculars and radii to convex and concave curves or both or
either of them and for use with protractors for plotting or subtending angles.
The whole or any part of the aforesaid improvements or the principles embodied or
implied therein, on the Drawings, or in the claims following, are applicable to all
branches of engineering, architectural, technical or other drawing.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what I
claim is
1. The words, names, terms or styles of Arcigraph, Paracentrograph and
Radigraph.
2. The principle of arranging convex and concave curves in cavities in the same
sheet or plate.

page_text: 3. The principle of having convex and concave curves of the same radius or axis
arranged in the same cavity.
4. The principle of having convex and concave curves of different radii or axes
arranged in the same cavity.
5. The principle of arranging any number of curves in cavities in the same sheet or
plate having one common centre.
6. The principle of arranging any number of curves in cavities in the same sheet or
plate with different centres.
7. The principle of arranging any number of curves in cavities in the same sheet or
plate with one common central line of radius.
8. The principle of arranging any number of curves in cavities in the same sheet or
plate with different lines of radii.
9. The principle of shewing by means of a line or mark on the sheet or plate the
line of radius and perpendicular to both convex and concave curves or either of them.
10. The principle of producing, erecting, determining or describing perpendiculars
or radii or plotting or subtending angles by means of the straight edge of a moveable
plate or bar having guides to run in cavities between circles or curves or against the
outer or inner edges of circles or curves.
11. The principle of having such bar reversible.
12. The principle of having the straightedge of such bar or plate actually inter-
secting or crossing the line of the circle or curve in producing, erecting determining
or describing perpendiculars or radii.
13. The principle of using such bar or plate with either convex or concave curves or
both in the same cavity without removal."
Dated this Eleventh day of March 1889.