Centrolinead
Encyclopedia
The centrolinead was invented by Peter Nicholson
, a British
mathematician
and architect
, in 1814. It was used to construct 2-point perspective drawings
where one or both vanishing point
s existed outside the drawing board. Draftsmen
could use the instrument in pairs; one for each vanishing point on each side of the station point
.
Centrolineads were produced in various sizes. Typically a brass
fitting clamped the wooden
arms together. Fittings were produced in both right and left-handed configuration, and certain adjustable designs could be used on either side.
are placed near the edges of the drawing surface and serve as pivots for the arms. Pin placement is equidistant and symmetric across the horizontal line
. A third centrolinead could be used to construct 3-point perspective.
Peter Nicholson (architect)
Peter Nicholson was a Scottish architect, mathematician and engineer. Largely self-taught, he was apprenticed to a cabinet-maker but soon abandoned his trade in favour of teaching and writing...
, a British
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
mathematician
Mathematician
A mathematician is a person whose primary area of study is the field of mathematics. Mathematicians are concerned with quantity, structure, space, and change....
and architect
Architect
An architect is a person trained in the planning, design and oversight of the construction of buildings. To practice architecture means to offer or render services in connection with the design and construction of a building, or group of buildings and the space within the site surrounding the...
, in 1814. It was used to construct 2-point perspective drawings
Perspective (graphical)
Perspective in the graphic arts, such as drawing, is an approximate representation, on a flat surface , of an image as it is seen by the eye...
where one or both vanishing point
Vanishing point
A vanishing point is a point in a perspective drawing to which parallel lines not parallel to the image plane appear to converge. The number and placement of the vanishing points determines which perspective technique is being used...
s existed outside the drawing board. Draftsmen
Technical drawing
Technical drawing, also known as drafting or draughting, is the act and discipline of composing plans that visually communicate how something functions or has to be constructed.Drafting is the language of industry....
could use the instrument in pairs; one for each vanishing point on each side of the station point
Station point
A station point is a location or vantage point from which an artist or exhibitor intends an observer to experience an artwork.In photography, the station point is the location of the camera at the point in time when the camera records a view to a recording medium....
.
Centrolineads were produced in various sizes. Typically a brass
Brass
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin...
fitting clamped the wooden
Wood
Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...
arms together. Fittings were produced in both right and left-handed configuration, and certain adjustable designs could be used on either side.
Usage
Two short arms are set to form 90 degree angles against a third, longer drawing edge. PinsPin (device)
A pin is a device used for fastening objects or material together. It is usually made of steel, or on occasion copper or brass. It is formed by drawing out a thin wire, sharpening the tip, and adding a head. Nails are related, but are typically larger....
are placed near the edges of the drawing surface and serve as pivots for the arms. Pin placement is equidistant and symmetric across the horizontal line
Horizon
The horizon is the apparent line that separates earth from sky, the line that divides all visible directions into two categories: those that intersect the Earth's surface, and those that do not. At many locations, the true horizon is obscured by trees, buildings, mountains, etc., and the resulting...
. A third centrolinead could be used to construct 3-point perspective.