Scenographical Instrument by Christopher Wren
From Inventions
Name adopted by the inventor (in English scenographical instrument, from the Greek skéné=scene and graphein=to paint).
Contents |
Inventor
Christopher Wren (1632-1723)
Historic Period
ca. 1650
Description
Perspective instrument designed by Christopher Wren, mainly for surveying purposes: "A Scenographical Instrument, to survey at one Station" (Wren 1750). For this same function Wren also utilised a camera obscura: "A Perspective Box, to survey with it". The "scenographical" instrument consists of a vertical panel on which slides a rule carrying a sight and a pen. Through a system of wires and pulleys, the rule can easily be moved in any direction, keeping it always parallel to the base of the panel. The portion of the rule carrying the sight projects from the board to intercept the points sighted. The other part, with the pen, slides over the drawing paper to trace the positions of the points in perspective. The painter looks through a viewer, superimposes the sight at the end of the rule on the direction of the visual ray, and traces the corresponding position of the point sighted on the sheet of paper. The instrument's operation is similar to that of Christoph Scheiner's pantograph. A singular perspective instrument that combines Wren's invention with Scheiner's pantograph is found at the Museo Galileo di Firenze. It may have originated from the interest aroused by Wren's invention among the mathematicians of the Medicean court. Wren's instrument was in fact shown to Cosimo III de' Medici, during his visit to London in 1663, by Henry Oldenburg, who kept it in his collection of scientific instruments. Another variant was published in 1719 by Grellier de Serviere
Bibliographical Resources
Oldenburg, Henry. An instrument invented
diverse years ago by Dr. Christopher Wren, for deawing the Outlines of an
Object in Perspective, in "Philosophical Transactions of the Royal
Society", IV, 1669, pp. 898-899.
Grellier de Serviere. Recueil d'ouvrages curieuses de mathematique et de mecanique ou Description du cabinet de monsieur Grellier de Serviere, Lyon, 1719, p. 146, tav. 87, fig. 125.
Wren Jnr, Christopher. Parentalia: or, memoirs of the family of the
Wrens, London, 1750, pp. 198-199.
Bennett, Jim. The mathematical science of Christopher Wren , Cambridge,
Cambridge university press, 2002.
Images
 Nicholas Bion, Traitè de la construction et des principaux usage des instruments de mathèmatique, La Haye, 1723. |
Author of the entry: Filippo Camerota
