CHARLES BOURGEOIS (1759-1832), HIS ANTINEWTONIAN COLOUR THEORY AND THE RECONCILEMENT OF ART AND SCIENCE

Nuncius ◽  
2007 ◽  
Vol 22 (1) ◽  
pp. 15-48
Author(s):  
JOOST MERTENS
Keyword(s):  
White Light ◽  
Royal Academy ◽  
Three Dimensional ◽  
Colour Space ◽  
Art And Science ◽  
The Arts ◽  
General Rules ◽  
Colour Theory ◽  
Composite Nature ◽  
Academy Of Sciences

Abstracttitle ABSTRACT /title Between 1810 and 1825, Charles Bourgeois (1759-1832), miniaturist, pigment manufacturer and physicist, developed a colour optics that defied both the Newtonian view of the composite nature of white light and the widely accepted strict separation between science and the arts. In this paper four themes are discussed: the general rules of colour mixing and the resulting three-dimensional colour space CEI (Couleur, Excdent, Intensit); Bourgeois' theory of light as a vehicle for non-luminous colours; His attempt at disproving Newton's central principle of the unequal refrangibility of different colours; and his relation, or rather non-relation, with the Royal Academy of Sciences which considered Bourgeois' theory of light a piece of nonsense.

Opponent Center-Surround Contrast: Colour to Grey Conversion

2020 ◽  
Vol 2020 (1) ◽  
pp. 105-108
Author(s):  
Ali Alsam
Keyword(s):  
Evolutionary Algorithms ◽  
Three Dimensional ◽  
The State ◽  
Colour Space ◽  
Vision Science ◽  
State Of Art ◽  
Over Time

Vision is the science that informs us about the biological and evolutionary algorithms that our eyes, opticnerves and brains have chosen over time to see. This article is an attempt to solve the problem of colour to grey conversion, by borrowing ideas from vision science. We introduce an algorithm that measures contrast along the opponent colour directions and use the results to combine a three dimensional colour space into a grey. The results indicate that the proposed algorithm competes with the state of art algorithms.

scholarly journals IX. An account of trigonometrical operations in the years 1821, 1822 and 1823, for determining the difference of longitude between the Royal Observatories of Paris and Greenwich

1828 ◽  
Vol 118 ◽  
pp. 153-239 ◽  
Keyword(s):  
Royal Society ◽  
Royal Academy ◽  
The Difference ◽  
Academy Of Sciences ◽  
The Church ◽  
Royal Society Of London

In the year 1790, a series of trigonometrical operations was carried on by General Roy, in co-operation with Messrs. De Cassini, Mechain, and Legendre, for the purpose of connecting the meridians of Paris and Greenwich. In England, the work commenced with a base measured on Hounslow Heath, whence triangles were carried through Hanger Hill Tower and Severndroog Castle on Shooter’s Hill, to Fairlight Down, Folkstone Turnpike, and Dover Castle on the English coast; which last stations were connected with the church of Notre Dame at Calais, and with Blancnez and Montlambert upon the coast of France. An account of these operations will be found in the Philosophical Transactions for 1790. In the year 1821, the Royal Academy of Sciences and the Board of Longitude at Paris communicated to the Royal Society of London their desire, that the operations for connecting the meridians of Paris and Greenwich should be repeated jointly by both countries, and that commissioners should be nominated by the Royal Academy of Sciences and by the Royal Society of London for that purpose. This proposal having been readily acceded to, Messrs. Arago and Matthieu were chosen on the part of the Royal Academy of Sciences, and Lieut.-Colonel (then Captain) Colby and myself were appointed by the Royal Society to co-operate with them.

Funding and Directing Research or Rewarding Scientific Achievements?

Nuncius ◽  
2019 ◽  
Vol 34 (2) ◽  
pp. 317-355 ◽  
Author(s):  
Patrice Bret
Keyword(s):  
19Th Century ◽  
Royal Academy ◽  
The State ◽  
Future Research ◽  
Main Question ◽  
Technical Problems ◽  
Académie Des Sciences ◽  
Academy Of Sciences ◽  
The 19Th Century ◽  
Scientific Achievements

Abstract This study examines the science and technology prize system of the Académie des Sciences through a first survey of the prizes granted over the period extending from the 1720s to the end of the 19th century. No reward policy was envisaged by the Royal Academy of Sciences in the Réglement (statute) promulgated by King Louis XIV in 1699. Prizes were proposed later, first by private donors and then by the state, and awarded in international contests setting out specific scientific or technical problems for savants, inventors and artists to solve. Using cash prizes, under the Ancien Régime the Academy effectively directed and funded research for specific purposes set by donors. By providing it with significant extra funding, the donor-sponsored prizes progressively gave the Academy relative autonomy from the political power of the state. In the 19th century, with the growing awareness of the importance of scientific research, the main question became whether to use the prizes to reward past achievements or to incentivize future research, and the scale and nature of the prizes changed.

scholarly journals IX. Observations upon so much of Monsieur le Monnier the younger's memoir, lately presented to the Royal Society, as relates to the communicating the electric virtue to non-electrics; by Wm. Watson, F. R. S

1746 ◽  
Vol 44 (482) ◽  
pp. 388-395
Keyword(s):  
Royal Society ◽  
Royal Academy ◽  
The World ◽  
The Many ◽  
Academy Of Sciences

The World is much obliged to Mons. le Monnier for the many Discoverics he has made of the Power of Electricity; though the Reason of my troubling you with this Paper at this time, is my differing with that Gentleman in the Conclusions which he deduces from several of the Experiments contain’d in his Memoir lately presented to the Royal Academy of Sciences at Paris , his own Extract of which was lately communicated to the Royal Society .

XII. A letter from Richard Brocklesby M. D. and F. R. S. to the President, concerning the Indian Poison, sent over from M. de la Condamine, Member of the Royal Academy of Sciences at Paris

1746 ◽  
Vol 44 (482) ◽  
pp. 408-412 ◽  
Keyword(s):  
Natural History ◽  
Royal Academy ◽  
Academy Of Sciences

Honoured Sir , The Subjects of Natural History are often strange and uncommon; but the Authors who have treated on them have not failed, on their Parts, to support and raise the Wonder, and once conceived Astonishment, by ascribing Properties which never existed in Nature; thus indulging the Humour of finding a Marvellous in all Things, Truths have been greatly obscured, and Errors propagated without Number.

Spectral Sensitivity of Photoreceptors and Colour Vision in the Solitary Bee, Osmia Rufa

1988 ◽  
Vol 136 (1) ◽  
pp. 35-52
Author(s):  
R. MENZEL ◽  
E. STEINMANN ◽  
J. DE SOUZA ◽  
W. BACKHAUS
Keyword(s):  
Spectral Sensitivity ◽  
Colour Vision ◽  
Three Dimensional ◽  
Just Noticeable Difference ◽  
Species Discrimination ◽  
Colour Space ◽  
Absorption Function ◽  
Perceptual Distance ◽  
Line Elements ◽  
Colour Signals

The spectral sensitivity of single photoreceptors of Osmia rufa was determined by a fast voltage-clamp technique. Three receptor types were found whose spectral sensitivity functions followed a rhodopsin-like photopigment absorption function with λmax values at 348nm (ultraviolet receptor), 436nm (blue receptor) and 572nm (green receptor). The λmax of the green receptor in Osmia rufa is shifted to much longer wavelengths compared with other insect species. Discrimination of colour signals was tested after training a bee at the entrance to its nest. The colour signals were filter discs (70 mm in diameter) with a hole (10 mm in diameter) in the centre and the bees quickly learned to use the coloured disc as a marker of the nest entrance. Tests were dual forced-choice tests with two coloured discs closely positioned next to each other. 94 different tests were each repeated 5–15 times and were performed after training to 12 different colour signals. A photoreceptor model was used to calculate the loci of the colour signals in a three-dimensional colour space and in a chromaticity diagram. The perceptual distance between the colour loci was calculated as line elements (minimum number of just noticeable difference, jnd-steps), which were based on the noiseproperties of the photoreceptors. The discrimination determined by the behavioural tests correlated very well with the jnd-steps. The correlation was better for the line elements in the colour plane than in the colour space. Osmia rufa was compared with the honeybee Apis mellifera and the stingless bee Melipona quadrifasciata. There is no difference in colour selection between Osmia and Apis, whereas Melipona discriminates less well in the violet-blue region. The model calculation was used to compare the chromaticity diagrams and the spectral discrimination functions of the three species. It is concluded that the receptor model used in this study predicts the discrimination behaviour of the three bee species very well. Therefore, comparative studies on colour vision in flowervisiting insects may be based on spectral measurements of the photoreceptors, and in many cases this reduces the extent of laborious behavioural studies.

scholarly journals Royal Academy of Sciences and Arts of Barcelona

2013 ◽  
Vol 44 (3) ◽  
pp. 27-29
Author(s):  
Ramon Pascual
Keyword(s):  
Royal Academy ◽  
Academy Of Sciences
Sign in / Sign up

Export Citation Format

Share Document