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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1851. Excerpt: ... placed alongside: the faithful copy of nature would reproduce on our organs the effect produced by the object itself; but we are obliged to compensate by a species of exaggeration, easily employed, for the imperfection of our means of imitation. ON THE CHANGES UNDERGONE BY COLOURS IN CERTAIN CIRCUMSTANCES. 101. After having treated of the modifications experienced by light in its absolute intensity, and of the colours of which it excites the sensation, it remains to examine what changes are produced in the colours themselves by the action of different modifying causes. This research belongs to the branch of optics which comprises the study of coloured light; it is much too vast to be here embraced in its entirety, and we shall confine ourselves to a few observations which we believe to be susceptible of frequent application. One of the principal causes of the variations of the colours consists in the nature of the luminous body; thus the cornflower of the fields, which is of a beautiful blue during the day, appears violet by candle-light; by the same light, the green of leaves and plants becomes much more sombre, and yellow approaches very nearly to a white tinged with pink: this is the reason why persons of not very fair complexions appear to more advantage by this light.. But the changes observed in colours do not proceed only from the nature of the light, either direct or reflected, with which they are illumined; they frequently arise, in part, from an imperfect appreciation that we form of colours when Our judgment is, so to speak, biassed by particular circumstances: witness the following examples. In the morning before sunrise, and when the sky is of a beautiful azure, if on a table before an open window a sheet of white paper and a candle be placed...
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- PublisherGeneral Books LLC
- Publication date2012
- ISBN 10 1150008156
- ISBN 13 9781150008153
- BindingPaperback
- Number of pages52
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