[1] In the original French Edition there is evidently a confusion of terms in this and the two following articles (39, 40, 41, 42). The Red is there represented as placed in juxtaposition with red, and green with green, and so on with the other instances; orange and blue; orange-yellow and indigo; greenish-yellow and violet; instead of being made by contrast with their respective complementaries to intensify each other.

[2] Hence the pleasure of reading books printed on the modern toned paper. De Morgan advises that tables of logarithms, and the like, should be printed on pale brown paper.

[3] It must be remembered that Chevreul speaks here of colours exclusively as to their optical effect, and that the very objection which he states to such an arrangement of colours, would be one of its best recommendations to the advocates of an obscure, in preference to a conspicuous uniform, as for Rifle Corps.