Chromatics, or, An essay on the analogy and harmony of colours (1817)
Field, George, 1777?-1854 · London : Printed for the author by A.J. Valpy, Tooke's Court, Chancery Lane, and sold by Mr. Newman, Soho Square · leaf 68
Accordingly, for the purpose of the present illustration, two lenti- cular prisms were constructed, of which the following figures repre- sent outlines : — the first double convex , generated by the motion of a triangle round one of its sides, forming, as it were, a circular prism . the second… … Between these, as extremes, lies of course an infinite gradation of intermediate figures generated by the circular motion of a triangle laterally upon one of its angles : but these latter and other figures are beyond our present purpose. Exp. 5. To evince the concurrence of the principles of light…
Color
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