Benedikt, Rudolf, 1852-1896, Knecht, Edmund, 1861-1925 · London : G. Bell and Sons · leaf 33
spectrum 3, which is characteristic for the green produced by means of indigo extract and picric acid. It consists of blue, bluish-green, green, and a portion of the red. Indigo extract and picric acid do not, therefore, as may have been supposed, yield a green because one allows only blue rays,… … Fig. 11. a pure blue colouring matter which would not yield a green with a pure yellow colouring matter possessing the absorption-spectrum 2, since all the rays would be absorbed and the result would be a hlack. If the spectra of these two colouring matters are en- larged on each side, the single…
Coal-tar colors
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