Page:Landscape Painting by Birge Harrison.djvu/156

LANDSCAPE PAINTING results a general browning or greening of the whole picture. The rule, then, is either to content ourselves with zinc white, or, if white lead is used, to cast aside the cadmiums, vermilion, and emerald green (which, having a copper basis, is also subject to change when brought into contact with sulphur). The vermilion, fortunately, has now been replaced by the new color (which has been named by its makers Harrison red); and the cadmiums are hardly necessary, as they can be replaced by the chromes. Thus, with either lead white or zinc white, we have a very extended range, which has been greatly strengthened of late years by the addition of the two superb and perfectly safe alizarine colors, the scarlet and the crimson varieties. Neither the yellow nor the green alizarine can yet be claimed as perfectly [116]