LANDSCAPE PAINTING
oil and the varnish dry at different rates of speed. The pictures of Rubens and Vandyke were varnished with a medium made by exposing pure linseed oil to the sunlight until it was quite thick. This required a month or two to dry thoroughly after it was applied to the picture; but the splendid preservation and the great brilliancy of Rubens's pictures have justified all the extra pains and trouble incident to the method which he employed.
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