Notes on Foreign Inventions. Restoring Faded Scarlet Colors.

The Scientific American 18, 29.10.1859

Next to deep indigo blue, scarlet colors are perhaps the most expensive to produce on woollen fabrics, because cochineal, a very dear drug, is employed in the process. This color, although very showy, is very easily stained with iron rust, which makes it brown, or with an alkali, which changes it into a dingy crimson. To restore this color on fine woollen cloth, G. T. Bousfield, of London, has secured a patent for the following mixture: - Citric acid, 300 grains; carbonate of potash, 150 grains; water, 7,500 grains. The citric acid is to be dissolved separately in 4,500 grains of water, and the carbonate of potash in 3,000. The whole is then mixed together and applied with a sponge. A very dilute solution of the muriate of tin is a better mixture for this purpose than the citric acid and alkaline solution. After being applied, and the stain removed, the spot is washed with warm water. Red military coats and facings, which have become stained with iron rust from the musket, may be renewed in this manner.