Bichromate Sausages
Just for fun, here's the passage referred to, from Vogel's 'The Chemistry of Light and Photography in their Application to Art, Science, and Industry' (mine is 6th, ed., 1892): Section XII. - THE CHEMICAL ACTION OF LIGHT, AND THE PEA-SAUSAGE.* In the campaign of 1870, the well-known pea-sausage was one of the most important articles of food for the army, and was prepared daily by thousands. The fabrication of the interior portion caused little difficulty, but the obtaining so many skins created much difficulty. As the supply fell short, a substitute was sought in vegetable parchment. This paper, which is produced by dipping blotting-paper in sulphuric acid for about a second, then washing and drying, is distinguished by its skin-like properties of resistance. It is impenetrable to water, and difficult to tear. It is therefore used for the production of bank-notes. It was attempted to make sausage skins of this paper, by doubling a skin cylindrically and pasting it together. No glue or gum can however resist the effect of the boiling water in which the sausage has to be cooked, and so the artificial sausage skin fell asunder. Dr. Jacobson solved the problem by producing an adhesive substance, with the help of the chemical action of light, which could resist boiling water. He mixed the glue intended for the sausage skin with bichromate of potash, and exposed the glued parts to the light. This made the glue insoluble, and now the artificial skin endured boiling water thoroughly well. The number of sausage skins prepared in this way, by the chemical action of light, amounted to many hundred thousands. * Erbswurst. Liam
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