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Organic artefacts degrade by a number of mechanisms. Autoxidation is one of the most important and involves free radicals. The importance of free radical reactions in the degradation of paper and other cellulosic materials, rubber and other organics is described. In the case of paper, treatment with calcium and magnesium compounds can inhibit oxidation, while transition metals increase the rate. Antioxidants have not been used a great deal due to unwanted side effects. The Russell effect, a technique for detecting oxidation using photographic materials, is described.

The article makes a comparison of different washing techniques used on an artificially discolored, sized paper. The beneficial effects of increased temperature on washing were studied along with several other variables related to wetting of the paper. It was established that the Arches paper was (compared with filter paper) relatively difficult to wet and, when immersed in water, took several hours to achieve the maximum cleaning available by the immersion process. The experiments described in this article, study the relative efficiency of seven aqueous washing techniques used in paper conservation at the British Museum.

The rate of wetting and washing of paper was been studied in this article. The papers studied were an Arches artists' paper and a Whatman filter paper. The papers were used as supplied and as artificially discoloured by soaking them in a concentrated aqueous extract of old, discoloured paper. The wetting of the Arches paper was much slower than that of the filter paper; a surfactant accelerated the wetting of the Arches paper but had little effect on the filter paper. For both discoloured papers, the rate of washing was accelerated by the presence of surfactant. The rate of wetting and of washing was increased as the temperature increased. A period of storage at zero degree, relative humidity increased the extent of washing compared with paper previously humidified.