The present article is based on photographs of nineteenth-century Arabic official letters, made by the author while carrying out conservation work on manuscript material for the Nigerian Department of Antiquities at the Northern Nigerian centres of Sokoto and Bauchi. Thanks to conscientious local custody, and the moisture-free atmosphere which these districts enjoy for most of the year, the greater number of these papers were still in remarkably good condition. At the same; time, progressive embrittlement of the fibres was making direct handling of the sheets undesirable, and some protection was felt necessary, The custodians of these collections had therefore been in touch with the Department of Antiquities, and it was decided as a first step to mount the most delicate and valuable specimens between sheets of glass, to be sealed at the edges with passe-partout and enclosed in light wooden frames.2 Since photo-graphy was likely to be more difficult after the completion of this work, the documents selected for treatment were first recorded upon 35 mm. film.