Le fauteuil mécanique de Georges Couthon (XVIIIe siècle, musée Carnavalet) : recherche sur les films plastiques transparents utilisables pour la protection des textiles d'ameublement. Essai de détermination des critères de choix

This thesis deals with the study and conservation treatment of an 18th century wheelchair, stored in the Musée Carnavalet - the Museum of the History of Paris. In addition to its unique design, this chair has conserved its original upholstery. The textile elements had never been removed, partially because the chair was once owned by Georges Couthon (1755-1794), a great figure of the French Revolution, and a close ally of Maxiilien Robespierre. According to historical documents, the disable deputy used the seat a few times, before its execution at the end of the Terror period. The Couthon's chair treatment ilustrate the complexity of upholstery. The damaged wheelchair needed to be treated respecting its original materials and appearance. Whereas the velvet covering the seat has only been partially consolidated (with a non-intrusive method), the back has been detached, in order to restore each element of the upholstery. The re-upholstering has been a collaboration project between a textile conservator and an upholosterer who was incharge to restitute the original appearance of the chair. Finally, the scientific research has been focused on the study of the transparent plastic films, used in museums for the protecion of upholstered furniture. The purpose was to determine choice criteria, and to test selected samples in order to improve the quality of the products frequently used. Their optical properties, as well as well as their innocuousness have been tested.