SEGUIN Jean-Marie (1823-1913) physicist. MANUSCRIT autograph signed " JM Seguin ", Résumé d'une thèse de Physique, Sur les couleurs accidentelles, Paris, April 23, 1851; small notebook in-4 of 1-7 pages. The first page is sent to César DESPRETZ, "member of the Institute, Professor at the Faculty of Sciences". It is the summary of the thesis of this physicist from Carpentras, presented at the Faculty of Sciences of Paris on May 17, 1852, and which will be published the same year (Sur les couleurs accidentelles, Caen, 1852). It is divided into two parts: I "Accidental colors which result from the contemplation of a white object"; II "Accidental colors which result from the contemplation of colored objects".