Unpublished paper, 'Duplication du cube' [Cube duplication] by Bardel Bardel begins by presenting the problem of doubling the cube, or the Delian problem. He proceeds to demonstrate his solution to the problem. Includes six pages of figures separate to the text illustrating Bardel's geometric method. Followed by two covering letters addressed to the President of the Royal Society and [John George] Children respectively. Subject: Mathematics / Geometry Received 5 July 1838. Written by Bardel at 24 Rue Guénégaud, Paris. 1838-1839