French physicist (1892-1987) known for his theory that matter has the properties of both particles and waves, who was awarded the 1929 Nobel Prize in Physics. Two ALSs, in French, both one page, both sides, 6 x 4 and 4.75 x 3.5, dated March 12 and 22, 1951, respectively both to Henriette Craponne-Eudel, General Secretary of "Assistance Privée a la Classe Moyenne [Private Help for the Middle Class]." Both letters refer to his lecture on Atomic Energy at the Sorbonne. One reads, in part (translated): "I had much pleasure in being of service to the A.P.C.M by delivering my lecture on Atomic Energy...Madame Fieves writes me about the possibility of publishing my lecture. I've already promised the text to Mr. Chouneix of the Revue des deux mondes but that needn't prevent the making of a Special edition if you think it useful...l'm entirely at your service...for the publication of my lecture...Can you have a dozen programs sent to me...I'll be glad to autograph programs for Mrs. Gabriel Robinet and Dr. Crivelli." In overall fine condition.