Bacteriologist (1853–1933). He studied at Clermont-Ferrand, became assistant to Pasteur, and was appointed his successor. In 1894 he helped to discover diphtheria antitoxin, and also worked on rabies and anthrax. ALS in French, signed “D. Roux,” one page, 4.25 x 7, Institut Pasteur letterhead, September 20, 1895. Letter to the director of the Biographical Review. In part (translated): “I’m returning to you the corrected proofs of the biographical notice concerning me. It is full of errors. The discovery of an anti-diptheria Serum is attributed to me. It is Mr. Behring’s [Emil Adolf von Behring discovered diphtheria antitoxin in 1890]. All I did was make practical application of it. I insist on the notice being printed just as I have corrected it. That way it’s exact.” In fine condition, with a mild shade of toning, a bit heavier to left edge. RRAuction COA.