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July 8, 1926. Washington, D.C. "Miss Hattie E. Alexander & Mrs. S.A. Carlin testing serum." View full size. National Photo Company Collection. [Update: A few years after this photo was taken, Hattie (on the left) would become Dr. Alexander. As president of the American Pediatric Society in the 1960s, she was among the first women to head a major medical association.]