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National Museum of Nuclear Science & History

John Chilton Horner “Doc” McDonnell

Scientist

Dr. John Chilton Horner McDonnell was believed to be involved in the Manhattan Project at the Naval Ordinance Station in Indian Head, Maryland where he was a research chemist.

Born Oct. 13 1920 in Fort Dade, Florida, McDonnell was raised in Warrenton, VIringia.  He received a BS from Catholic University and earned his Ph.D. in organic chemistry at the University of Chicago.

During World War II, McDonnell participated in the North Africa and Sicily campaigns during World War II from 1942 to 1944, working in chemical warfare. He then worked at the Naval Ordinance Station in Indian Head, Maryland, as a research chemist in the research and development division.

Dr. McDonnell, or “Doc,” married Beatrice Marie Martin in 1952. Beatrice was also a Manhattan Project veteran. Together they had four children.

McDonnell retired after 26 years of service with the Department of the Navy. During his career, Dr. McDonnell received a number of patents for this innovative research.

He died on September 26, 2000, preceded in death by his sister Austine Byrne McDonnell Hearst. Mrs. Hearst was married to William Randolph Hearst, Jr., the son of newspaper magnate, William Randolph Hearst. Their son William Randolph Hearst III lives in California.

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