1923: The record of appeal in the case of the Iron Cap Copper Company against the Arizona Commercial Mining Company, both located in the Copper Hill District at Globe, is delivered to Superior Court. The record weighed more than 1,000 pounds and was delivered by an express company.
1926: A violent hailstorm hits Tucson, dropping temperatures 16 degrees in 20 minutes.
1939: Dancer Martha Graham performs in Tucson.
1971: St. Mary's opens intensive-care unit.
1994: The second Biosphere 2 crew — five men and two women — enters the sealed glass-and-steel structure near Oracle to begin the next phase of the $500 million project: routine operation as a laboratory for ecological research.
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