Timeline of the San Francisco Earthquake April 18 - 23, 1906

http://www.sfmuseum.org/hist10/06timeline.html

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At about 10:05 a.m. the DeForest Wireless Telegraph Station at San
Diego radioed press reports of the disaster at San Francisco to the
"U.S.S. Chicago." Admiral Caspar Goodrich immediately ordered fires
started under all boilers, and after a confirmation message from the
Mayor of San Diego, the "Chicago" steamed at full speed for San
Francisco. It was the first time wireless telegraphy was used in a
major natural disaster.
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