Statistics for occurrence #1 of “Fleet-captain Charles H. Davis” in page 128 of Benson J. Lossing, Pictorial Field Book of the Civil War. Volume 2.:
...s, from New Bedford and New London, were sunk on the bar at the entrance of the Main Ship channel, six miles in a direct southern line from Fort Sumter.
This was done under the superintendence of Fleet-captain Charles H. Davis .
They were placed at intervals, checkerwise, so as to form
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