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Featured Article: Federalist No. 23
Alexander Hamilton, author of Federalist No. 23
Popular Article: Silurian
The Silurian period is an interval of about 28 million years defined on the geologic timescale as spanning roughly from 444 to 416 million years ago (mya) and lying between the earlier Ordovician period and the later Devonian period. As with other geologic periods, the rock beds defining the period's start and end are well identified, but the exact dates are uncertain by five to ten million years. The base of the Silurian is set at a major extinction event when 60 percent of marine species were wiped out.
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General Robert E. Lee's surrender at Appomattox Courthouse on April 9, 1865, is commonly viewed as signifying the end of the American Civil War (source: Robert E. Lee)