Complex sentence: After a stint in the United States Marine Hospital at Stapleton, Staten Island, he was selected by Surgeon General Walter Wyman and President William McKinley to study immigration abroad in Southampton, England where he traveled extensively throughout Europe from December 1899 to July 1900.
Split into simpler sentences: After a stint in the United States Marine Hospital at Stapleton, Staten Island, he was selected by Surgeon General Walter Wyman and President William McKinley to study immigration abroad in Southampton, England. From there, he traveled extensively throughout Europe from December 1899 to July 1900.