He was later to become 31st President of the United States ( 1929 -- 1933 ) .
Hoover was appointed Superintendent of the Sons of Gwalia Mine and managed it from May to November 1898 before moving on to China .
Hoover was later to become 31st President of the United States ( 1929 -- 1933 ) .
Hoover was appointed Superintendent of the Sons of Gwalia Mine and managed it from May to November 1898 before moving on to China .