Columbia subject headings:
Harvard subject headings:
Authors, American--19th century--Biography
Mississippi River--Description and travel.
Missouri--Social life and customs.
River boats.
Twain, Mark, 1835-1910
Twain, Mark, 1835-1910--Childhood and youth.
West (U.S.)--Description and travel.
Princeton subject headings:
Authors, American--19th century--Biography.
Humorists, American--19th century--Biography.
Twain, Mark, 1835-1910.