- Our Landed Heritage: The Public Domain in the American West (1962)
- Wisconsin North (1962)
- The Diary of Colonel Archibald Gracie (1961)
- This Awful Civil War (1959)
- The Man behind the Gun (1958)
- The Last of the Whaling Captains (1954)
- William F. Cody (1950)
- The Tragedies of 1812: The Story of the War Hawks and the War They Forced (1951)
- Hidden America (1948)
- Walt Whitman and Herman Melville (1941)
- The Unknown South (1940)
- The Cowboy, When the Wild West Was Wild (1936)
- Men and Monsters: The Strange Story of an Island Empire (1936)
- Our Landed Heritage: The Public Domain, 1776–1936 (1936)
- The Lost Language of Symbolism: The History of Symbols and Their Meanings in the Great World Religions (1930)
Short Stories:
- "The Ghost of Iron Mike" (1930)
- "The Mystery of the Green Ray" (1929)
- "The Voice in the Night" (1928)
- "The Haunted House" (1927)
- "The Vampire" (1926)
- "The Werewolf" (1925)
- "The Mummy" (1924)
- "The Phantom of the Opera" (1923)
- "The Hunchback of Notre Dame" (1922)
- "The Island of Dr. Moreau" (1921)