Secret societies
Free to read here, from Project Gutenberg.
The unknown seven
The Big Four
Secret societies and subversive movements
The Mide'wiwin or "Grand Medicine Society" of the Ojibwa
The Double Four
The Knights of the Round Table: Stories of King Arthur and the Holy Grail
Eastern Standard Tribe
Mysticism and its results
Secret Societies of the Middle Ages
The Return of Dr. Fu-Manchu
The Molly Maguires and the detectives
Fire-Tongue
Blind Love
Mysteria
Peter Ruff and the Double Four
The Black Cross
Secret Societies: A Discussion of Their Character and Claims
What is POSAT?
Little Prudy's Cousin Grace
The war of Antichrist with the Church and Christian civilization
A Dead Reckoning
Delenda est Carthago!
Mark Tidd: His Adventures and Strategies
The fourth plague