Identification & Site Information

  • Vessel Name(s): Foolkiller (nickname assigned after discovery)
  • Original Name/Type: Unknown; likely experimental submersible or lifeboat
  • Approximate Construction Date: Mid- to late-19th century (speculative, pre-1880s)
  • Dimensions:
    • Length: ~40 ft (12.2 m)
    • Estimated Beam: ~6 ft (1.8 m)
  • Hull Material: Metal (type undetermined, likely boiler iron or steel)
  • Propulsion: Unknown; possibly hand-cranked or treadle-driven propeller
  • Rigging: None (submersible)
  • Original Function:
    • Believed in 1915 to be a 19th-century experimental submarine
    • Recent research suggests it was more likely an experimental life boat/submersible escape craft

Location of Discovery:

  • Body of Water: Chicago River, Illinois
  • Discovery Year: 1915
  • Depth at Discovery: Buried in mud below the river bottom
  • Exact Coordinates: Unrecorded; near downtown Chicago riverfront

Discovery & Examination (1915)

  • Discovered by: William “Frenchy” Deneau, a diver contracted for Chicago River cleaning and salvage.
  • Condition:
    • Found completely buried in river mud.
    • Contained skeletal remains of a man and a dog, suggesting it sank with occupants inside.
    • Vessel described as cigar-shaped, iron-clad, with rudimentary conning tower openings.

Initial Public Reaction:

  • Chicago newspapers dubbed it the “Foolkiller”, implying the inventor perished in his own contraption.
  • Widely reported as a mysterious lost Civil War-era or post-war submarine.

Exhibit & Disappearance

  • 1916: Vessel raised and placed on exhibit at Riverview Park, a popular Chicago amusement park.
  • Displayed as a curiosity submarine, with admission charged to view the interior.
  • Shortly after, the vessel vanished:
    • No records of sale, destruction, or return to the river.
    • Presumed scrapped or lost to private ownership.

Theories on Origin

  • 19th-Century Experimental Submarine
    • Fits the cigar-shaped iron Hull description.
    • Similar to Brutus de Villeroi-style Civil War submersibles or independent inventors’ craft.
  • Experimental Lifeboat / Submersible Escape Craft (current leading theory)
    • Patent research indicates multiple 1860–1890 “submersible lifeboat” patents from the Great Lakes and Chicago region.
    • Possibly an unregistered or failed prototype Abandoned after a fatal test.
  • Homemade Submarine (“Inventor’s Folly”)
    • Media title Foolkiller reinforces the idea that it was privately built, non-military, and unsuccessful.

Casualty & Human Element

  • Remains Discovered (1915):
    • One adult male skeleton
    • One dog skeleton
  • Identities: Never determined
  • Burial or Memorial: No formal records found; remains likely interred in Chicago potter’s field or disposed after coroner review.

Final Disposition

  • Current Status: Unknown (disappeared post-1916)
  • Last Known Location: Riverview Park exhibit, Chicago
  • Fate: Presumed scrapped, sold privately, or destroyed

Historical Significance

The Foolkiller is a key unsolved mystery in Great Lakes and Chicago maritime history because:

  • Represents experimental submersible technology on inland waters before widespread adoption.
  • Connects to the tradition of private “inventor subs” that paralleled early U.S. Navy developments.
  • The disappearance of the vessel leaves a gap in documentation that complicates verification.

If rediscovered, it would be a rare example of midwestern 19th-century submersible technology, comparable to:

  • The Turtle (1775)
  • CSS Hunley (1863)
  • Other Great Lakes experimental subs, e.g., the 1897 Porcupine (Detroit River)

Resources & References

  • Chicago Tribune (Nov. 1915, Feb. 1916) – Foolkiller discovery and Riverview exhibit
  • Illinois State Historical Library, Chicago River salvage files
  • Riverview Park Archive, Chicago History Museum (archival photos & news clippings)
  • Great Lakes Submarine Inventors and Prototypes (1850–1900) – unpublished notes from WHS & NOAA archives