The Unknown Quantity
- Godina: 1919
- Country: United States of America
- Žanr: Drama
- Studio: Vitagraph Company of America
- Ključna riječ: lost film
- Direktor: Thomas R. Mills
- Uloge: Corinne Griffith, Huntley Gordon, Harry Davenport, Jack McLean, Jack Ridgeway, F.R. Buckley
