The Unknown Quantity

Mary Boyne, who made shirts at four dollars a week, had no place for love in her life - only despair and hate for the son of the man who had plunged her family into deepest distress. Peter Kenwitz loved Mary, but because he was a mathematician and a pessimist by trade, his love was as hopeless as her chance for happiness.

• G. Marion BurtonWriter
• Thomas R. MillsDirector

• Corinne GriffithMary Boyne
• Huntley GordonDan Kinsolving
• Harry DavenportSeptimus Kinsolving
• Jack McLeanSammy Boyne
• Jack RidgewayThomas Boyne
• F.R. BuckleyPeter Kenwitz