UPDATE: "Two Dozen (Nearly) Detectives All in One Place"

Story links added or altered (HERE) for:

   - "The Unknown Murderer" by H. C. Bailey

   - "The Disappearance of Mr. Davenheim" by Agatha Christie

   - "Homespun Silk" by Octavus Roy Cohen

   - "The Treasure Hunter" by Melville Davisson Post and

   - "The Treasure Hunt" by Edgar Wallace.