He was found in his office dead, with a bullet in his body.

This is the bullet." Britz held the leaden pellet between his fingers, then laid it on the table.
"It was taken from Whitmore's body," he explained.

"It was fired from a 32-caliber revolver--in fact from this very weapon." From his coat pocket Britz produced the weapon, a gleaming steel revolver of the hammerless variety.
"Do you recognize it ?" he inquired, extending it toward Collins.
Collins's hand did not reach for the weapon.

All his confidence had vanished.

Fear seemed to paralyze him.
"That isn't all," proceeded the detective with aggravating assurance.
"The chambers in this revolver were filled from a box of fifty cartridges.