Annihilation by Isabel Ostrander

Dennis' lacerated emotions were finally soothed and after an old oil lamp was resurrected from the store-closet and lighted he seated himself for a pipe and a chat, but the shock had disorganized him beyond concentration on the case and he departed early for the fire house.

McCarty had carefully kept his bulk between his visitor and the sight of what lay in the fireplace and the moment the latter went away he removed the death-dealing paraphernalia and locked it in his bedroom closet beneath a pile of old boots, together with the revolver. This had proved on examination to be a replica of his own old service one. How could his would-be assassin have come into possession of a "police positive," a .38 manufactured for the department alone?