If those men outside could shed any light on the crime, they would do so eagerly.

The murderer could not have enjoined silence on thirty or thirty-five men.

No, they have told all they know.
You may permit them to enjoy their lunch." Although the coroner was the ranking official, his respect for Britz's judgment was such that he invariably followed the latter's suggestions.
So he informed the clerks they could leave the building at will.
While the coroner was in the big room addressing the employes, Britz suddenly walked to the chair in which the murdered man still sat huddled.

Bending down, he picked up something long and shiny, which the others had overlooked.

It was a long darning needle, and the detective, after examining it an instant under the electric light, slipped it into a leather card case.