It seems from what I heard-I can't recall the exact words-that not very long ago, the night watchman in the offices was Chloroformed and the safe ransacked, but nothing was taken except a letter.
"The Crevice"
William John Burns and Isabel Ostrander
He had no idea where the black limousine had taken him, for it had traveled a devious course, and he had been Chloroformed before it reached its destination.
"The Gray Phantom's Return"
Herman Landon
I must have been Chloroformed, for shortly afterward I lost consciousness.
"The Gray Phantom's Return"
Herman Landon