It was equally obvious then that Whitey Mack would know the Gray Seal as Larry the Bat.

Did he also know him as Jimmie Dale?
Yes, or no?
It was a vital question.

His life hung on it.
That keen, facile brain, numbed for the moment, was beginning to work with lightning speed.

It was four o'clock that afternoon when he had assumed the character of Larry the Bat--some time between four o'clock and the present, it was now well after eleven, the case had dropped from his pocket.

There had been ample time then for Whitey Mack to have made that appointment with Lannigan--and ample time to have made a surreptitious visit to the Sanctuary.