Suddenly he was startled by the report of a gun, and the next instant a bullet crashed through the glass of his window and buried itself in the opposite wall of the room.
Later on, when he investigated the incident, he found that the bullet had passed directly through the shadow of his head as it was cast upon the window shade, the person who fired it evidently supposing that his head was directly behind that shadow; but the fact that the light was at one side of the room, and had therefore thrown the shadow somewhat back of where he was actually seated, saved his life.
Further investigation disclosed the fact that the bullet had been fired from the rear of one of the houses in the block directly behind where the detective lived. It was not discovered how the would-be assassin had secured his position on the roof.
But this accumulation of accidents—so called for want of a better term—was altogether too much for the serenity and the composure of the detective and his assistants.
It was evident that Madge had determined to make his life miserable if it could be done, and when Nick recalled the substance of the letter she had sent him he decided in his own mind that the bullet had not really been intended to take his life, but only to warn him of the dangers that were hovering over him every minute that he lived.
In the meantime—or, rather, during the time that has already been mentioned—the detective and his assistants had not been idle. There had not been a day or a night when he and Chick and Patsy and Ten-Ichi had not been engaged in searching some part of the city for Black Madge, or for some trace of her.
They had visited the dens in the lower part of the city; they had questioned the policemen and the stool pigeons of the detective bureau, and they had even gone so far as to communicate directly with crooks who were known to them for information concerning the woman.
But none had been forthcoming. Black Madge was keeping herself as thoroughly under cover as if she were still in the prison in that other State from which she had escaped.
But after this occurrence of Sunday night, when the bullet was shot through the window at the detective, he determined to make no more half-hearted efforts to find Madge, but to set out at once that very night in search of her; and accordingly he put away his papers and called Chick into the room with him.
"Chick," he said, "do you happen to know anything about Mike Grinnel's place?"