Childermass keeps his eye on the other man as he backs out of the alley after Norrell, for if he is being honest with himself, he does not trust the word of a fae any further than he might be able to throw him. But the gun stays where it is on the ground, as do the two men stay in their places in turn, and it is after a long and careful glance in their direction that he finally turns to sweep after the other man. He will know if they are being followed. And they can bet that he will not be nearly so lenient on them if they do.