It immediately occurred to the Wanderer that he could ring the bell.

But disliking the idea of entering into an explanation, he reserved that for an emergency.
Had he attempted it he would have been still further surprised to find that it would have produced no result.

In going through the vestibule Keyork had used Kafka's sharp knife to cut one of the slender silk-covered copper wires which passed out of the conservatory on that side, communicating with the servants' quarters.

He was perfectly acquainted with all such details of the household arrangement.
Keyork's precautions were in reality useless and they merely illustrate the ruthlessly selfish character of the man.

The Wanderer would in all probability neither have attempted to leave the house with Kafka that night, nor to communicate with the servants, even if he had been left free to do either, and if no one had disturbed him in his watch.