His mind resumed its composure, and he watchfully waited the return of the slave.
Suddenly he was conscious of some one behind him, though he had heard no one approach.

He swung round and was met by the passive face of the black slave in personal attendance on Harrik.

The slave did not speak, but motioned towards a screen at the end of the room, and moved towards it.

David followed.

As they reached it, a broad panel opened, and they passed through, between a line of black slaves.