Aristide Valentin, Chief of the Paris Police, was late for his dinner, and some of his guests began to arrive before him. These were, however, reassured by his confidential servant, Ivan, the old man with a scar, and a face almost as grey as his moustaches, who always sat at a table in the entrance hall—a hall hung with weapons. Valentin's house was perhaps as peculiar and celebrated as its master. It was an old house, with high walls and tall poplars almost overhanging the Seine; but the oddity—and perhaps the police value—of its architecture was this: that there was no ultimate exit at all except through this front door, which was guarded by Ivan and the armoury. The garden was large and elaborate, and there were many exits from the house into the garden. But there was no exit from the garden into the world outside; all round it ran a tall, smooth, unscalable wall with special spikes at the top; no bad garden, perhaps, for a man to reflect in whom some hundred criminals had sworn to kill.

As Ivan explained to the guests, their host had telephoned that he was detained for ten minutes. He was, in truth, making some last arrangements about executions and such ugly things; and though these duties were rootedly repulsive to him, he always performed them with precision. Ruthless in the pursuit of criminals, he was very mild about their punishment. Since he had been supreme over French—and largely over European—policial methods, his great influence had been honourably used for the mitigation of sentences and the purification of prisons. He was one of the great humanitarian French freethinkers; and the only thing wrong with them is that they make mercy even colder than justice.