And then he explained to me that this great painter (great even then, though as yet appreciated only in certain choice Parisian circles, and not known out of France) was at work upon a grand historical subject connected with the Spanish persecutions in the Netherlands—­the execution of Egmont and Horn, in short, in the great square before the Hotel de Ville in Brussels.

“But the main point now,” said Mueller, “is to get the sketch—­and how?  Confound the fellow! while he keeps his back to the light and his head down like that, the thing is impossible.  Anyhow I can’t do it without an accomplice.  You must help me.”

“I!  What can I do?”

“Go and sit near him—­speak to him—­make him look up—­keep him, if possible, for a few minutes in conversation—­nothing easier.”

“Nothing easier, perhaps, if I were you; but, being only myself, few things more difficult!”

“Nevertheless, my dear boy, you must try, and at once.  Hey —­presto!—­away!”

Placed where we were, the stranger was not likely to have observed us; for we had come into the room from behind the corner in which he was sitting, and had taken our places at a table which he could not have seen without shifting his own position.  So, thus peremptorily commanded, I rose; slipped quietly back into the inner salon, made a pretext of looking at the clock over the door; and came out again, as if alone and looking for a vacant seat.

The table at which he had placed himself was very small—­only just big enough to stand in a corner and hold a plate and a coffee-cup; but it was supposed to be large enough for two, and there were evidently two chairs belonging to it.  On one of these, being alone, the stranger had placed his overcoat and a small black bag.  I at once saw and seized my opportunity.

“Pardon, Monsieur,” I said, very civilly, “will you permit me to hang these things up?”

He looked up, frowned, and said abruptly:—­

“Why, Monsieur?”

“That I may occupy this chair.”

He glanced round; saw that there was really no other vacant; swept off the bag and coat with his own hands; hung them on a peg overhead; dropped back into his former attitude, and went on reading.

“I regret to have given you the trouble, Monsieur,” I said, hoping to pave the way to a conversation.

But a little quick, impatient movement of the hand was his only reply.  He did not even raise his head.  He did not even lift his eyes from the paper.

I called for a demi-tasse and a cigar; then took out a note-book and pencil, assumed an air of profound abstraction, and affected to become absorbed in calculations.

In the meanwhile, I could not resist furtively observing the appearance of this man whom a great artist had selected as his model for one of the darkest characters of mediaeval history.