something to me of importance, and I put my head out of the window.

“May I ask you to keep an eye on my brother?” she whispered.

“In what way?” I asked, somewhat astonished.

The train began to move, and she walked to keep level with me.

“Do not let him drink at any of the railway buffets on the journey; he will be met at the Gare du Nord. He is addicted — ”

“But how can I stop him if he wants to — ”

She had an appealing look, and she was running now to keep pace with the train.

“Ah, do what you can, sir. I ask it as a favor. Pardon the request from a perfect stranger.”