"The man you saw was in this house, to my certain knowledge, once before--while M. Felix was alive. Your aunt did not know it; M. Felix opened the street door for him. It was the night M. Felix was found dead, and when the man went away he took a desk with him that belonged to M. Felix."
Sophy nodded. "Aunty's spoke to me about that desk. She never could make out, she ses, what 'd become of it."
"I will describe it to you, Sophy." I did so, and she listened attentively, nodding from time to time with surprising intelligence. "If you happen to see this desk in the possession of the man whom I look upon as my enemy, do you think you could identify it?"
"Know it again? Yes, I should. But 'ow am I to git to the man?"
"I have thought of a plan, or rather a friend of mine has, which requires courage to carry it out successfully. It requires something more than courage; without great good sense and coolness the plan would fail. The question is whether you possess those qualities."
"It ain't no question at all; I've got what you want, and can do what you want."
"There is something in the desk, Sophy, that is of the utmost importance to me."
"And I'm to git it for yer. All right. Smuggle me into the 'ouse, and consider it done."
"But you don't know what kind of a place it is, my girl. It's a private madhouse." Sophy did not blench; she simply nodded, and fixed her large brown eyes on my face. "The man's name," I continued, "is Peterssen, Dr. Peterssen. If he wanted a young girl as a servant you should apply for the situation, but I don't think there is a vacancy in his establishment. He is ready to take more patients, though, and he likes young patients better than old ones."
"You're going to put me in there as a mad gal," cried Sophy, in a tone of irrepressible excitement, which lasted, however, only for a moment. She cooled down instantly, and said in her usual tone, "Crikey! That's a good move. I'm game! It's a good part to play, and no mistake."