The fact of the presence of the chambermaid--who had come to clean up The Yellow Room--in the laboratory, when Monsieur Stangerson and his daughter returned from their walk, at half-past one, permits us to affirm that at half-past one the murderer was not in the chamber under the bed, unless he was in collusion with the chambermaid.

What do you say, Monsieur Darzac ?" Monsieur Darzac shook his head and said he was sure of the chambermaid's fidelity, and that she was a thoroughly honest and devoted servant.
"Besides," he added, "at five o'clock Monsieur Stangerson went into the room to fetch his daughter's hat." "There is that also," said Rouletabille.
"That the man entered by the window at the time you say, I admit," I said; "but why did he shut the window?
It was an act which would necessarily draw the attention of those who had left it open." "It may be the window was not shut at once," replied the young reporter.
"But if he did shut the window, it was because of the bend in the gravel path, a dozen yards from the pavilion, and on account of the three oaks that are growing at that spot." "What do you mean by that ?" asked Monsieur Darzac, who had followed us and listened with almost breathless attention to all that Rouletabille had said.
"I'll explain all to you later on, Monsieur, when I think the moment to be ripe for doing so; but I don't think I have anything of more importance to say on this affair, if my hypothesis is justified." "And what is your hypothesis ?" "You will never know if it does not turn out to be the truth.

It is of much too grave a nature to speak of it, so long as it continues to be only a hypothesis." "Have you, at least, some idea as to who the murderer is ?" "No, monsieur, I don't know who the murderer is; but don't be afraid, Monsieur Robert Darzac--I shall know." I could not but observe that Monsieur Darzac was deeply moved; and I suspected that Rouletabille's confident assertion was not pleasing to him.

Why, I asked myself, if he was really afraid that the murderer should be discovered, was he helping the reporter to find him?
My young friend seemed to have received the same impression, for he said, bluntly: "Monsieur Darzac, don't you want me to find out who the murderer was ?" "Oh!--I should like to kill him with my own hand!" cried Mademoiselle Stangerson's fiance, with a vehemence that amazed me.
"I believe you," said Rouletabille gravely; "but you have not answered my question." We were passing by the thicket, of which the young reporter had spoken to us a minute before.

I entered it and pointed out evident traces of a man who had been hidden there.