"I am too hungry to talk now. We will have dinner first."
The dinner was over at last, and nuts and coffee were before them, when Mr. Mitchel took a small parcel from his pocket, and handed it to Mr. Barnes, saying:
"It is a beauty, is it not?"
Mr. Barnes removed the tissue paper, and a large opal fell on the table-cloth, where it sparkled with a thousand colors under the electric lamps.
"Do you mean that this is——" cried the detective.
"The Aztec Opal, and the finest harlequin I ever saw," interrupted Mr. Mitchel. "But you wish to know how it came into my possession? Principally so that it may join the collection and cease to be a temptation in this world of wickedness."
"Then Mr. Gray did not steal it?" asked Mr. Barnes, with a touch of chagrin in his voice.
"No, Mr. Barnes. Mr. Gray did not steal it. But you are not to consider yourself very much at fault. Mr. Gray tried to steal it, only he failed. That was not your fault, of course. You read his actions aright, but you did not give enough weight to the stories of the others."
"What important point did I omit from my calculations?"
"I might mention the bare arms which Mrs. Gray said she felt around her neck. It was evidently Mr. Gray who looked for the opal on the neck of his sister-in-law, but as he did not bare his arms before approaching her, he would not have done so later."