A waiter approached the table and addressed the Colonel—he was wanted on the telephone. During his absence, Heneage leaned back in his chair and relapsed into his usual imperturbability. He was known amongst his friends generally as the silent man. It was very seldom that he contributed so much to their discussions as upon this occasion. Perhaps for that reason his words, when he spoke, always carried weight. Mason changed his place and sat beside him. The others had wandered off into a discussion upon a new magazine.
"Between ourselves, Heneage," Mason said quietly, "have you anything at the back of your head about Wrayson?"
Heneage did not immediately reply. He was gazing at the little cloud of blue tobacco smoke which he had just expelled from his lips.
"There is no reason," he declared, "why my opinion should be worth any more than any one else's. I think as highly of Wrayson as any of you."
"Granted," Mason answered. "But you have a theory or an idea of some sort concerning him. What is it?"
"If you really want to know," Heneage said, "I believe that Wrayson has kept something back. It is a very dangerous thing to do, and I believe that he realizes it. I believe that he has some secret knowledge of the affair which he has not disclosed—knowledge which he has kept out of his evidence altogether."
"A—guilty—knowledge?" Mason whispered.
"Not necessarily!" Heneage answered. "He may be shielding some one."
"If you are right," Mason said anxiously, "it is a serious affair."
"Very serious indeed," Heneage assented. "I believe that he is realizing it."