“Surely,” said Inspector Blaikie, “after what I’ve just told you, there can’t be the shadow of a doubt about it.”
Superintendent Wilson gave a short laugh, and sat upright in his chair. He was beginning to enjoy himself.
“Ah, but I think there can. Come now. Let us take first only the murder of John Prinsep, leaving out of account for the moment the murder of George Brooklyn. Now, what evidence have you as to the murder of John Prinsep?”
“First, that Walter Brooklyn’s walking-stick has been found in his room, and secondly that Walter Brooklyn rang up from Liskeard House at about 11.30 that night. He must have rung up from Prinsep’s room. There are only two telephones in the building, one in the porter’s room downstairs, connecting with the offices on the ground floor, and the other, on a separate line, in Prinsep’s room. He couldn’t have used the downstairs ’phone, because it was out of order that night. Winter told me that.”
“Assume that you are right. Still, there is at least as strong evidence that George Brooklyn was in the room that night, too. Remember his handkerchief you picked up, and the draughtsman’s knife. And in any case he was seen leaving the house at 11.30, and we know from the discovery of his body in the grounds that he came back afterwards.”
“Yes, I know that,” said the inspector.
“And do you mean to tell me that, in face of that evidence, you can prove to a jury that it was Walter, and not George Brooklyn, who killed Prinsep?”
“Perhaps not, if the case were taken alone. But it has to be considered together with the other—the murder of George Brooklyn. The double incrimination seems to me decisive.”
“Wait a bit. Next let us take George Brooklyn’s case, leaving aside for the moment that of Prinsep. Now, there, what evidence have you?”
“The finding of the ferrule in the garden, and the strong motive Walter Brooklyn had to put both nephews of Sir Vernon out of the way.”