“It is strange that you should take almost the identical line of thought that poor Peter Hardcastle took.  I hope to God you are right!”

“So far I am most certainly in the right.  We can leave the other world out of our calculations.”

He asked various questions, many of which did not appear to bear on the subject, but he made no suggestions as yet, and advanced no theories.  He suspected that Peter Hardcastle might have arrived at a conclusion had not death cut short his inquiry.  From time to time he lifted his hand gently for silence, and permitted a reply to penetrate his mind.

“I think very slowly about new things now,” he said.  “An idea must sink in gradually and find its place.  That is the worst of new ideas.  There is so little room for them when you are eighty.  The old and settled opinions fill the space, and are jealous and resent newcomers.”

Sir Walter explained to him presently that the room was being opened, and would be ready after luncheon.  Whereupon he expressed concern for the workers.

“Let them have a care,” he said, “for, if I am right, the danger is still present.  Let them work with despatch, and not loiter about.”

“No harm has ever undertaken more than one, when in the room alone.  The detectives saw and felt nothing.”

“Nevertheless, the assassin was quite equal to smudging out the detectives, believe me, Sir Walter.”

The day was fine, and Signor Mannetti expressed a wish to take the air.  They walked on the terrace presently, and Mary joined them.  He asked for her arm, and she gave it.

Prince padded beside her, and the visitor declared interest in him.

“Like myself, your dog is on the verge of better things,” he said.  “He will do good deeds in the happy hunting grounds, be sure.”

They told him the feats of Prince, and he appeared to be interested.

“Nevertheless, the faithful creature ought to die now.  He is blind and paralysis is crippling his hinder parts.”

Sir Walter patted the head of his ancient favorite.

“He dies on Friday,” he said.  “The vet will come then.  I assure you the thought gives me very genuine pain.”

“He has earned euthanasia, surely.  What is that fine tree with great white flowers?  I have seen the like before, but am sadly ignorant of horticulture.”

“A tulip-tree,” said Mary.  “It’s supposed to be the finest in Devonshire.”

“A beautiful object.  But all is beautiful here.  An English spring can be divine.  I shall ask you to drive me to primroses presently.  Those are azaleas—­that bank of living fire—­superb!”

He praised the scene, and spoke about the formal gardens of Italy.

Then, when luncheon was finished and he had smoked a couple of cigarettes, Signor Mannetti rose, bowed to Sir Walter, and said: 

“Now, if you please.”

They accompanied and watched him silently, while his eyes wandered round the Grey Room.