“To me, I presume you mean;” then when he bowed, she continued her examination.  “The five thousand pounds you intimate is on account, yet you say that Chaldea will deliver the letter for that sum.”

“To me,” rejoined the ex-secretary impudently.  “And when it is in my possession, I can give it to you for twenty thousand pounds.”

Lady Agnes laughed in his face.  “I am too good a business woman to make such a bargain,” she said with a shrug.

“Well, you know best,” replied Silver, imitating her shrug.

“I know nothing; I am quite in the dark as to the reason for your blackmailing, Mr. Silver.”

“That is a nasty word, Lady Agnes.”

“It is the only word which seems to suit the situation.  Why should I give twenty-five thousand pounds for this letter?”

“Its production will place the police on the track of the assassin.”

“And is not that what I desire?  Why did I offer a reward of one thousand pounds if I did not hope that the wretch who murdered my husband should be brought to justice?”

Silver exhibited unfeigned surprise.  “You wish that?”

“Certainly I do.  Where was this letter discovered?”

“Chaldea went to the tent of your husband in the camp and found it in the pocket of his coat.  He apparently left it behind by mistake when he went to watch.”

“Watch?”

“Yes!  The letter stated that you intended to elope that night with Mr. Lambert, and would leave the house by the blue door.  Sir Hubert went to watch and prevent the elopement.  In that way he came by his death, since Lord Garvington threatened to shoot a possible burglar.  Of course, Sir Hubert, when the blue door was opened by Lord Garvington, who had heard the footsteps of the supposed burglar, threw himself forward, thinking you were coming out to meet Mr. Lambert.  Sir Hubert was first shot in the arm by Lord Garvington, who really believed for the moment that he had to do with a robber.  But the second shot,” ended Silver with emphasis, “was fired by a person concealed in the shrubbery, who knew that Sir Hubert would walk into the trap laid by the letter.”

During this amazing recital, Lady Agnes, with her eyes on the man’s face, and her hands clasped in sheer surprise, had sat down on a near couch.  She could scarcely believe her ears.  “Is this true?” she asked in a faltering voice.

Silver shrugged his shoulders again.  “The letter held by Chaldea certainly set the snare in which Sir Hubert was caught.  Unless the person in the shrubbery knew about the letter, the person would scarcely have been concealed there with a revolver.  I know about the letter for certain, since Chaldea showed it to me, when I went to ask questions about the murder in the hope of gaining the reward.  The rest of my story is theoretical.”

“Who was the person who fired the shot?” asked Lady Agnes abruptly.

“I don’t know.”