"Because primarily we were concerned with making the criminal himself or herself divulge the secret."
"That's why you would not allow the loss to be made known," broke in
Mr. Llewellyn John.
"The thief," continued Malcolm Sage, with a slight inclination of his head, "would in all probability seize the first safe opportunity of getting rid of the plunder."
"But did you not suspect the Japanese?" broke in Lord Beamdale.
"For the moment I ruled him out," said Malcolm Sage, "as I could not see how it was possible for him to know about the existence of the document in question, and furthermore, as he had been in the house less than two days, there was no time for him to get a duplicate key."
"What did you do then?" queried Sir Lyster.
"I motored back to town, broke in upon the Postmaster-general's first sleep, set on foot enquiries at the Admiralty and War Office, in the meantime arranging for The Towers to be carefully watched." Malcolm Sage paused for a moment; then as none of his hearers spoke he continued:
"I had a number of people in the neighbourhood—motorists, cyclists, and pedestrians. No one could have left the house and grounds without being seen.
"Miss Blair found the morning irresistible, and took an early spin on her bicycle to Odford, where she posted a packet in a pillar-box situated in a street that was apparently quite empty."
"And you secured it?" enquired Mr. Lewellyn John, leaning forward eagerly.