“Yes; his brother, Colonel Valentine Walter, has testified to his departure from Woolwich, and Admiral Sinclair to his arrival in London; so Sir James is no longer a direct factor in the problem.”

“Who was the other man with a key?”

“The senior clerk and draughtsman, Mr. Sidney Johnson. He is a man of forty, married, with five children. He is a silent, morose man, but he has, on the whole, an excellent record in the public service. He is unpopular with his colleagues, but a hard worker. According to his own account, corroborated only by the word of his wife, he was at home the whole of Monday evening after office hours, and his key has never left the watch-chain upon which it hangs.”

“Tell us about Cadogan West.”