put him on, dressed like a loafer, to hang about Whitehall and the neighbourhood, watching for some one we want. Well, this morning there came an urgent message to the Yard from the Admiralty, to ask for a responsible official at once, and I was sent. As I came along I saw Corder lounging about, and of course I took no notice—it would not do for us people from the Yard to recognise each other too readily in the street. But Corder came up, and made pretence to ask me for a match to light his pipe; and under cover of that he told me that he had seen Mayes not an hour before, coming out of the Admiralty. At this, of course, I pricked up my ears. I didn't know what they wanted me for, but if there was mischief, and that fellow had been there, it was likely at least that he might have been in it. Corder was quite positive that it was the man, although he had only seen him for a moment in the lift. He hadn't seen him go into the Admiralty office, but he was passing as he came out, and noted the time exactly, so that he might report to me at the first opportunity. The time was 11.32, and Mayes jumped into a hansom and drove off. He walked right out into the middle of the road to stop the hansom—you know how wide the road is there—so that Corder couldn't hear his direction to the cabman, but he took the number as the cab