'Who is that?'
`The chief of staff in charge of the army hospital here. I told Dalrye to go to the White Tower and find Mr Radburn, the chief warder. He generally finishes his afternoon round at the White Tower at two-thirty. I also told him to leave instructions that nobody was to leave the Tower by any gate. I knew it was a useless precaution, because Driscoll had been dead some time and the murderer had every opportunity for a getaway; but it was the only thing to do.'
`Just a moment,' interposed Hadley. `How many gates are there through the outer walls?'
`Three, not counting the Queen's Gate, nobody could get through there. There's the main gate, under the Middle Tower, through which you came. And two more giving on the wharf. They are both in this lane, by the way, some distance farther down.'
`Sentries?'
`Naturally. A Spur Guard at every gate, and a warder also. But if you're looking for a description of somebody who went out, I'm afraid it's useless. Thousands of visitors use those gates every day. Some of the warders have a habit of amusing themselves by cataloguing the people who go in and out, but it's been foggy all day and raining part of the time. Unless the murderer is some sort of freak, he had a thousand-to-one chance of having escaped unnoticed.'
`Damn!' said Hadley, under his breath. `Go on, General.'
`That's about all. Dr Benedict — he's on his rounds now — confirmed my own diagnosis. He said that Driscoll had been dead at least three-quarters of an hour when I found him, and probably longer?
General Mason hesitated.
`There's a strange, an incredible story concerned' with Driscoll's activities here this afternoon. Either the boy went mad, or.. another sharp gesture. `I suggest that you look at him, Mr Hadley; then we can talk more comfortably in the Warders' Hall.'