H.M. looked uncomfortable.

"Oh, my son! I didn't know! It was only one of about eight possibilities, where I had to block the approach-shot somehow. Though, mind you, I thought it was the most probable." '

Where I had to block the approach-shot somehow…

"Very early this morning," said Martin, clearing his throat "Jenny and I met Masters in a field near here. I asked him if he'd been at the prison during the night. Was he by any chance keeping an eye on my —welfare?"

That's right son. All night"

"Are you trying to tell me—" the words sounded wild, but Martin could not help using them—"that I've been a kind of focus for murder?"

"Uh-huh."

"But that's impossible!"

"Son," returned H.M., without any swelling of dignity, Tm the old man. I've got to believe," scowling ferociously, he rapped his knuckles against his bald head, "what this cokernut tells me is true. Even when Masters thought I was loopy and you won't believe it even now. I couldn't tell you, because— well, never mind the because. You were in a sweet whistlin' ring of danger. And you still are." H.M.'s tone changed. "Did you see who shoved you off that roof?"

"No."