He reported that all was quiet." "Then the assassin might have rung the bell at eleven," said Peter.
"Certainly not, for he could never have escaped immediately afterwards, without the policeman seeing him." "He might have got out by the back," suggested Juliet.
"My dear girl, what are you thinking of.

That wall round Lord Caranby's mansion blocks any exit at the back.

Anyone leaving the house must go up the lane or through that part at the bottom.

The policeman was near there shortly before eleven and saw no one leaving the house." "But, look here," said Mr.Octagon, who had been ruminating; "if, as the doctor says, death was instantaneous, how could your aunt have rung the bell ?" "Yes," added Juliet.

"And even had death not taken place at once, it could not have been more than a few minutes before eleven when the blow was struck.