ten minutes to twelve
And , further , it must be possible to discover how he got out . '' The inspector smiled sourly , but made no reply . `` The circumstances , '' said Thorndyke , `` appear to have been these : The deceased seems to have been alone ; there is no trace of a second occupant of the room , and only one half-emptied tumbler on the table . He was sitting reading when apparently he noticed that the clock had stopped -- at ten minutes to twelve ; he laid his book , face downwards , on the table , and rose to wind the clock , and as he was winding it he met his death . '' `` By a stab dealt by a left-handed man , who crept up behind him on tiptoe , '' added the inspector . Thorndyke nodded . `` That would seem to be so , '' he said .