“We know that a dictaphone was supplied to Mr. Ackroyd. But no dictaphone has been found amongst his effects. So, if something was taken from the table⁠—why should not that something be the dictaphone? But there were certain difficulties in the way. The attention of everyone was, of course, focused on the murdered man. I think anyone could have gone to the table unnoticed by the other people in the room. But a dictaphone has a certain bulk⁠—it cannot be slipped casually into a pocket. There must have been a receptacle of some kind capable of holding it.

“You see where I am arriving? The figure of the murderer is taking shape. A person who was on the scene straightaway, but who might not have been if the crime had been discovered the following morning. A person carrying a receptacle into which the dictaphone might be fitted⁠—”

I interrupted. “But why remove the dictaphone? What was the point?”