The state of his own mind was fast becoming a puzzle to him.
"More carving," he said to himself.

"That's the way these young idlers employ their long hours.

F.A.?
Those must be _his_ initials--Frank Aldersley.

Who carved the letters on the other plank?
Frank Aldersley, too ?" He turned the piece of wood in his hand nearer to the light, and looked lower down it.

More carving again, lower down! Under the initials F.A.
were two more letters--C.