... room, he finds a man hanging from the centre of a high ceiling but there is no visible way he could have achieved it on his own.
The room consists of a flat concrete floor, flat grey walls, a flat ceiling with a short rope hanging from it, no window sills, no ledges, no beams to throw a rope over, no ladders, no furniture - just a very empty room really. He definitely can’t have jumped up there on his own).
After some careful consideration, Holmes decides that the man did manage to hang himself without the aid of anyone else, but how could he achieve it?. “Elementary My Dear Watson” was his response when asked “There really is only one way he, or anyone else, could achieve this”.
Just use the facts you have available and tell me how it was done