Sherlock Holmes and the Man In Concrete

Trawling fishermen are surprised to find tangled in their nets a concrete block with a man's head protruding from it. Sherlock Holmes and Dr. Watson investigate. Sherlock Holmes samples the concrete block, which is made of hydraulic cement, and this plus curious pittings on the block's upper surface lead them to the killer, who is tried, convicted and hanged, without incident..
This is the shortest of my six Sherlock Holmes works, having been written for a contest specifying no more than 2500 words. It won a contest prize.. Written in the style of Sir Arthur, and set in Victorian England, if you like reading about Sherlock Holmes, you will like this story.