It is always a joy when the reader gets to learn something (in a respectful way) about a chapter in history.  Mr. Mowers is an established historian of crime and we are treated to his original character, Mr. Mickleburgh who may possibly reflect an aspect of the author’s voice.  The Rondel Dagger of the title is the linchpin clue brought to this humble expert of ancient weapons by a young Sherlock Holmes. We enjoy his voice, which is markedly different from Watson, but equally good.  He simply sees things in a different way and traces of an avuncular admiration tinge this (sigh) short story.

1880 shows us the meeting of these two men, both masters at their field regardless of the disparity in ages. Mr. Mickleburgh is entrenched, respected, and largely invisible to the world but Holmes is already rising in what he calls his “financially precarious vocation.” The conversation between the…