A decent first novel, if a little long. Party mystery, part police procedural. I understand this author ranks up there with Agatha Christie and Dorothy L Sayers, but I hadn't heard of him before this.

The first section is policework, building the case against the shocked addressee of a cask containing coins and a body. In the second half, a defense is built, with another detective covering the same ground but from different angles. In both, the author lovingly describes pre-Great War London and France, going into a bit too much detail on the travel at times.

In addition to being a bit too wordy, the ending is very short. I can't say more without spoilers, but perhaps this was because the mystery genre was still evolving. Certainly some of the deductions were worthy of Sherlock Holmes.

Each year I try to read something from more than a century ago, and while wandering through Project Gutenberg I found this title. I didn't enjoy it as much as Doyle or Wells, but I'd like to try out another from this author - perhaps with his most famous protagonist, Inspector French.