"Here Was a Community Almost As Large As That of a Small Town and With No Clue to Go Upon"

"The Umania Affair."
By Orme Agnus (John C. Higginbotham, 1866-1919).
First appearance: The Royal Magazine, February 1902.
Short short story (6 pages, 3 illos).
Online at Hathi Trust (HERE).

"But, Monsieur, you are wrong, the doctor is wrong, my poor dear father has been murdered."

The "great detective" De Warr is recuperating from an attack of influenza by taking what begins as a restful transatlantic cruise, when a fellow passenger collapses and dies in plain sight of a dozen witnesses, with none of them being closer than six feet; the ship's doctor at first believes it to be a heart condition, but the victim's daughter knows better, and a post-mortem reveals the fatal wound was caused by a bullet, fired from a gun that absolutely nobody saw or even heard . . .

The usual suspects:
~ Captain Sibley, in command of the Umania:
  "The Atlantic is the finest tonic in the world, I always maintain."
~ De Warr (no other name):
  "I have been a great fool in this matter. I deserve to be kicked. I felt so satisfied with myself that I forgot."
~ Monsieur Monteil:
  "De Warr delicately hinted his surprise that so ardent a patriot could tear himself away from his country, but to that Monseiur returned no answer, but changed the subject."
~ Mademoiselle Monteil:
  "You have sent for me to tell me my father was murdered, is it not so?"
~ Selwyn, the ship's doctor:
  "Here is the bullet. It was hollow and contained prussic-acid . . ."
~ Herr Arndt:
  ". . . an old, white-haired German, bent as if with rheumatism . . ."

Comment: Although an English detective (and, to be frank, not really a "great" one),
De Warr shares—in fact, anticipates—mannerisms belonging to a certain little Belgian "heavesdropper"; and the murder weapon prefigures one used in a Dr. Thorndyke
story eight years later.

Resources:

- The most we could find about our author were this notation about one of his novels, which confirms us in thinking that his preferences ran to mainstream rather than detective fiction:
  "Although born in Cheshire, Higginbotham lived throughout his life at Wareham in Dorset, where he was a schoolteacher. He specialized in the depictions of rural life that were so popular at the turn of the century.
Love in Our Village (1900) describes the idyllic side of village life seen
through the eyes of a convalescent from London. It owes much to the
works of Thomas Hardy (1840-1928), but a more ebullient tone predom-inates. - Kemp, Mitchell and Trotter, [The Oxford Companion to] Edward-
ian Fiction [2002], page 3."
. . . and this bibliography page:
  "Born in Cheshire. At the age of 18, he moved to Wareham, Dorset, where he worked as a school teacher until his death. A disciple of Thomas Hardy, but not a pessimist. Has been compared in turn, and not without reason, to George Eliot, Hardy and Barrie."