"There Must Be a Mystery, and the Writer Must Not Deceive the Reader"

"The Plot of the Detective Story."
By George Barton (1866-1940).
First appearance: The Writer, April 1920.
Article (2 pages).
Online at Hathi Trust (HERE) and below.

Resources:
- FictionMags's thumbnail about George Barton: "Author,  journalist and historian. Born and died in Philadelphia, Pennsylvania."

- Barton pretty much occupied the transitional period between Holmes's Gaslight Era and the Golden Age of Detective Fiction, often collaborating with William J. Flynn at Argosy in the '20s; Barton's solo series character was Bromley Barnes, appearing in The Blue Book (1909-10) and Adventure (1911-12) (FictionMags data), most of the stories being collected in The Strange Adventures of Bromley Barnes (1918):
  (1) "The Case of the Mutilated Bibles," The Blue Book Magazine, November 1909
  (2) "The Patient in the State-Room," The Blue Book Magazine, December 1909
  (3) "The Case of the Empty Envelope," The Blue Book Magazine, January 1910
  (4) "The Case of the Stolen Parrot," The Blue Book Magazine, February 1910
  (5) "The Case of the Missing Man-of-War," The Blue Book Magazine, March 1910
  (6) "The Case of the Kidnaped Lady," The Blue Book Magazine, April 1910
  (7) "The Girl with the Frightened Eyes," The Blue Book Magazine, August 1910
  (8) "The Case of the Haunted Card-Room," The Blue Book Magazine, September 1910
  (9) "The Case of the Tattooed Sailor," The Blue Book Magazine, October 1910
  (10) "The Case of the Amsterdam Antiques," The Blue Book Magazine, November 1910
  (11) "The Case of the Stolen Specie," The Blue Book Magazine, December 1910
  (12) "The Case of the Strange Book Buyers," The Blue Book Magazine, January 1911
  (13) "The Adventure of the French Captain," Adventure, October 1911
  (14) "The Adventure of the Anonymous Cards," Adventure, November 1911
  (15) "The Adventure of the Leather Bag," Adventure, December 1911
  (16) "The Adventure of the Old Chess-Player," Adventure, January 1912.

The Goodreads description (HERE) shows how Barton leaned heavily toward espionage and international intrigue:
  "Bromley Barnes was created by George Barton and appeared in a number of short stories.
  "Barnes is a retired government agent who had spent thirty years 'in the confiden-
tial employment' of the U.S. government, working for the Secret Service, as 'Chief of the Special Agents of the Treasury Department,' and then for private missions for the State Department.
  "He's an older man who is still physically vigorous but who is quite capable of solving difficult crimes. He's helped by Cornelius Clancy, his valet and assistant."
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