One of the early collections of classic detective stories was compiled by Willard Huntington Wright, better known by his nom-de-plume S. S. Van Dine. It comes with an excellent introduction in which Wright 'defines' what a detective story is -- as opposed to other kinds of popular fiction. He distinguishes four types of 'light' fiction vs. 'literary' fiction, but note that he doesn't mention the Comic Novel, which shouldn't surprise anyone: (a) Romance, (b) Adventure, (c) Mystery (including spy novels, crime, and horror), and (d) Detective Stories. By separating detection from mystery, defined as "wherein much of the dramatic suspense is produced by hidden forces that are not revealed until the denouement," he is making a point that is still under discussion today. "In one sense, to be sure, it [detection] is an offshoot of the [mystery]; but the relationship is far more distant than the average reader imagines. ... It is, in fact, a complicated and extended puzzle [or riddle] cast in fictional form."
This main object of his discussion is also the most controversial. In effect, he says that all attempts to provide atmosphere, characterization, and setting in a true detective story are irrelevant and distracting, that the most important element is the duel between the author and the reader in providing a solveable puzzle analogous to the crossword. Only the detective can show distinctiveness as a person, the more the better. What is also interesting is his historical background of detection up to the date of composition. It is quite comprehensive and well-written, even when many of the writers are all but forgotten these days. One will note that he mentions Christie -- including his famous condemnation of The Murder of Roger Ackroyd -- and others (including himself as Van Dine) who were later on to consolidate the Golden Age of Detection. The fact that he published this under his own name as an established art critic is an indication of how he considered this to be a serious study, along with his books Modern Painting, The Creative Will, What Nietzsche Taught, and Misinforming a Nation, listed in the front matter. There is also quite a bit of emphasis on the Continental, mostly French, detective novel (esp. Gaboriau, and somebody called Boisgobey, whom I have never heard of), which is a welcome thing to those of a chauvenistic mind apt to ignore anything not English or American. His main argument, quite right, is that Poe is the founder of detection as a distinct genre with its own rules, even though there are some detective elements in Herodotus, the Bible, The Arabian Nights, and other sources.
All aficionados of detective stories should have a copy of this book, along with Sayers's Omnibus of Crime and Queen's 101 Years' Entertainment. This is not a huge book -- 483 pages -- but is quite representative for 1927. The contents of the anthology are as follows (his approach was to present them chronologically):
Continental
One can cavil over particular stories by a given author, or even question why Copplestone and Phillpotts are incuded, even if it is pointless to do so (but I am thankful that the over-rated "Doomdorf Mystery" by Post was not selected, nor Poe's silly "Purloined Letter"). At the end of the Introduction he lists a number of cliches and other things that he recommends not be used in future detective stories, but his proviso accepts those that went before, that made them cliches in the first place. These are marked by me (* --xx) in the list above, including some he didn't mention, because many of the stories break his own rules, including the ones about 'excessive drama'. As Emerson put it, "A foolish consistency is the hobgoblin of small minds," so one does not have to agree with Wright's choices, just accept them.
If you read the Philo Vance novels, you would think that SSVD was an incredibile poseur. That was just the way he presented Vance as detective by his own rules of the game. In fact, Wright was a New York aristocrat (of the old school, not meaning new filthy rich like Trump or Steinbrenner or Bloomberg) and even if he lacked what we would call a sense of humor -- viz. the abominable "Gracie Allen Murder Case" -- he was a very cultivated man. I'm sure he was not a priss but could guzzle down illicit gin with the best of us.