In one week during October of 1929, August Derleth wrote six Solar Pons stories: three of them in one day! However, a certain stock market crash occurred, causing Derleth some consternation. Check out when the stories were actually published:
The Adventure of the Viennese Musician – (1998)
The Adventure of the Limping Man (1929)
The Adventure of Gresham Old Place (1998)
The Adventure of the Muttering Man (1998)
The Adventure of the Black Cardinal (1930)
The Adventure of The Sotheby Salesman (1945)
So, two of the six appeared in magazines shortly after being written. Another was included in the first collection of Pons stories, sixteen years later. And three others did not appear (in The Final Adventures of Solar Pons) until sixty-nine years after being written! Which was twenty-seven years after Derleth died.