From Austin "Rip" Ripleys Obituary:

"Austin Ripley was a syndicated newspaper columnist for the Chicago Tribune. He wrote a daily column call "Minute Mysteries," featuring Professor Fordney. The series found its way not only in more than 100 newspapers, but also in school classrooms where English teachers found that the short little mysteries aided "…in inferential thinking and reading for details… and productive to start each day …with a minute mystery that the class tries to solve." Ripley also conceived a new feature, "Photo Crime," starring detective Hannibal Cobb who solved hundreds of cases based on one or more photographs combined with a few sparse paragraphs that held the clues for the readers of Look Magazine to solve in every issue."

Ripley's catalogue was extensive and republished in many version, including as "Detectograms".