Another of my favorites was "The Thinking Machine" series by Jacques Futrelle. (The Thinking Machine.)
"This irascible genius, this diminutive egghead scientist, known to the world as “The Thinking Machine,” is no less than the newly rediscovered literary link between Sherlock Holmes and Nero Wolfe: Professor Augustus S. F. X. Van Dusen, who—with only the power of ratiocination—unravels problems of outrageous criminous activity in dazzlingly impossible settings. He can escape from the inescapable death-row “Cell 13.” He can fathom why the young woman chopped off her own finger. He can solve the anomaly of the phone that could not speak. These twenty-three Edwardian-era adventures prove (as The Thinking Machine reiterates) that “two and two make four, not sometimes, but all the time.”"
I was later amazed to learn that Jacques Futrelle was one of the passengers who went down on the Titanic. Returning from Europe aboard the RMS Titanic, Futrelle, a first-class passenger, refused to board a lifeboat, insisting his wife, Lily, do so instead, to the point of forcing her in. She remembered the last she saw of him: he was smoking a cigarette on deck with John Jacob Astor IV. He perished in the Atlantic and his body was never found.
10 years old is also a good time to read everything written by Jules Verne.