Early that morning a peasant had met a cart containing several people and some very bulky boxes driving rapidly in the direction of Reading, but there all traces of the fugitives disappeared, and even Holmes’ ingenuity failed ever to discover the least clue as to their whereabouts.
There are no more uses of "ingenuity" in the book.
Show samples from other sources
He exercised great ingenuity in making excuses for missing class.
It will take more than ingenuity to clean this up. We’re going to have to admit our mistake.