Imagine how thrilling and appalling it must be, all at once, for a gigging jazzman to learn that a lost John Coltrane album is due to be released on June 29.

Remember your Jack Kerouac, whose Sal Paradise recalls some young bop musicians urging George Shearing to step out of the audience and play at a Chicago club in “On the Road”:

He played innumerable choruses with amazing chords that mounted higher and higher until the sweat splashed all over the piano and everybody listened in awe and fright. They led him off the stand after an hour. He went back to his dark corner, old God Shearing, and the boys said, “There ain’t nothin’ left after that.”

But the slender leader frowned. “Let’s blow anyway.”

Something would come of it yet. There’s always more, a little further — it never ends.