Charles Neville Buck 
Key to Yesterday [EPUB ebook] 

Excerpt: "A young painter has dedicated himself to his art and left out all other pursuits and diversions. At last he admits to his closest friend the reason for his quiet life: he cannot recall anything from more than seven years before. When he falls deeply in love with the neighbor girl, he is spurred to reinvestigate his past based on a new clue. Neither could dream of the results."