Fritz Leiber 
Yesterday House [EPUB ebook] 
With linked Table of Contents

Jack Berry is told not to take his boat out into deep waters. But as any young man who has been told not to do a thing would, he does it anyway and discovers an island. When exploring the island he meets a beautiful young woman named Mary. She lives with her aunts on the island and has never been to the mainland. Mary is convinced that it’s the year 1933. Jack is sure she’s just been misinformed and plans to prove to her that it’s many years later than that. But is he right?