Not actually books but blocks with the name of each book of the Bible on it.
The cover of each book has the name of the book, who wrote it, whats it's about, and how many chapters it has. The back has a key verse from that book.
When the Sabbath day was a day of quiet, introspective activity esp. for children these toys were to help teach the child while hopefully encouraging a little quiet fun at the same time. You could arrange the books in order or try to get someone to guess which book a verse came from and other fun details. Those Victorians! They thought of everything it seems.