Bookmark, small illustration at the top, text reads:
This card is meant to keep your place in this book. Please use it.
The true book-lover does not turn down leaves, nor bend them and does not leave a book lying open on its face, nor break its back in opening it.
I love my books. "A word to the wise is sufficient."
Found in "Nancy Drew Mystery Stories: The Hidden Staircase" by Carolyn Keene. Published by Grosset and Dunlap, 1930.
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