You keep your eye on your iPhone nor do you leave your car running when you dash into a Starbuck's to order coffee. In medieval times the value of a book was nearer that of your car than your smart phone. There were three main ways to protect a book: chain, chest or curse.
Chain, chest, curse: Combating Book Theft in Medieval Times is an amusing overview of these three methods.
We still lock valuables in a safe and chain our bikes, but curses are no longer deemed an effective safeguard.
Ernster, the Virtual Library Cat
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