In Hitchiker’s Guide, readers are told to always bring along a towel, because it can be so useful. In Left handed Booksellers of London, it’s a book you should always bring, so you never get bored. This got me thinking about whether there are other books that mention an item you should never be without, and what it might be. Can anyone pitch in with some mentions? I want to collect a list of wise things to always have with me, and the books they came from. Thanks in advance
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by bothnatureandnurture