The Wind in the Willows
Why does the Otter suddenly disappear? What is the second animal etiquette that Mole recalls?
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Chapter please?
From the text:
The Rat hummed a tune, and the Mole recollected that animal-etiquette forbade any sort of comment on the sudden disappearance of one's friends at any moment, for any reason or no reason whatever.
The Wind in the Willows