Wise Words (V): Enclose It

«Sec. 3. How to go on with a Letter
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My eighth Rule. When you say, in your letter, "I enclose cheque for L5", or "I enclose John's letter for you to see", leave off writing for a moment—go and get the document referred to—and put it into the envelope. Otherwise, you are pretty certain to find it lying about, after the Post has gone!»

Lewis Carrol, Eight or Nine Wise Words about Letter-Writing