A few days ago I got a letter from my friend Taryn in the mail. She’s interning at a public library, cataloguing a collection of antebellum correspondence that includes the letters of two very close female friends. In the spirit of their friendship, she wrote a post-script in their letter-writing layout—as she puts it, the “nifty nineteenth century paper saving habit of filling up a page then turning the paper ninety degrees and writing across what you already wrote.”