Q: I suspect you’ve already heard this from other WNYC listeners: Pat might want to recheck the definition of “palimpsest” that she gave during her January appearance on the Leonard Lopate Show.

A: Yes, the definition of “palimpsest” that Pat mentioned on the air isn’t the one found in standard dictionaries, though some writers have used the term figuratively since the 19th century in the way she did.

Pat was referring to crossed (or cross) writing, an old practice in which a letter writer who was poor or frugal would fill a page of paper with writing, then turn it sideways and fill the page again with text running perpendicularly to the original.

The term “palimpsest,” as you point out, refers to a very different way of conserving writing material.

In bygone days, when documents were written on sturdy stuff like parchment or vellum, the writing could be at least partially scraped or rubbed away so the material could be reused. Documents made of more fragile papyrus were sometimes washed and used again too.

Such a recycled document is called a “palimpsest,” and sometimes the ghost of the old writing can be seen beneath the new.

Although writing material has been recycled since classical times, the term “palimpsest” didn’t show up in English until the early 19th century, according to citations in the Oxford English Dictionary.

A bit later in the 19th century, the term was extended to various figurative uses, including multilayered records. The OED doesn’t specifically mention cross-written letters in its citations for “palimpsest,” but the usage can be found in 19th-century texts.

For example, Sir Philip Grey Egerton, an English paleontologist, uses the term in this sense in an 1869 family history that refers to “letters themselves converted into palimpsests by cross writing.”

This practice was extremely common among writers who wanted to save on postage, paper, or both. The poet Keats and the novelist Jane Austen, to mention two examples, were known to have written letters like this.

Such letters were of course a real challenge to read! Charles Dodgson, otherwise known as Lewis Carroll, invented an appropriate proverb in a booklet he wrote on letter-writing in 1888: “Cross-writing makes cross reading.”

True, the intention with the ancient palimpsests was to obscure the old writing, while 19th-century letter writers intended that both layers of writing would be legible.

Here are the OED’s three definitions of “palimpsest” (from the Greek for “scraped again”):

(1) “Paper, parchment, or other writing material designed to be reusable after any writing on it has been erased.” This meaning is now obsolete.

(2) “A parchment or other writing surface on which the original text has been effaced or partially erased, and then overwritten by another; a manuscript in which later writing has been superimposed on earlier (effaced) writing.”

(3) “In extended use: a thing likened to such a writing surface, esp. in having been reused or altered while still retaining traces of its earlier form; a multilayered record.”

We’ll end with the OED’s earliest extended use of “palimpsest,” from an essay by Thomas de Quincy in the June, 1845, issue of Blackwood’s Edinburgh Magazine: “What else than a natural and mighty palimpsest is the human brain?”

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