We had visited Chedworth Villa, and we were proudly shown the mosaic, which had only recently been uncovered.

A sixth former found that it raised several topics for conversation.

♦  First, what about the word mosaic itself? Not a Latin word, surely?

No.  The word dates from the Middle Ages: a generic term for any design or picture made by the assemblage and cementing together of small pieces of hard material.

The Roman name for the mosaic flooring that most students are familiar with was a pavimentum tessellatum—where the picture or design was made of small cubic pieces (tesserae).

But a pavement might be sectile: composed of tiles cut to geometric shapes.

Or it could be vermiculatum—made of marble pieces cut to the shapes demanded by the picture, and creating a vividly realistic effect.

♦  Then there was this Roman desire for permanence. A tessellated floor like the one at Chedworth was created to last for centuries or millennia, no matter how many feet passed across it; and indeed the passing of feet would keep its colours fresh.

This insistence on durability was something that reminded our student of her visit the year before to the Pont du Gard at Nîmes. She remembered the jutting-out stones on that giant aqueduct, left to aid the maintenance men build their scaffolding in the years, centuries and millennia to come.

“Did they think these things would last for ever?” she asked.

“Yes,” replied a colleague.

♦   This raised the topic of the monumentum, a word which Horace made clear could apply to any work of art or skill. And at this point we advised the student to look up the word moneo in Lewis and Short. The verb can mean: remind, bring to recollection, admonish, advise, warn, teach, instruct, tell, inform, point out, announce, foretell.

So those are the things that a monumentum can do! It was my turn to be reminded of something: the remark of a geography colleague who had also visited the Pont du Gard. He said it was the most impudent building he had ever seen.