Dublin wall

I work across from the Guinness brewery in Dublin, a cluster of massive 19th-century brick buildings with a maze of narrow cobblestone streets and alleys running in-between. It is perhaps not the cheeriest neighbourhood -- damp, pungent, with sunlight falling in thin shafts between the barrelhouses.

It does, however, have old cobblestone streets, wooden gates and horse carriages clopping by -- and, as we walked through the streets to lunch today, a teenager smoking a cigarette while riding a horse down the road. And, if I turn an unexpected corner, I come upon something like this picture.

If you can't read it, it says, in giant letters four metres up the wall, "STONE UPON STONE UPON FALLEN STONE," and then in the Irish language, "CLOCH OS CLON CLOICHE OS CLON CLOICHE LEATHA."

I'm not certain what it means, but I like that such a thing exists for its own sake.