The inscription above by David Jones is in a mixture of Welsh and Latin. It reads
Cara Wallia derelicta....Literally 'Dear, abandoned Wales' (though David Jones himself once rendered it 'Poor buggered-up Wales'), 'on the feast day of Damaseus, Friday the Eleventh day of December, then was all Wales cast down' (the last bit of that is a line from the Elegy to Llywelyn the Last native Prince of Wales who was killed on that day). The inscription goes on to suggest a lineage for Llywelyn such as that claimed by Geoffrey of Monmouth for Arthur, but using the Latin of Virgil mixed with the Welsh of Gruffudd ap yr Ynad Coch:
The ineluctable hour of Troy has come
A leader's head, a dragon's head was upon him
Fair Llywelyn's head, a shock to the world
That an iron stake has pierced it.
(Llywelyn's body was buried at Abbey Cwm Hir in Wales but his head was impaled on London Bridge.)
And then, still echoing the Elegy from Llywelyn's bard:
'There is no counsel, no closure, no opening' (this running up the side of the inscription).
So here, on the 'first day after ten' of December, this is in memory of that winter - ab hieme - 1282.