Of course, Sharon. You are not in the least dense - this is an old English riddle form based on the spelling of the answer. It's like letter-Sudoku.
The answer is the "voice", telling you that its first (or second etc.) letter appears in the first word, but doesn't appear in the second.
So, its first letter is in the word "beech" but not in the word "pine". Actually, it's B, though it could have been C or H. The next one is L...
You have to sort out all the letters that it might be and fiddle around with them till the answer bites you in the bum. The words themselves are part of the message the riddle tries to convey.
Beech is a hardwood tree native to this area. When the place was prosperous with coal and iron and steel,
pine was introduced and grown to provide pit-props.
Coal is the natural fossil fuel,
mine the transient man-made means of exploiting it.
Seam is where nature put the coal,
wheel is the machine for raising it.
Iron is what they drew from the soil,
steel is what they made of it.
Nant is the old Welsh word for the stream that was always there,
river the English word for it when it was co-opted into the industrial process.
Always and
forever, which give the sixth (last) letter - well, they just reflect the thinking of the English poet who now lives here - in BLAINA.
That's the answer and is what is carved on top of the seventh stone. It was my attempt to offer respect for what the people feel they have lost and to suggest that, in the great scheme of things, the Industrial Revolution was just an interlude. Something to think of while you walk along the banks of the Ebbw Fach.
Here's another glimpse of Blaina, and some of the other Valley towns, written by local poet Idris Davies during the Depression and set to music by Pete Seeger.
http://www.youtube.com/watch?v=gP5gIDrNlrY