Crossing the Border

I'm heading back to Scotland tomorrow, on the train. As ever, I think of crossing the border and some of the turns of phrase in this. from my favourite poet, McCaig:

Crossing the Border
(Rings on a Tree, 1968)

I sit with my back to the engine, watching
the landscape pouring away out of my eyes.
I think I know where I'm going and have
some choice in the matter.

I think, too, that this was a country
of bog-trotters, moss-troopers,
fired ricks and roof-trees in the black night — glinting
on tossed horns and red blades.
I think of lives
bubbling into the harsh grass.

What difference now?
I sit with my back to the future, watching
time pouring away into the past. I sit, being helplessly
lugged backwards
through the Debatable Lands of history, listening
to the execrations, the scattered cries, the
falling of roof-trees
in the lamentable dark.