Sorry, asked the question and then had to travel for a couple of days. The science is great and doesn't in any way detract from the spectacle but the clouds I am talking about can be very high and the shadows are "HUGE" and of course its in Ireland. I think I know someone who will know, not a mudcatter, and if he does I'll post he answer in a future thread.Meanwhile
When the mists above my mountain rose
Two streams two lakes would stand unclothed
Pine forests standing tall and proud
A single headland clear of cloud
When I get to the bottom of line breaks it might read like a verse. Thanks all.