Thanks Barry, at least your copy of the card is better than my photo, of the print in the book, taken from the card!! Yes its a very evocative painting.
You're right, the painting must be somewhere, but lord knows where, maybe with some relative of JG I guess. Have had a bit of a look at that area, in terms of family trees, but its very unclear frankly.
Maybe someone will come up with the origin of the card, if nothing else.....
Am just trying to get the best quality image I can in order to make a poster type print.
Alex