I was surprised to find that "thank-offering" is actually in Chambers' dictionary, and not at all surprised to find it means exactly what you'd expect.
The inscription is from Psalm 114:
Tremble, thou earth, at the presence of the Lord, at the presence of the God of Jacob;
Which turned the rock into a standing water, the flint into a fountain of waters.
GPS Coordinates:
51.46248, -2.60381
Location: High Kingsdown
