Both the Broc Hill and the Walton-on-the-Hill pieces function as figure of '8' Analemmatic sundials, and developed out of an original brief by Berskwich Millennium Sculpture Group requesting seating at opposite ends of a 3 mile footpath.
They are built from Limestone, steel and concrete. The biggest stone, packed with fossils and used to mark midday, weighs over 3 tons and had to be sited a mile from the nearest road.
The maths needed to was kindly donated by M Gaylard/HartRAO in South Africa whom I've only met on the Internet yet they provided great support in getting the project going.
The major sponsors were:
Abbey Polymers Ltd
Awards for All
Berkswich Parish Council
Landon Engineering (steel plates)
Stafford College
S.C.C. Arts Grant Scheme
S.C.C. Countryside
Tarmac Central (Limestone and transport from Calden Lowe)
Wardel Armstrong (Technical advice and setting out)