Pitstone font : Understanding the environment

Much of the decay affecting the font is being driven by dampness. Where is this dampness coming from?  This image shows severe pitting in the wall plaster immediately adjacent to the font caused  by rising damp and salts.  The moisture being evaporated into the church from areas like this will condense on all the fittings in the church including the font...

Is it worthwhile curing  the immediate problems of the font unless this cause of an unsatisfactory wider environment is not first addressed?

Achieving the best balance between environmental management and physical repair is rarely simple .  It is often much easier to ignore the wider problems and concentrate on immediate details. An outside view, from an experienced eye, can often be of great value.