ABSTRACT
The Saint John Baptistery at Florence, Italy, dates back to the XI century, it was built by and is property of the People of Florence. The Baptistery was built with deep and well-done foundations, a strong structure made up with a very good masonry, constituted by mortared hard stone pieces, and columns in granite; a marble revetment entirely covers its inner and outer faces, and the roof, too. In this first millennium of its life, it has been surviving to earthquakes, floods, wars, weathering, pollution and daily use by millions of people, being always in use. In this paper, we analyse its history through times in order to outline those principle and practices that has been allowing it to survive to Time and Men. A few milestone principles emerged by that: Intrinsic vulnerability, Induced vulnerability, Integrity, Authenticity, Maintenance, lasting of use and functions. We discuss these principles in the paper. The practices that have been permitting its conservation can be mainly ascribed to Opera del Duomo, a private board established in 1296 by the People of Florence with the mission to manage, maintain and conserve the Baptistery. During this millennium, arts and crafts knowledge and operative techniques has been handing down through traditions and a staff of skilled workers and technicians. Advice and support by external experts for specialist analysis and intervention guidelines complete the framework. In the last years, the Opera launched a conservation project based on these points: Anamnesis, Analysis, Diagnosis, Therapy and Maintenance. These actions and the results are here described and reported. The result is that Saint John Baptistery is in a good health and by ensuring monitoring and maintenance a long time ahead can be expected.
