Thanks Bob for the Heads-up.
Deterioration terra-cotta of is a national sleeping giant of a problem for
commercial buildings built in the late 19th century until the 1930's.
Water-related damage (corrosion) to metal anchoring can become hazardous
before it is detectable. (The age of the buildings -- 70 to 110 years -- is
probably warning enough that something may be going wrong inside those
beautiful facades.) The damage is usually due to breech of weather
resisting coverings and mortar joints, loss or deterioration of caulking, or
failure to replace lost pieces -- these things require thorough, periodic
observation and evaluation, and appropriate corrective measures. But an
effective inspection of the facade of a multistory commercial building on a
busy downtown street requires considerable investment in order to provide
access -- so it probably is rarely done often enough.
A beginners text on the nature of the problem is "Preservation Briefs 7, The
Preservation of Historical Glazed Architectural Terra-Cotta" by de Teel
Paterson Tiller is available from the Superintendent of Documents, U.S.
Contractors specialized in facade restoration are listed in the
January/February issue of Traditional Building (www.traditional-building.com