You may find this article <http://www.nytimes.com/2014/12/16/science/the-echoes-of-hearts-long-silenced.html?module=Search&mabReward=relbias%3Ar%2C{%221%22%3A%22RI%3A9%22}> worth reading since it concerns the activities of ARSC member Patrick Feaster. It looks like he has found another area of archaeological sound to explore. Peter Hirsch