Martin John Callanan, Data Soliloquies, Argentea Gallery, 2017 Martin John Callanan, Data Soliloquies, Argentea Gallery news Home News Data Soliloquies - Argentea Gallery Posted 2017/04/11 12:08 Martin John Callanan is showing in Data Soliloquies at Argentea Gallery, 28 St Paul’s Square, Birmingham B3 1RB, from 11 May - 10 June 2017. See .