102 Minutes (Abridged)

Many geologists have an equivocal attitude to fluid movements within the crust and the associated changes in the chemical and physical properties of crustal rocks. The controversies earlier this centuary between the "soaks" and the "pontiffs" memorably summarised by H. H. Read (1957) in The Granite Controversy have largely been resolved. Few would now advocate the formation of large granitic bodies by in situ transformation of pre-existing crust as the result of the passage of ichors without the…