"A succession of Jurassic sediments is shown to have been metamorphosed in contact with a Tertiary microgranite. The metamorphic features of the three main lithological groups of the sediments are described and the conclusion is reached that in addition to simple thermal metamorphism, which is apparent in most of the rocks, the rocks nearest the microgranite have been permeated by aqueous fluids containing K 2 O, Na 2 O, MgO, FeO and Fe 2 O 3 ."