VI 
THE ANCIENT VOLCANOES OF GREAT BRITAIN 
BOOK VIII 
THE 'VOLCANOES OF TEETIAEY TIME 
CHAPTEE XXXIII 
PAGE 
Vast lapse of time between the close of the Palseozoic and beginning of the Tertiary 
Volcanic Eruptions — Prolonged Volcanic Quiescence — Progress oi Investigation 
among the Tertiary Volcanic Series of Britain 107 
CHAPTEE XXXIV 
The System of Dykes in the Tertiary Volcanic Series 
Geographical Distribution— Two Types of Protrusion— Nature of component Rocks— Hade 
— Breadth — Interruptions of Lateral Continuity — Length — Persistence of Mineral 
Characters 
CHAPTEE XXXV 
The System of Dykes — continued 
Direction — Termination upward — Known vertical extension —Evidence as to the move- 
ment of the Molten Rock in the Fissures— Branches and Veins— Connection of Dykes 
with Intrusive Sheets — Intersection of Dykes — Dykes of more than one infilling 
— Contact metamorphism of the Dykes — Relation of the Dykes to the Geological 
Structure of the Districts which they traverse— Data for estimating the Geological 
Age of the Dykes — Origin and History of the Dykes ..... 
CHAPTEE XXXVI 
The Plateaux 
Nature and Arrangement of the Rocks : 1. Lavas. — Basalts, Dolerites, Andesites — Struc- 
ture of the Lavas in the Field — 2. Fragmental Rocks. — Agglomerates, Con- 
glomerates, and Breccias — Tuffs and their accompaniments .... 
CHAPTEE XXXVII 
The Several Basalt-Plateaux and their Geological History — Antrim, Mull, 
Morven and Ardnamurchan . • • • ... 
199 
CHAPTEE XXXVIII 
The Basalt-Plateau 
canic Period 
of the Parish of Small Isles — Rivers of the Vol- 
215 
