BOOK VIII 
THE VOLCANOES OF TERTIARY TIME 
CHAPTER XXXIII 
Vast lapse of time between the close of the Palaeozoic and beginning of the Tertiary 
Volcanic Eruptions — Prolonged Volcanic Quiescence — Progress of Investigation 
among the Tertiary Volcanic Series of Britain. 
From the evidence which has been led in the foregoing chapters it is clear 
that during the later stages of the Palaeozoic period there was a gradual 
enfeeblement of volcanic vigour over the area of the British Isles. When 
the last puys of the Permian series became extinct a remarkable volcanic 
quiescence settled down on the region. This interval of rest lasted 
throughout the whole of the long succession of the Mesozoic ages. Though 
the geological record of this section of geological time is singularly complete 
in Britain, not a single vestige has yet been found in it of any contempor- 
aneous eruption. And what is true of this country is, on the whole, true 
of the entire European continent. With some trifling exceptions there were 
no volcanoes in Europe, so far as we know, during the enormous lapse of 
time between the last of the Palseozoic and the earliest of the Tertiary 
eruptions. 
When the geologist attempts to form an estimate of the chronological 
value of this interval of time he is soon lost in bewilderment over its 
obvious vastness, and the impossibility of discovering any standards of 
measurement by which to reckon its duration. On the one hand, he sees 
that it lasted long enough to admit of the gradual elaboration of many 
thousands of feet of various sedimentary deposits, which, from their remark- 
able diversities of character, were evidently accumulated, on the whole, with 
extreme slowness and amidst many geographical vicissitudes. On the other 
hand, he perceives that the interval sufficed to bring about an entire change 
in the fauna and flora of the globe. Indeed, the more he investigates the 
details of this biological transformation, the more he is impressed with the 
length of time that it must have required. For it is not merely one 
complete change, but a multifold succession of changes. The stratigraphical 
