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history. Lyell also realised that geological events could take place
reasonably quickly but smoothly - a realisation that found its most
forceful illustration at the 'Temple of Serapis', a ruined Roman com-
mercial edifice situated at Pozzuoli close to Naples, an engraving of
which Lyell chose to use as a frontispiece in many editions of his
Principles (Figure
8.5
). At Pozzuoli three columns of the entabulature
remain. Curious holes decorate the columns up to a height of twenty-
one feet above the present high water mark. Lyell visited the site in
early 1830 and deduced that the columns had become partially sub-
merged and the borings had been produced by the extant marine
bivalve Lithodomus in the recent past before the columns re-emerged
from the ocean. This marine transgressive-regressive sequence could
have been due to a lowering and rising of the land surface, or of the sea
level, or both. Whatever the cause, this dynamic movement did not
cause the remaining columns to fall and so was relatively smooth and
fast. This uniformitarianist view followed Hutton's and was in con-
trast to the views of some geologists such as AdamSedgwick who held
that many geological events were sudden and catastrophic.
Lyellwashugelysuccessful as ageologist, andwaswidelyknown,
both inEurope and inNorthAmerica. Onhis deathhewas accorded the
honour of being founda burial place inWestminsterAbbey.WhileLyell
was perhaps the public face of geology in Britain at this time, his ideas
were not universally accepted, particularly amongst some frequenting
the tight circles of academia and the Geological Society. Sedgwick did
not subscribe to all his views, nor did Buckland.
THE CONCEPT OF GEOLOGICAL TIME
As geologists recognised distinctive lithological units or groups of
units which could be distinguished from each other through examina-
tion of their fossil content, those same geologists began to realise that
each distinctive unit must represent some time in the past. Geological
time, as an abstract concept, began to unfold in the early decades of the
1800s, and while absolute timescales could not be attributed to the
emerging geological periods, the understanding that actual time was
