Geoscience Reference
In-Depth Information
sat up and really took notice. Although attempts had been made ear-
lier to describe the physiology and osteology of these streamlined
beasts, it was 1821 before clear descriptions of their structure were
published by Conybeare and Henry De la Beche in the Transactions of
the Geological Society. Conybeare followed this paper up with a
second published the following year in which he described and differ-
entiated four species of ichthyosaur based on differences in the mor-
phology of the teeth.
However, in the context of the present narrative, 1822 is also a
significant date, as he and William Phillips (1773-1828) published
their Geology of England and Wales as an accompaniment to their
geological map published a year earlier. This volume attempted to
place the geology they described in the context of that seen elsewhere
on the Continent. They were well placed to produce this work, as both
were geologists of considerable ability. Phillips was a founder member
of the Geological Society and a Fellow of the Royal Society and had
already published a volume and contributed to another, on the geology
of England and Wales. He had another valuable asset: he was a printer
and bookseller, so the cleric and typesetter had no difficulty finding a
publisher and distributor for their work. In their book Conybeare and
Phillips erected a hierarchy of orders: the granite was placed in the
Inferior, the bulk of the stratified successions were assigned to one of
three medial orders while the overlying unconsolidated sediments
were placed in their Superior order. Within the Medial order they
defined the Carboniferous: this term had been first suggested by
Richard Kirwan. In the type area in Britain three lithologies were
recognised: the Mountain Limestone was the oldest and comprised
flat highly fossiliferous bedded limestones; overlying this were the
Millstone Grits, a succession of coarse sandstones; and these were
topped off with the Coal Measures, a sequence of coal seams, sand-
stones and shales which were primary commodities that fuelled the
Industrial Revolution in Britain.
The term Carboniferous is now used globally. Until recently geo-
logists in North America recognised two Periods, the Mississippian
