GEOLOGY 
and Silurian rocks, which extended far and wide, and far beyond the 
limits of the county. The rocks forming this great floor are very hard 
and durable, taken as a whole. It was upon this nearly-level founda- 
tion that (after many changes had arisen) the Upper Old Red Sandstone 
and the Carboniferous Rocks were spread out, layer upon layer, to a 
thickness of many thousands of feet. The general relation of the lower 
portion of these rocks to the floor beneath at the stage under considera- 
tion is illustrated by fig. 1. In this the general lie of the old rocks 
is shown, and the relationship of the granite masses, as well as the 
hypothetical remains of the Caledonian Old Red, to the older sediments 
is also indicated in a diagramatic way. As a whole the Carboniferous 
Rocks are less durable than the rocks beneath. The former may waste, 
say, five feet in a given time, during which the latter may waste 
three. 
Now it is important to remember that after the close of the 
Carboniferous Period the whole pile, floor and all, was folded and 
fractured. A great centre of upfolding coincided with the present Lake 
district; and the upward movement over that centre was carried to 
such an extent that the old floor was there lifted to a higher level than 
the top of the Carboniferous Rocks in the district to the east. More- 
over the great zone of fracture and disturbance, known collectively as the 
Pennine Faults, already in existence as a zone of weakness, gave way 
once again, and the rocks on the north-east side of this zone were 
elevated to a higher position than those on the side opposite. While 
these movements were in progress denudation continually attacked the 
rocks on the higher ground, so that after an exposure for a great length 
of time the whole of the Carboniferous Rocks were worn away from 
the summit of the dome, and much of them from the other zone of 
elevation on the east side of the Pennine Faults. — 
It was upon an irregular surface formed out of the associated 
Cambrian, Ordovician, Silurian, Devonian and Carboniferous strata, 
all more or less disturbed, that the New Red Rocks in their turn were 
afterwards spread out. Fig. 2 may help to make this relationship 
more clear, especially if it be studied in connection with fig. 1. 
The section is arranged to show that at least the higher members of the 
New Red formerly extended right over what is now the Lake district, 
as well as across the Pennine Faults, on to the area which now forms 
the Cross Fell uplands. 
To understand what ensued it may be as well if we agree to refer 
to the two floors just mentioned by definite names. The older one we 
may call ‘the First Plain ’—for although in minor details the surface 
was uneven, yet regarded broadly its nature was more or less as much 
a plain as most submarine surfaces around the British Isles are now. For 
the surface, more or less irregular, upon which the New Red was 
deposited, we may also employ the term ‘ plain,’ and refer to the floor 
below the New Red as ‘ the Second Plain.’ 
After the close of the period which commenced with the formation 
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