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many of the second rank in 70 years. In dramatic art nothing 
in so short a time can be shown to equal the performances of the 
three tragedians whose names J have dealt with this evening. 
ENGLAND DURING GEOLOGICAL AGES. 
By J. MONCKMAN, D.Sc., February 19th, 1884. 
Where was the land? This question necessitates the ex- 
planation of the methods used to tell the ages of hills. If we 
find that while some beds are raised with the mountain and lie 
upon it, we conclude that the mountain cannot be older than the 
beds raised, and if we find that other strata lie level at the foot 
of the hill, the mountain must have been raised to its present 
position before the horizontal beds were deposited. In the Alps 
we see the pliocene level, but the older beds bent into the shape 
of the hills; hence we say that the Alps have been partly raised 
since the eocene and before the pliocene ages. Sometimes -we 
find the same thing with the addition that the beds change in 
composition. The limestone is thick and pure in Derbyshire, 
less so in Lancashire and Yorkshire, and becoming mixed with 
shore dirt northwards and southwards. Not only so, but at one 
point when a pit was sunk for coal, instead of coal there was 
found a hard slate rock, and on the surface of it rounded pebbles 
revealing the action of water, probably sea water, and showing it 
to have been the old shore. When we apply this to the Cambrian 
rocks we are uncertain. I do not know that there is information 
enough at hand to enable us to decide, but yet we may get some 
idea. We find that the beds that come to the surface in North 
Wales, Shropshire, Leicester, Bohemia, and also Skiddaw, Nor- 
way and Sweden, and in America, New York State and Valley of 
Mississippi, there appears to be a tendency of sandstone and 
shale north, and limestone south, as though the land were 
northward. There are but two points of land surface in Britain 
now exposed which could have been land at that time. The Silurian 
period was one of great upheavals, when the very foundations 
of the land rocked and shook by reason of the mighty forces 
striving to burst forth in living streams to the surface of the 
earth. Volcanoes on land belched forth their showers of ashes 
and stones, darkening the face of the sun, whilst sheets of fiery 
lava flowed down the sides of the mountains. Nor was the sea at 
rest. From unseen vents enormous quantities of volcanic materials 
issued, forming layer after layer on the bottom of the ocean, over 
which the steady deposition of mud and sand continued as usual. 
Could we have taken post on the top of venerable Skiddaw, we 
