CHAPTER XU. 
The two Aspects in which Matter can be viewed; Space and Time. 
— Geological History of the Earlier Periods. — The Cambrian Sys- 
tem. — Its Annelids. — The Silurian System. — Its Corals, Encrin- 
ites, Molluscs, and Trilobites. —Its Fish. — These of a high Order, 
and called into Existence apparently by Myriads. — Opening Scene 
in the History of the Old Red Sandstone a Scene of Tempest. — 
Represented by the Great Conglomerate. — Red a prevailing Color 
among the Ancient Rocks contained in this Deposit. — Amazing 
Abundance of Animal Life. — Exemplified by a Scene in the Her- 
ring Fishery. — Platform of Death. — Probable Cause of the Catas- 
trophe which rendered it such. 
“THERE are only two different aspects,” says Dr. Thomas 
Brown, ‘‘ in which matter can be viewed. We may consider 
it simply as it exists in space, or as it exists in time. As it 
exists in space we inquire into its composition, or, in other 
words, endeavor to discover what are the elementary bodies 
that coexist in the space which it occupies; as it exists in 
time, we inquire into its susceptibilities or its powers, or, in 
other words, endeavor to trace all the various changes which 
have already passed over it, or of which it may yet become 
the subject.” | 
Hitherto I have very much restricted myself to the consid- 
eration of the Old Red Sandstone as it exists in space — to 
the consideration of it as we now find it. I shall now attempt 
presenting it to the reader as it existed in tzme— during the 
succeeding periods of its formation, and when its existences 
lived and moved as the denizens of primeval oceans. It is 
one thing to describe the appearance of a forsaken and des- 
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