Message #126233

[Lisa Wolfe]

CHAPTER VII.
THE EARTH STRUCK BY COMETS MANY TIMES.
IF the reader is satisfied, from my reasoning and the facts I have adduced, that the so-called Glacial Age really represents a collision of the earth with one of these wandering luminaries of space, the question can not but occur to him, Was this the first and only occasion, during all the thousands of millions of years that our planet has been revolving on its axis and circling around the sun, that such a catastrophe has occurred?

The answer must be in the negative.

We find that all through the rocky record of our globe the same phenomena which we have learned to recognize as peculiar to the Drift Age are, at distant intervals, repeated.

The long ages of the Palæozoic Time passed with few or no disturbances. The movements of the earth's crust oscillated at a rate not to exceed one foot in a century.[1] It was an age of peace. Then came a tremendous convulsion. It has been styled by the geologists "the epoch of the Appalachian revolution."

"Strata were upraised and flexed into great (olds, some of the folds a score or more of miles in span. Deep fissures were opened in the earth's crust," like the fiords or great rock-cracks which accompanied the Diluvial or Drift Age. "Rocks were consolidated; and over some parts sandstones and shales were crystallized into gneiss,

[1. Dana's "Text-Book," p. 150.]

{p. 432}