PREFACE.


The object of this book is to provide the beginner in the study of the
earth's history with a general account of those actions which can be
readily understood and which will afford him clear understandings as
to the nature of the processes which have made this and other
celestial spheres. It has been the writer's purpose to select those
series of facts which serve to show the continuous operations of
energy, so that the reader might be helped to a truer conception of
the nature of this sphere than he can obtain from ordinary text-books.

In the usual method of presenting the elements of the earth's history
the facts are set forth in a manner which leads the student to
conceive that history as in a way completed. The natural prepossession
to the effect that the visible universe represents something done,
rather than something endlessly doing, is thus re-enforced, with the
result that one may fail to gain the largest and most educative
impression which physical science can afford him in the sense of the
swift and unending procession of events.

It is well known to all who are acquainted with the history of geology
that the static conception of the earth--the idea that its existing
condition is the finished product of forces no longer in action--led
to prejudices which have long retarded, and indeed still retard, the
progress of that science. This fact indicates that at the outset of a
student's work in this field he should be guarded against such
misconceptions. The only way to attain the end is by bringing to the
understanding of the beginner a clear idea of successions of events