As with some of the other facts with which we have had to deal in
previous chapters, a correct understanding of the questions involved
can best be obtained by examining the history of the development of the
science.
The first man with whom we need to concern ourselves is A.G. Werner, a
teacher of mineralogy in the University of Freiberg, Germany. For three
hundred years his ancestors had been connected with mining work, and he,
though possessing little general education, knew about all that was then
known regarding mineralogy and petrology. He wrote no books; but by his
enthusiastic teaching he gathered as students and sent out as
evangelists hundreds of devoted young scientists who rapidly spread his
theories through all the countries of Europe.
"Unfortunately," says Zittel, "Werner's field observations were limited
to a small district, the Erz Mountains and the neighboring parts of
Saxony and Bohemia. And his chronological scheme of formations was
founded on the mode of occurrence of the rocks within these narrow
confines."[34]
[Footnote 34: "History of Geology," p. 59.]
Werner had found the granites, limestones, sandstones, schists, etc.,
occurring in a certain relative order in his native country; and he drew
the very remarkable conclusion that this was the _normal_ order in which
these various rocks would invariably be found in all parts of the world,
on the theory that this was the order in which these different rocks had
been formed in the beginning, great layers of these different rocks
having originally been spread completely around the globe one outside
another like the coats of an onion. With this as a major premise, it is
not surprising that he and his enthusiastic disciples "were as certain
of the origin and sequence of the rocks as if they had been present at
the formation of the earth's crust."[35]
[Footnote 35: A. Geikie, "Founders of Geology," p. 112.]
The amusement with which this onion-coat theory is now regarded is
hardly appropriate in view of its universal vogue among geologists about
the beginning of the nineteenth century, and in view of the further fact
that a very similar and only slightly modified substitute theory has
been universally taught for three-quarters of a century _and still
prevails_. The modern form of the theory substitutes onion-coats of
fossiliferous rocks for onion-coats of mineral and lithological
characters; and a brief consideration of this theory is now in order.
About the time that various geologists here and there were finding rocks
in positions that could not be explained in terms of Werner's theory,
William Smith (1769-1839) in England and the great Baron Cuvier
(1769-1832) in France found characteristic fossils occurring in various
strata; and under their teachings it was not long before the fossils
were considered the best guide in determining the relative sequence of
the rocks. The familiar idea of world-enveloping strata as representing
successive ages was not discarded; but instead of Werner's successive
ages of limestone making, sandstone making, etc., these new
investigators taught that there were successive ages of invertebrates,
fishes, reptiles, and mammals, these creatures having registered their
existence in rocky strata which thus by hypothesis completely encircled
the globe one outside another.
It is true that early in the nineteenth century Sir Charles Lyell and
others tried to disclaim this absurd and unscientific inheritance from
Werner's onion-coats; but modern geology has never yet got rid of its
essential and its chief characteristic idea, for all our text-books
still speak of various successive ages _when only certain types of life
prevailed all over the globe_. Hence it is that Herbert Spencer
caustically remarks: "Though the onion-coat hypothesis is dead, its
spirit is traceable, under a transcendental form, even in the
conclusions of its antagonists."[36] Hence it is that Whewell, in his
"History of the Inductive Sciences," refuses to acknowledge that in
geology any real advance has yet been made toward a stable science like
those of astronomy, physics, and chemistry. "We hardly know," he says,
"whether the progress is begun. The history of physical astronomy almost
commences with Newton, and few persons will venture to assert that the
Newton of geology has yet appeared."[37] Hence it is that T.H. Huxley
declares, "In the present condition of our knowledge and of _our
methods_, one verdict,--'_not proven and not provable'--must be recorded
against all grand hypotheses of the palæontologist respecting the
general succession of life on the globe."[38] And hence it is that Sir
Henry H. Howorth, a member of the British House of Commons and the
author of three exhaustive works on the Glacial theory, declares, "It is
a singular and notable fact, that while most other branches of science
have emancipated themselves from the trammels of metaphysical reasoning,
_the science of geology still remains imprisoned in a priori_
theories."[39]
[Footnote 36: "Illustr. of Univ. Prog.," p. 343.]
[Footnote 37: Vol. II, p.580.]
[Footnote 38: "Discourses," pp. 279-288.]
[Footnote 39: "The Glacial Nightmare," Preface, vii.]
And thus the matter remains even to-day, in this second decade of the
twentieth century. _Geology has never yet been regenerated_, as have all
the other sciences, by being delivered from the caprice of subjective
speculations and _a priori_ theories and being placed on the secure
basis of objective and demonstrable fact, in accordance with the
principles of that inductive method of investigation which was
instituted by Bacon and which has become so far universal in the other
sciences that it is everywhere known as the scientific method. In
accordance with this method, theories in all the other sciences are
always kept well subordinated to facts; and whenever unequivocal facts
are found manifestly contradicting a theory no matter how venerable, the
theory must go to make way for the facts. In other words, the
theoretical parts of the various other sciences are always kept revised
from time to time, to keep them in line with the new discoveries that
have been made. There has been no lack of astonishing discoveries of new
facts in geology during the past half century or so, while all the other
sciences have been making such astonishing progress. _But for over
seventy five years geology has not made a single advance movement in its
theoretical aspects_; indeed, in all its important general principles it
has scarcely changed in a hundred years. I shall leave it to the reader
to judge whether this is a case of almost miraculous perfection from the
beginning, or of arrested development.