Page:Popular Science Monthly Volume 75.djvu/542

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538
THE POPULAR SCIENCE MONTHLY
ontology receive a meaning—upon any other hypothesis I am unable to see, in the slightest degree, what knowledge or signification we are to draw from them. Again, note. . . the singular likeness which obtains between the successive faunæ and floræ, whose remains are preserved in the rocks; you never find any great and enormous difference between them, unless you have reason to believe that there has also been a great lapse of time or a great change of conditions.

Just so did Chambers argue in his "Explanations," 1846:

Fifty years ago science possessed no facts regarding the origin of organic creatures upon earth. . . . Within that time, by researches in the crust of the earth, we have obtained a bold outline of the history of the globe. . . . It is shown on powerful evidence that during this time strata of various thicknesses were deposited in seas; . . . volcanic agency broke up the strata, etc. . . . The remains and traces of plants and animals found in the succession of strata show that while these operations were going on the earth gradually became the theatre of organic being, simple forms appearing first and more complicated afterwards. . . . This is a wonderful revelation to have come upon the men of our time, and one which the philosophers of the age of Newton could never have expected to be vouchsafed. The great fact established by it is that the organic creation, as we now see it, was not placed upon the earth at once:—it observed a progress.[1]. . . There is also the fact of an ascertained historical progress of plants and animals in the order of their organization. . . . In an arbitrary system we had surely no reason to expect mammals after reptiles; yet in this order they came.[2]

Thus the general fact of the gradual appearance of higher types in the course of geological time, and the existence of a broad parallelism between antiquity of strata and relative simplicity of the contained organic forms, was by this time thoroughly established and universally familiar. True it is, however, that the evidence from paleontology, when more minutely scrutinized, proved to be by no means so favorable to the development hypothesis. This was so far the case that the orthodox geologists were able, with some real plausibility, to turn this weapon against the evolutionists. One of the only two really serious reasons that could be advanced after 1840 for rejecting the hypothesis lay in the observation that the facts of stratigraphic geology, as then known, failed to exhibit, with any consistency, fulness or precision, the sequences that the hypothesis required. The principal fighting, between the time of the "Vestiges" and that of the "Origin," took place around this issue; and the battle-ground was well chosen for the conservatives. For the weakest side of the theory of development then was its paleontological side. But this continued to be its weakest side in the 1860's; and it is a side not wholly without weak points even at the present day, especially when to the theory of development is added the theory of natural selection.

The chief objections raised by the paleontologists were five in number. There was, first, the general difficulty about the "missing links" in the chain of past organisms. Secondly, there was the fact of the

  1. Op. cit., p. 21.
  2. Op. cit., p. 106.