Geological Magazine, Volume 1

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Henry Woodward
Cambridge University Press, 1864
 

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Page 233 - I will conclude by expressing to you my thanks for the honour you have done me in asking me to preside over this Meeting. I have...
Page 232 - Yet the whole body of monuments which we are endeavouring to decipher appears more defective than before. For my own part I agree with Mr. Darwin in considering them as a mere fraction of those which have once existed, while no approach to a perfect series was ever formed originally, it having never been part of the plan of nature to leave a complete record of all her works and operations for the enlightenment of rational beings who might study them in after ages.
Page 233 - Europe, or those to which the term primordial had been rashly assigned. In the first place, the newest part of this great crystalline series is unconformable to the ancient fossiliferous or so-called primordial rocks which overlie it ; so that it must have undergone disturbing movements before the latter or primordial set were formed. Then again, the older half of the Laurentian series is unconformable to the newer portion of the same. It is in this lowest and most ancient system of crystalline strata...
Page 232 - On the first point it is worthy of remark that, although a belief in sudden and general convulsions has been losing ground, as also the doctrine of abrupt transitions from one set of species of animals and plants to another of a very different type, yet the whole series of the records which have been handed down to us are now more than ever regarded as fragmentary. They ought to be looked upon as more perfect, because numerous gaps have been filled up, and in the formations newly intercalated in...
Page 232 - In reference to the other great question, or the earliest date of vital phenomena on this planet, the late discoveries in Canada have at least demonstrated that certain theories founded in Europe on mere negative evidence were altogether delusive. In the course of a geological survey, carried on under the able direction of Sir William E. Logan, it has been shown that northward of the river St. Lawrence there is a vast series of stratified and crystalline rocks of gneiss, mica-schist, quartzite, and...
Page 233 - It is in this lowest and most ancient system of crystalline strata that a limestone, about a thousand feet thick, has been observed, containing organic remains. These fossils have been examined by Dr. Dawson, of Montreal, and he has detected in them, by aid of the microscope, the distinct structure of a large species of Rhizopod. Fine specimens of this fossil, called Eozoon Canariense, have been brought to bath by Sir William Logan, to be exhibited to the members of the Association.
Page 91 - Old lied ; thirdly, conformable strata, consisting of conglomerates and foot-bearing and other sandstones appertaining to the higher members of the system. The foot-bearing sandstones have a thickness of 400 feet, and represent the reptiliferous sandstones of the Elgin area, though not overlain by Cornstones as in that district. The author, in conclusion, remarked that though Stagonolepis is decidedly Teleosaurian in its affinities, it does not consequently mark a Mesozoic group of rocks ; for...
Page 51 - Lingula-beds, the whole being overlain, as in Wales, by Dictyonema-shales. These rocks, on the east of the Herefordshire Beacon, are altered by trapdykes, which were shown to be of later date than those traversing the crystalline rocks before alluded to. Allusion was next made to the Upper Llandovery strata which overlie unconformably the primordial rocks just noticed, after which the several faults in the district were described in detail. Dr. Holl concluded with some remarks on the general relations...
Page 232 - to remember when geologists dogmatized on both these questions in a manner very different from that in which they would now venture to indulge. I believe that by far the greater number now incline to opposite views from those which were once most commonly entertained. On the first point it is worthy of remark that although a...
Page 186 - Much as these periods exceed our conception, they appear to be in harmony with the results of astronomical research, which contemplates spaces, motions, and cycles of periods too vast for words to express, or numerals to count, or symbols to represent. The greatest difficulty in obtaining trustworthy results as to elapsed time is found where it was least expected — among the later ctcnozoic deposits from rivers and lakes, and on the variable shores of the sea.

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