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110 issue, his baronetcy, like that bestowed on his confrère Murchison, became extinct.

In 1858, one year before the publication of Darwin's famous book, The Origin of Species, he revisited Sicily in order to make observations upon the structure of Etna, and, as already stated, he refuted the theory of "Elevation Craters"—the "cupolas" of the German geologists. This theory stated that all great volcanoes were formed of masses originally deposited in a horizontal position, and subsequently blown up into a conical form. Lyell proved that in the case of Etna, during the earlier periods of its history, the piling up of materials went on around a centre which is now situated at a distance of nearly four miles from the present focus of eruption. His "Memoir on the Lavas and Mode of Origin of Mount Etna" is to be found in the Philosophical Transactions for 1858.

In 1863 Sir Charles Lyell published his famous work on The Geological Evidences of the Antiquity of Man, with Remarks on Theories of the Origin of Species by Variation. In this marvellous book a vast amount of details and research are brought forward in regard to prehistoric man, and the times in which he lived. Concerning the Pleistocene alluvial deposits in many European valleys, there were found "works of art of the ages of iron and bronze, and of the later or Neolithic stone period. In the more ancient or Palæolithic gravels there have been found in