ANNIVERSARY ADDRESS OF THE PRESIDENT. Ixi 



aiices which are in reahty characteristic of a deep subterranean or 

 submarine origin. Volcanic rocks now forming at a certain distance 

 below the surface, or sedimentary strata which are in progress in 

 deep seas, can very rarely emerge and become visible to man till they 

 have acquired a high antiquity relatively to most of the lavas and 

 beds of mud, sand and pebbles which will be formed in the interval 

 of time between the origin of such subterranean or submarine rocks 

 and their exposure above ground. They cannot, except in a few very 

 disturbed regions, like the Alps, emerge from the sea, or break out 

 in the centre of a mountain-chain, till a series of grand revolutions of 

 the earth's crust has occurred throughout many large areas. Lofty 

 cones of lava and scoriae will have been piled up, old rocks will have 

 been denuded or displaced, bent or fractured, and new strata, thou- 

 sands of feet thick, will have been formed, besides the occurrence of 

 several important fluctuations in the organic world, before the nether- 

 formed products of fire or water are brought into view. Whenever 

 these do appear, their aspect will be strange and unfamiliar to human 

 observers, such as might well belong to bodies formed in a part of 

 the great laboratory of nature, to which man has no access. Such 

 singularity in outward form and internal texture will naturally be re- 

 ferred to an origin connected with the beginning of things, if the 

 mind be already prepossessed with a belief that we are studying the 

 monuments of a planet, which has been passing from a chaotic or 

 nascent state to one of order and maturity, especially if the peculiar 

 rocks in question are found invariably to have claims to a high rela- 

 tive antiquity. 



" Granitic eruptions," says M. de Beaumont, '* have become more 

 rare in the more recent epochs* ;" and doubtless it is most true, that 

 in the newer secondary and older tertiary formations, the granitic 

 rocks become more and more exceptional ; but had we lived in the 

 carboniferous or Permian epochs, we might, I conceive, mth equal 

 justice have declared the only granites then visible to be extremely 

 ancient. The more quartziferous varieties, together with a certain 

 class of metalliferous veins, posterior in date to the vegetation of the 

 coal period, such as are now known to the miners of Cornwall, or to 

 those of the Ural Mountains, would then have been unformed, or at 

 least invisible. The ages which have elapsed since the coal-measures 

 * Bulletin, 2nd Series, vol, iv. p. 1299. 



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