Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: June 21, 2025
The mountains, which then separate these rivers from the plain, are composed of schistus and great collections of water-worn gravel which had come from the mountains of the Pyrénées.
It is not often indeed, that, in those alpine regions, any considerable tract of country is to be found, where an example so convincing is exhibited. It is more common for those mountains of primary strata or schistus to rise up in ridges, which, though divided into great pyramids, may still be perceived as connected in the direction of their erected strata.
At Jedburgh the schistus was vertical, and the strata horizontal; and there was interposed a compound bed of pudding-stone, formed of various water-worn bodies, the gravel of the schistus strata, and porphyries. Here again, though we have not a regular pudding-stone, we have that which corresponds to it, as having been the effect of similar circumstances.
If, therefore, strata had been deposited upon broken and bare rocks of schistus, it is probable that these had been sunk in the sea after having been exposed to the atmosphere, and served the purpose of land upon the globe.
With this view I have often considered our schistus mountains, both in the north and south; but I never found any satisfactory appearance from whence conclusions could be formed, whether for the question or against it.
First, there is no distinction to be made of what is termed primary and secondary mountains, with regard to the position of their strata; every different species of stratum, from the stratified granite and quartzy schistus of the Alps to the oolites of the Jura and Saleve, being found in every respect the same; whether this shall be supposed as arising from their original formation, or, according to the present theory, from a subsequent deplacement of strata formed originally in a horizontal situation.
Word Of The Day
Others Looking