United States or Moldova ? Vote for the TOP Country of the Week !
It is the rough argillaceous sandstone that accompanies the coal-measures in this part of Wales, and a moderate force gives it quite a rocking motion, which can be easily continued with one hand. It stands nearly in equilibrium upon a pivotal rock beneath.
The burrows of worms run down perpendicularly or a little obliquely, and where the soil is at all argillaceous, there is no difficulty in believing that the walls would slowly flow or slide inwards during very wet weather.
Some of the argillaceous wackes are of a dark green colour, others, pale yellowish-green, and others nearly white; I was surprised to find that some of the latter varieties, even where whitest, fused into a jet black enamel, whilst some of the green varieties afforded only a pale gray bead.
The "alum-schists," as they are called in Sweden, are horizontal argillaceous rocks which underlie conformably certain Lower Silurian strata in the mountain called Kinnekulle, south of the great Wener Lake in Sweden.
The examination of fossil coal fully confirms those reasonable suppositions. For, first, The strata that attend coal, whether the sandstone or the argillaceous strata, commonly, almost universally, abound with the most distinct evidence of vegetable substances; this is the impressions of plants which are found in their composition.
Thus in La Brenne, a tract of 200,000 acres resting on an impermeable subsoil of argillaceous earth, which ten centuries ago was covered with forests interspersed with fertile and salubrious meadows and pastures, has been converted, by the destruction of the woods, into a vast expanse of pestilential pools and marshes.
In the most hardened part of the mass the fossil shells, principally Producti, are nearly obliterated; yet even here their impressions may frequently be traced. The argillaceous limestone undergoes analogous mutations, losing its earthy texture as it approaches the dike, and becoming granular and crystalline.
In the lower or front hills the rock was argillaceous, of a hard slaty nature, and inclined at an angle of about 45 degrees from the horizontal. This formation was frequently traversed by dykes of grey limestone of a very hard texture.
Not only is the bituminous matter of coal found mixed in every different proportion with the earthy or uninflammable materials of strata, but the coaly or bituminous composition is found with perhaps every different species of substance belonging to strata. This is certain, that we have the coaly matter intimately mixed with argillaceous and with calcareous strata.
The façade has not been constructed; all that we see of it is a great naked, scarified wall similar to a leper's plaster. There is no light within. A line of small round bays and a few windows fill the immensity of the edifice with a gray illumination; it is bare, and the argillaceous tone in which it is painted depresses the eye with its wan monotony.
Word Of The Day