| → the 1859 1860 |
| (it makes no great difference whether the upheaval was sudden, or, as most geologists now believe, was very slow and effected by many starts), the 1861 |
| (it makes no great difference whether the up-heaval was sudden, or, as most geologists now believe, was very slow and effected by many starts), the 1866 |
|
| → to 1859 1860 |
| of the land to 1861 1866 |
|
| → intermediate hilly country and look on the one hand 1860 |
| North Downs and to look 1859 |
|
| → North Downs, and on the other hand at the 1860 |
| distant 1859 |
|
|
having been much struck with the evidence of denudation, when viewing volcanic islands, which have been worn by the waves and pared all round into perpendicular cliffs of one or two thousand feet in height; for the gentle slope of the lava-streams, due to their formerly liquid state, showed at a glance how far the hard, rocky beds had once extended into the open ocean. The same story is still more plainly told by faults,— those great cracks along which the strata have been
on one side, or thrown down on the other, to the height or depth of thousands of feet; for since the crust
→the
surface of the land has been so completely planed down by the action of the
that no trace of these vast dislocations is externally visible. |
|
| The Craven fault, for instance, extends for upwards of 30 miles, and along this line the vertical displacement of the strata has varied
600 to 3000 feet. Prof. Ramsay has published an account of a downthrow in Anglesea of 2300 feet; and he informs me that he fully believes there is one in Merionethshire of 12,000 feet; yet in these cases there is nothing on the surface
→to
show such prodigious movements; the pile of rocks on the one or other side having been smoothly swept away. The consideration of these facts impresses
mind almost in the same manner as does the vain endeavour to grapple with the idea of eternity. |
|
| I am tempted to give one other case, the well-known one of the denudation of the Weald. Though it must be admitted that the denudation of the Weald has been a mere trifle, in comparison with that which has removed masses of our palæozoic strata, in parts ten thousand feet in thickness, as shown in Prof. Ramsay's masterly memoir on this
it is an admirable lesson to stand on the
→intermediate hilly country and look on the one hand
at the
→North Downs, and on the other hand at the
South Downs; for, remembering that at
|
