NOTES AND QUERIES. 
117 
tion between the two being sharply and clearly defined, (vide right hand side of 
the sketch). 
The cutting afforded by this quarry shows that the basalt, the ancient chalk- 
drift, and the chalk itself, have been denuded ; and a layer of dark brown clay, 
formed apparently exclusively of disintegrated basalt, spread over aU to the 
depth of eight feet. 
The surface of the chalk beneath its ancient flint drift, as well as the more 
recent basalt clay deposit, has been worn into hollows and cavities of variable 
width and depth ; and in those fiUed by the basalt clay, the quarrymen frequently 
find the fragments of deer's horns and bones. (See left hand side of sketch ait 
h, h). 
With regard to the probable age of this drift basalt clay, tliere are some who 
may probably suppose that it is comparatively recent ; and the product of rain 
and snow wearing away and washing down the basalt from the higher lands of 
the mountain on to its flanks. Such would be a hasty conclusion.- Rain 
acting on disuitegrating rock does not deposit its sediment, or fine detritus, on 
the flanks of hills ; but carries them by the floating power and velocity of its 
waters to the lowest lands of the plains, and eventually to the bed of the ocean. 
If that was the origin of the deposit, its formation should be still progressing ; 
but it is very evident that the contrary is the case. 
On carefuUy studying the facts presented to us in this quarry, it is clear that 
the era of the last great denudation was dl•a^ving to a close before the formation 
of this basalt clay, which must have been deposited as mud at the bottom of 
possibly a shallow sea or estuary. It belongs therefore to the Glacial or Escar 
Drift, which bears the same relation to the other rocks as this clay does to those 
beneath it. The horns of the deer, and bones of the same animal, or of others, 
may have been washed into the sea, and swept by tides and currents on to this 
bank of silt, through which they sunk till they rested on the surface of the 
chalk beneath. 
If this supposition be true, and I see no reason to question its correctness, 
we have evidence here to show that deer, and very possible other animals, 
existed in these latitudes, wliile the land presented a very different configuration 
to that which it now has ; and a large portion of what is now the north of Ire- 
land was more than seven hundred feet lower than at present, and therefore sub- 
merged beneath the level of the sea. — Truly yours, Geo. Y. iDu Noyek, Dublin. 
DiTHYROCARIAN CRUSTACEAN REMAINS AT PORTMADOC. — SiR, — Allow me to 
inform your readers that the " New Crustacean form allied to Dithyrocarus," 
referred to in your last number, page 74, occurs in this neighbourhood (Port- 
madoc), and has recently been colled ed by me from the lower Lingula beds at 
Wern. 
My specimen is the exact size of your woodcut, which is rather larger than 
the Skiddaw specimens lately sent me by ]Mr. Gregory, of 3, King William Street, 
Strand, who has, I understand, some very fine examples. — I am. Sir, yours 
obediently, John Ash, Portmadoc. 
Curious Geological Fact. — In a field, the property of ^Ir. Ronton, situate 
a short distance from the point where the Leeds and Liverpool Canal is crossed 
by the Midland Company's railway, at Idle, near Bradford, is a considerable 
hni, or piece of risiuq^ ground, which has been noticed to be gradually attaining 
greater elevation during a period extending over the last thirty years. There 
are even young men who remember the field being quite level, whereas now 
there is a mound near the middle of it. The cause of this singular elevation 
has given rise to much speculation. Some persons suppose that it is owing to 
the upward pressure of water in the bowels of the earth. — Times," Nov. 22, 
1860. W^hat does this mean? — Querist. 
We do not know the hill referred to, but we should think from the above 
