80 
BASALTIC ROCKS, 
loosely aggregated mass of granular carbonate of lime, resembling 
coarse white sand. These calcareous sparry grains seem to be obscurely 
dodecahedral, and amongst them lie a few sparry crinoidal columns. 
As we recede from this centre, the limestone resumes by slow degrees 
somewhat of its ordinary character, passing through stages of white, 
bluish, and blue granular limestone, which grows more and more com- 
pact, darker, and harder, till its ordinary aspect is restored within a mile 
in the directions where the Whin is rapidly attenuated, but at greater 
distances where its thickness remains considerable. Under the same 
\\ iddybank scars Professor Sedgwick ascertained the production of olive 
brown, or green garnets, in the cells of the anomalous fragmentary 
bed which supports the trap. 
Since it is about Caldron snout that the Whin exhibits most thick- 
ness, and the greatest effects of heat in the rocks both above and 
below, it seems a plausible hypothesis to consider it as having been 
raised up through an opening in the lower limestone rocks & at this 
place, and to have flowed hence in all directions for some distance, 
growing however very thin to the west, and vanishing totally to the 
south. The long ridge of basalt which extends down Teesdale, from 
Caldron snout to Lonton, may very probably indicate the line* of a 
volcanic fissure, communicating with the presumed great opening at 
Caldron snout. Other such openings and fissures, along the line from 
Brampton to Belford, will explain the general conformity of the Whin 
sill to the limestone series. 
But we may now inquire what proofs occur of mechanical disturb- 
ance produced by the eruption of the basaltic lava ? On this subject 
Professor Sedgwick has left little to add to his very satisfactory des- 
cription of the phenomena at White force, (Cronkley scar), in Widdy- 
bank scar, and near Lonton ; I shall therefore adopt his descriptions 
merely adding one additional instance, not visible when he made his 
survey. 
Lonton.— Here, in the Lune, portions of the subjacent hazle are 
