BASALT AND TRAP. 49 
Our section shows how closely the results of 
volcanic forces now in action are connected, 
both with the phenomena of basaltic formations, 
and also with the more ancient eruptions of 
greenstone, porphyry, syenite, and granite. The 
intrusion both of dykes and irregular beds of un- 
stratified crystalline matter, into rocks, of every 
age and every formation, all proceeding upwards 
from an unknown depth, and often accumulated 
into vast masses overlying the surface of strati- 
fied rocks, are phenomena coextensive with the 
globe. 
Throughout all these operations, however tur- 
bulent and apparently irregular, we see ultimate 
proofs of method and design, evinced by the 
uniformity of the laws of matter and motion, 
which have ever regulated the chemical and 
mechanical forces by which such grand effects 
have been produced. If we view their aggre- 
gate results, in causing the elevation of land 
from beneath the sea, we shall find that volcanic 
forces assume a place of the highest importance, 
among the second causes which have influenced 
the past, as well as the present condition of the 
globe ; each individual movement has contri- 
buted its share towards the final object, of con- 
ducting the molten materials of an uninhabit- 
able planet, through long successions of change 
and of convulsive movements, to a tranquil state 
GEOL. E 
