In the river-beds, however, and at some distance from the sea, older strata and eruptive rocks underlie the alluvium.
During and since the deposition of the rocks that underlie them the tract has been the scene of repeated terrestrial disturbances.
The fifth temple, that of Venus Pompeiana, lay to the west of the basilica; traces of two earlier periods underlie the extant temple, which was in progress of rebuilding at the time of the eruption.
We shall first give the general principles which underlie the methods for the dry extraction of copper, and then proceed to a more detailed discussion of the plant used.
While it is true that the instruments and methods of research in these two branches are quite different in their details, there is so much in common in the fundamental principles which underlie their application, that it is unprofitable to consider them as completely distinct sciences.