File:The Quarterly journal of the Geological Society of London (12645282143).jpg

1848.. MURCHISON ON THE STRUCTURE OF THE ALPS. 221
with the submarine deposits, — a class of strata now too well known
to require further illustration f. At the same time I know that this
region also abounds in igneous rocks of a truly erui)tive character
which have penetrated and cut through the whole of the stratified
masses. Examples of both these classes of former volcanic or plu-
tonic action are sometimes to be seen in the same hill, as exhibited in
the above woodcut. The chief masses or ledges of nummulitic lime-
stone which thus surmount the scaglia, dip on the whole southwards
to pass under the marls, tuffs, sands and limestone of the undulating
hills of the Vicentine, and thus the nummulitic limestone is fairly
seen to constitute the base of that shelly group, even in a tract much
traversed by basaltic matter. But in proceeding to the west and
south-west of Schio, the igneous rocks so abound, that a regular
sequence, I repeat, is not traceable for any considerable distance. To
the north of St. Orso near Schio, indeed, the effects of the intrusion
of a great mass of porphyry have been such as completely to invert
the strata and to fold back the cretaceous rocks and make them over-
lie first the nummulitic and then the other and younger tertiary