30 RICHTHOFEN — NATURAL SYSTEM 
sequent eruptions of those belonging to other orders. At several places it has 
been observed to intersect Eocene strata, and to expand above them. The coun- 
try of Nagybdnya, Felsébdnya and Kapnik, the celebrated silver-bearing veins of 
which are enclosed in propylite, offers especially conspicuous illustrations ; not less, 
from the descriptions given by G. Stache, the ‘‘ Erzgebirge ” of Transylvania, where 
the same kind of rock is rich in mineral veins. In this country, hornblendic propylite 
forms an older series, followed by eruptions of highly quartziferous varieties. In 
both countries, but chiefly in that first named, and at several other places along the 
southern slope of the Carpathians, andesite may be seen intersecting propylite in large 
massive dykes, and towering up above it in mountain ranges. Andesite composes 
entirely the Hargitta-range, which extends over one hundred miles in length, and 
twenty-five in width; the Vihorlat-Gutin-range, which is of still larger dimensions, 
and the Hperies-Kaschau-range ; all of which are densely wooded, and of a gloomy, 
monotonous aspect. The only change observable on their summit ranges is a more or 
less dark color of the rock, occasioned by the predominance of augite or hornblende in 
its composition, (the augitic varieties being invariably of more recent age than the 
hornblendic), while their slopes, and particularly their ends, present a much greater 
variety in rocks as well as inscenery. It is here that the more silicious volcanic rocks 
are encountered. Trachyte is of rare occurrence ; but it forms several isolated cones, 
some of which, on account of their prominent position, were crowned by castles in the 
middle ages. Rhyolite is much more frequently met with, bursting forth on the 
flanks, and skirting the foot of the andesitic ranges, particularly where they verge 
towards the Hungarian plains, which in the rhyolitic epoch were still covered by a 
shallow and slowly retiring sea. It projects against this in promontories, which are 
now covered by the most celebrated of the Hungarian vineyards, those of Tokay 
among others. The boundaries of these vineyards towards the adjoming beech forests 
mark the dividing line between rhyolite and andesite. An interesting mode of occur- 
rence of the former may be witnessed in large circular or amphitheatrical basins which 
are surrounded by andesite. Such places are the theater, especially, of the volcanic 
activity connected with the outbreak of rhyolite, and abound in endless hyaline vari- 
eties of the same. Telkibanya is the most interesting among the localities of this 
description. There is no lack of evidence to prove that trachyte and rhyolite are both 
of more recent age than andesite, while the assertion that trachyte preceded rhyolite 
in age, rests only on a few though conclusive observations. Basalt occupies a singular 
position in the geology of Hungary. It keepsaltogether aloof from the places occupied 
by the other four orders of voleanic rocks, and forms extensive, though isolated, hills at 
some distance from them, scattered over a wide range of country. It would be difficult 
to determine its relative age, but for the voleanic sediments which were of formation 
contemporaneous with the ejection of the different volcanic rocks, and have been spread 
over wide areas at the bottom of the then existing sea, with fossils occasionally imbedded. 
In several localities, especially in the neighborhood of Kaschau, basaltic sediments may 
be seen, covering those composed of rhyolitic matter, while at Gleichenberg in Styria, 
Mr. Franz von Hauer has observed fragments of rhyolite enclosed in basalt. 
The observation of these relations in Hungary and Transylvania has first given 
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