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feldt on the Raab towards Radkersburg, and a section made along 

 their western face offers the following phenomena. 



At Straden, shelly sands and pebble beds are capped by irregularly 

 columnar basaltic lava with olivine, &c. 



The hill of Poppendorf exhibits in great detail the structure of this 

 younger tertiary zone. Marls, sands, and conglomerates, occupy its 

 lower and middle parts, together with many beds of calcareous, shelly 

 grits, indurated marlstone, limestone, &c. the whole being very mi- 

 caceous, and the organic remains identical with those of Radkersburg. 

 These are overlaid by micaceo-calcareous sand, containing concre- 

 tionary masses of a perfect oolite which is quarried as a building stone, 

 and which differs from the great oolite of Bath only by its concretionary 

 structure and the tertiary shells associated with it. 



The fine-grained oolite passes upwards into other concretionary 

 beds something like English cornbrash, and the whole is surmounted 

 by micaceous sands and marls. In an adjoining hill near Gnaess, 

 these beds inclosing shells alternate with volcanic peperino made 

 up of basaltic lava, scoria, vitreous felspar, olivine, pyroxene, the 

 detritus of tertiary rocks and shells, &c. ; and on the summit the 

 peperino in a more compact state is quarried as a building-stone* 

 The conical hills of Gleichenberg, overlying the shelly sands, are 

 entirely of volcanic origin, and were probably the centre of igneous 

 eruption in these parts. Here the predominating rock is a coarse 

 trachyte used for millstones (felspathic porphyry, probably analogous 

 to the Porphyre molaire of Beudant), and with it are associated ba- 

 saltic lavas, scoria, and fine peperino, which near Hainfeldt repose 

 upon the sands. Considerably to the north of the Raab the volcanic 

 conglomerate on which the castle stands is also recumbent upon the 

 shelly sands and pebble beds. 



From these and several other examples in the neighbourhood, the 

 authors infer, that no tests can be established by which the relative 

 ages of these various igneous rocks can be fixed, since the same ter- 

 tiary strata are in one place covered by basaltic lava, in a second by 

 trachyte, in a third by volcanic conglomerate, whilst in a fourth they 

 alternate with peperino. 



In conclusion they remark : — 



That the lowest tertiary strata near Eibeswald must from their 

 high inclination have been considerably elevated after their de- 

 position. 



That the various groups described, unquestionably represent, — 

 1st, the Paleotherian and Calcaire grossier period : — 2ndly, The Crag 

 and middle Sub-Apennine formations : — 3rdly, Newer deposits identi- 

 cal with those of the adjoining bay of Vienna, which is shown to have 

 been connected with the bay of Gratz by the intervention of the great 

 tertiary sea which once occupied all the plains of Hungary. 



That the volcanic forces in this region were first called into action 

 during the most recent of these periods, and were probably continued 

 in activity through the long succession of ages in which the sea was 

 spread over these countries. 



Lastly, That the volcanic rocks stand out in such prominent masses, 

 as to offer emphatic proofs of the enormous degradation and waste 



