Chap. XIII.] ZECHSTEIN AND AMOKPHOUS DOLOMITE. 
321 
The geologist who follows the Zechstein along various tracts is constantly, in- 
deed, induced to account in a similar manner for a sudden expansion of that 
bedded deposit into amorphous dolomite; for, although there are numerous 
tracts where the upper portion of the formation is a regularly bedded magnesian 
limestone resembling that of Britain, yet as we often see the rock at the distance 
of a mile from where it is a flat-bedded limestone of small dimensions suddenly 
swell out into a precipitous, amorphous mass, characterized by caverns and irre- 
gular joints, it seems impossible to doubt that this change has also been caused 
by a powerful metamorphosis. This rapid change can be observed by any one 
who, frequenting the baths of Liebenstein on the west flank of the Thiiringer- 
wald, shall first examine the stratified Permian hills to the west of Gliicksbrunn, 
with their strata of Weiss-liegende and Kupfer-Schiefer surmounted by Zech- 
stein and red flaggy sandstone (Lower Bunter), and then cross from the escarp- 
ment over several protrusions of porphyry in the valley to the east, which have 
much altered the strata in contact, until he is stopped by the precipitous face of 
the towering masses of dolomite which suddenly rise up and constitute pic- 
turesque eminences 200 feet above the low tract, as in this woodcut. 
Conversion op bedded Zechstein into amorphous Dolomite. 
W. Hills ET.W. of Gliicksbrunn. Valley of Gliicksbrunn. Altenstein. E. 
d. Koth-liegende (not seen in this part of the tract), e. Weiss-liegende with some 
copper-ore. /. Kupfer-Schiefer, rich in copper-ore and fossil Fishes, g. Zechstein, 
with fossils, h. Red sandstone (roof of the Zechstein). g*. Altered Zechstein (Dolo- 
mite). *. Eruptive rocks, m. Micaceous schist and altered rocks. 
The identity of the amorphous subcrystalline dolomite of the cliff with the 
stratified limestone of the adjacent lower country is here demonstrated by the 
clearest evidence ; for the same species of shells which exist in the flat-bedded 
strata, g, of the low arable hills on the east are here detected in the unbedded 
wild cliffs of dolomite with their deep fissures and long caverns, g*. 
In thus briefly alluding to the striking features of amorphous gypsum and 
dolomite which reoccur at intervals in many parts of the range of these lime- 
stones of the Permian group, it is also to be noted that along these lines of me- 
tamorphism the same rocks often contain rich masses of spathose and hematitic 
iron-ores. This is specially observable on the western flank of the Thiiringer- 
wald, to the east and south of Liebenstein, where the Zechstein has been intruded 
upon by porphyritic and granitic rocks. 
In advancing from the environs of Saalfeld, where the Zechstein and Weiss- 
liegende (the latter becoming red in parts) rest upon the edges of the Upper 
Devonian and older Carboniferous rocks, we meet with numerous knolls of gyp- 
sum, both stratified and amorphous, with much iron-ore, both of which have been 
described by Richter f ; whilst at Essig and Possneck the calcareous matter 
again rises up in apparently unbedded dolomitic bosses, which on disintegration 
have afforded numerous characteristic fossils %. 
t Einladungsprogramm der Real-Schule, &e., Saalfeld, p. 21. 
I The Altenburg of Pb*ssneck has afforded to the researches of the Rev. Mr. Schubert a fine collec- 
tion of fossils. 
Y 
