142 GEOGNOSY AND GEOLOGY. 
moderately high, dome-shaped hills, alternate with deeply cut valleys, their 
slopes provided with rough and rugged rocks. When of Alpine height, this 
rock exhibits heights, sharp combs (horns, needles, teeth), separated by valleys, 
whose steep sides run up from immeasurable depths. Transverse valleys, 
contracting and widening, with terraced slopes, over which dash foaming 
torrents, divide the heaven-aspiring rocks. 
The ground resulting from the weathering of the bottom series varies 
much with the subjacent stone. That produced from feldspathic rocks, as 
gneiss, whitestone, é&c., furnishes a mixed, loose, and exceedingly fertile 
soil, highly favorable to vegetation, on account of its richness in potash, 
soda, and alumina. ‘The case is different with the non-feldspathic crystalline 
schist: these generally decompose into a sterile, poor soil. Marble and 
dolomite separate mutually into a’ ©: and dolomitic sand, this division 
being facilitated by a proportion oi iron pyrites. The swelling of the 
latter produced by oxydation, crumbles down the rock with irresistible 
force. 
The bottom series, which not unfrequently form entire mountains and 
mountain chains, occur in Norway, Sweden, Finland, Great Britain, in the 
Hartz and Thuringia (only in traces), in the Saxony Erzgebirge, in 
Bohemia and Moravia, in the Spessart, the Odenwald, the Black Forest, 
and on the Italian side of the Alps; also, in the Cevennes, in Galicia and 
Portugal, in middle and western France, in the Pyrenees, the Sierra Nevada, 
the Northern and Southern Apennines, Hungary, Siebenbiirgen, and the 
neighboring region of the Danube. In other countries than Europe, it is 
found in Asia, from the Ural to Siberia: in the Himalayas and the 
neighboring mountains. In New Holland and North America, it occurs 
in great extent. 
Mippue Series. 
The essential geognostical character of the middle series consists in its 
resting on the bottom, and in being covered by the top series. The species 
composing this series are unquestionably Neptunian, being partly chemical 
formations of water, and partly mechanical deposits ; they thus exhibit both 
isonomic’ and heteronomic formations, which, in the vicinity of abnormal 
masses, have experienced certain modifications. The occurrence of carbonate 
of lime is one of the principal characteristics of the middle series, here — 
presenting its highest degree of development. It is either compact 
limestone or crystalline marble, and of various degrees of purity. It 
generally contains admixtures of carbonate of magnesia, or of alumina, in 
ereater or less quantity. The presence of the former converted it into 
dolomite, of the latter into marl; both together, into magnesian marl. Next 
in quantity and extent to limestone, comes silex. 
Various salts, as gypsum, anhydrite, rock salt, carbonate of iron, &e., 
are very abundant; carbon, also, is extensively distributed, and by its 
combinations with oxygen and hydrogen, sufficiently proclaims its organic 
origin. The occurrence of veins, especially of native metals, is less frequent 
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