South-west and North of France, and South of Germany. 187 
contains nests of a singularly pure clay, and of the mineral 
called Lenzinite. (See Journal de Physique , 1822.) 
The alluvial matters are very abundant upon the base of the 
Pyrenees. They are divided into older , very much above the le- 
vel of the present rivers; and into modern ; and consist of pebbles, 
sand, rolled masses, marls with land-shells, like those found in 
Austria, and of various tuffaceous calcareous rocks . 
This last tertiary basin is distinguished from that of Paris, 
chiefly by containing molasse instead of plastic clay ; by wanting 
the upper fresh-water deposits ; by containing a coarse limestone, 
sandy above and chloritic below, and by showing scarcely any 
traces of gypsum. 
If these recent formations are different, the comparison of the 
secondary ones also presents some variations. The chalk in the 
north of France is not so much destroyed, and forms a whole 
basin. The coarse chalk of both countries differs ; but excepting 
in the great frequency of vegetable remain sand iron deposits 
in the ferruginous and green sand of the south, the northern 
similar formation is identical with that of Gascony. The Jura 
deposit is far more complete every where in the north of France 
than in the south ; from both sides the lias forms a line (in 
Normandy, Lorraine and Luxembourg), under the lower oolite 
and compact limestone ; then come the upper oolite and compact 
rocks, and in Normandy the coral rag, and the other newest 
beds of the English Jura deposit. 
The lias in Lorraine, he. shows many beds full of nests of 
hydrate of iron, and gives rise to extensive mining districts, 
(Haut Maine, Luxembourg). It is separated from the variegated 
sandstone, by some patches of quadersandstein at Vie Metz, and 
•especially in Luxembourg, (See Steininger’s map). This is a 
shelly freestone, sometimes pretty coarse. Under it is the shell 
limestone, muschelkalk* or second floetz limestone, which sur- 
rounds nearly the whole of the Vosges, and has all the charac- 
ters of the German one. Then comes the variegated sandstone 
of Lorraine, with its gypsum, salt-deposit, and subordinate beds 
of limestone, compact, or similar to the roggenstein, which in- 
dicates the . approach of the shell limestone, (muschelkalk.) 
If Bretagne and La Vendee have a great resemblance to the 
Pyrenees, the chain of the Vosges is ill most entirely different ; for 
