i ee, ee as ee 
1822.] Mr. Weaver's Geological Remarks. 91: 
ing it has been somewhat different. In making this allusion, 
however, I am far from meaning to deny that the fourfold divi- 
sion into the fundamental old red sandstone, carboniferous lime- 
stone, millstone-grit and shale, and coal formation, is very 
descriptive, wherever applicable, since it enables us to consider 
distinctly the several links ofa chain, which constitute in them 
selves a complete system of one great era; but this division 
cannot always be strictly made, e. g. in most parts of the Scotch 
great coal tract. 
After the full consideration given to the rothe todtliegende form- 
ation, extending from the Hartz beyond the banks of the Saale, that 
of the Forest of Thuringia may be disposed of in few words. 
The old red sandstone is there found in great force, frequentl 
alternating with porphyry and trap (e. g. vol. iv. p. 107—116), 
reposing principally on primary rocks, and clearly showing by 
its composition, like that of Mansfeld Xc., that it originated from 
their detritus (vol. iv. p. 67—99.) The coaly shale and coal 
formation, connected with the old red sandstone, is unequally 
distributed, being also occasionally associated with limestone 
and porphyry, and coming in the course of its extent not unfre- 
quently in contact with primary tracts, the coal field reposing in 
some instances upon granite (e. g. vol. iv. p. 167, 168). 
I will now consider the red sandstone formation described by 
Von Raumer. But previously let me observe that, as the princi- 
pal object of that author’s researches was to ascertain the grand 
features and relations of the country, we are not to expect that 
great precision, or minute detail, that are so generally observable 
in the works of Freiesleben. ‘Still, however, the leading facts 
can hardly admit of dispute. For the general positions, I refer 
to the Annals of Philosophy for Oct. 182], p. 248—250. 
The red sandstone formation which occupies so large an 
expanse on the southern side of the Riesengebirge, extending 
. from Schatzlar, appears to be destitute of coal. It dips 8. 
But proceeding eastward from that town, it is found connected 
with an extensive coal field, sandstone conglomerate forming 
throughout the great basis, the character of which varies 
according to that of the adjacent primary or transition tracts 
upon which it reposes, enveloping pebbles and fragments of 
gneiss, micaslate, granite, hornblende slate, clayslate, quartz, 
&e. (Von Buch, Geog. Beob. vol. i. p. 85—93 ; Von Raumer, p. 
92.) The carboniferous series ranges along the south-western 
side of the Eulengebirge toward Glatz, a distance of about 35 
miles. Having given a summary of its general relations in the 
work referred to above, it may be sufficient to add in this place 
a few remarks on the general disposition of the tract. 
This carboniferous series is almost entirely overlaid on its 
