1823.] the principal Mountain Chains of Europe. 145 



coal appears to range many miles on the south-west and south 

 of Hanover between Osnabruck and Hildesheim, but we cannot 

 refer to any description of it; it may probably form the prolong- 

 ation of the northern line of coal fields which we lately traced a* 

 far as the Ruhr. 



(K.) Coal and Porphyry Formations surrounding the Hartz* 



These associated formations succeed to the slate mountains of 

 the Hartz, near the east end of which they present themselves in 

 three points : 



1 . The Opperode district. 



2. The Ilefield district. 



3. The Petersbirge district. 



Both the first lie immediately on the slate, and form a portion 

 of the Hartz chains. The third forms an insulated district in 

 the Saale kreisse. The coal formation presents the ordinary 

 alternations of bituminous shale and coal sandstone, of the usual 

 varieties, and some calcareous beds with marine fossils. Three 

 beds of coal are sometimes found ; the principal variety is slate 

 coal. 



1. Near Opperode (on the north-east of the Hartz), the coal 

 lies under, and in parti* a l s0 in the red sandstone ; no porphyry 

 is found in this tract. 



2. But in the Ilefield district]; (on the south-east of the Hartz), 

 porphyry prevails near Neustadt. The more ancient members of 

 this formation pass immediately into the greyvvacke through 

 modifications approaching to hornstone rocks. The younger 

 members are mixed with more clay, become sandy and conglome- 

 rated, and thus pass into the red sandstone. The coat strata lie 

 between the porphyry and the slate hills, so that they have the first 

 place in the order of superposition (sie ersten zum hangenden 

 haben). In the upper formations, the conglomerates and sand- 

 stones exhibit themselves. 



3. The Petersbirge. This is a great mass of the porphyry 

 formation bounded by Lobegun, Wettin, Halle, Landsberg, Bitter- 

 fielcl, and Zorbig (lying a few leagues south-east from the Hartz). 



* I have abridged (but without any other alteration than that of condensation) this 

 account from Keferstein (Teutschland, p. 188, No. I). I have done this because the 

 statements I formerly published have been controverted by Mr. Weaver. It is well, 

 therefore, to call in an impartial witness as arbitrator. I must leave the reader to judge 

 towards whicli side the evidence thus introduced inclines. 



+ This is the part which Freisleben separates from the true coal formation ; it extends 

 to Meisdorf and Endorf, and is coloured in the map accompanying his work as rothe- 

 todte; but that map exhibits also the true coal formation as here interposed between the 

 rothetodte and the transition rocks. 



J The true coal formation lies (see the map accompany Freisleben) considerably on 

 the north of Xcustadt. The coal beds described by him as subordinate to the rothe- 

 todte are on the contrary on the south-east of that town, extending thence towards Ilc- 

 licld. The whole of this tract is coloured as rothetodte in the map, which presents the 

 regular series; transition rocks, coal, porphyry, rothetodte, overlying each other in 

 succession. 



New Series, vol. v. l 



