flcetz rocks. 7* Coal-Formation. Steinkohlen-Gebirge.—Werner. l. This formation is of great importance. It is particularly characterized by the coal it contains. Werner has afcertained three diftinct formations, without including the beds of coal found in fand- ftone and limeftone formations. The firft or old- eft formation is denominated the Independent Coal Formation, becaufe the individual depofitions of which it is compofed are independent of each other, and are not connected. The fecond is that which occurs in the neweft flcetz-trap formation. The third that which occurs in alluvial land. Werner obferves that a fourth formation might be added, which would comprehend peat and other fimilar fubftances ; fo that we would have a beau tiful and uninterrupted feries, from the oldeft for mation to the peat which is daily forming under the eye. Thefe three principal formations are diftin- guiflied from one another, not only by relative age, the kind of rocks, and the form of their llratifica- tion, but alfo by the particultw kinds of coa* they contain. Thus, the independent formation contains exclufively caarfe coqf,foliated coal, can- nel-coal, JIate-coal, a kind of pitch-cool, and Jlaty glance-coal *. 1 he foi^ition in the npweft flcetz- g * I firft found flaty gltffice-eoal in this formation in the illand of Arran, afterwards in Dumfriesfhire and Ayrlhire, and
