ROCK. 



appear lo be decidedly distinguished 

 from those of the other periods. 



The floeiz rocks, formed by risings of 

 the waters after the creation of animals 

 and vegetables, seldom reach to a very 

 great height : those of what is termed the 

 newest fl'oetz trap formation form, how- 

 ever, an exception ; since they cover the 

 summits of very high mountains, and 

 show their formation to have been at a 

 different period, and when the waters 

 were higher than when the other flcetz 

 rocks were formed. Of these rocks lime- 

 stone is the most prevalent ; and in the 

 rocks of this formation bituminous fossils, 

 and the petrifactions of vegetables and 

 animals, are very numerous, and in great 

 variety. 



The rocks of this class are the follow- 

 ing : 1. The first sand-stone formation, 

 which is called the old red sand-stone ; 

 the grains are usually quartz and flinty 

 slate, cemented by iron-shot clay. 2. 

 A r ariegated sand-stone, or second sand- 

 stone formation ; which is marked with, 

 and is also disposed in, layers of different 

 colours. 3. Third sand-stone formation ; 

 which is always white, and appears to be 

 of much later formation than those just 

 mentioned. 4. Partial sand-stone forma- 

 tion. 5. Floetz lime-stone, is a simple 

 rock, and is more distinctly stratified than 

 any other rock. Two distinct formations 

 are described ; the first floetz lime-stone, 

 ' and the second floetz, or shell lime-stone. 

 6 Floetz gypsum is also a simple rock, 

 and is more or less distinctly stratified. 

 Of these rocks also there appears to be, 

 beside others, two principal formations. 

 7. Rock-salt formation. It is mostly found 

 in short, but thick beds, in clay in a state 

 between common and indurated clay. 8. 

 Chalk is reckoned one of the newest of 

 the floetz formations. It generally con- 

 tains flint, and the petrifactions of marine 

 animals. 9. Floetz trap is supposed by 

 Mr. Jameson to result from a formation 

 different from that which Werner has 

 named the newest flcetz trap. 10. Coal 

 formation. Werner describes three for- 

 mations of coal ; the oldest, or indepen- 

 dent coal formation ; that which occurs in 

 the newest floetz trap formation ; and that 

 which occurs in alluvial land. 11. New- 

 est floetz trap formation, which includes 

 several rocks, particularly basalt, wacke, 

 grey-stone, porphyry-slate, and trap-tuff, 

 which are its peculiar and characteristic 

 rocks. Those which occur in it, as well 

 as in the other floetz formations, are 

 green-stone, amygdaloid, pitch-stone, ob- 

 sidian, pumice, compact felspar, clay- 



stone ; gravel, sand, and clay ; sand-stone, 

 clay iron-stone, lime-stone, iron-clay, and 

 coal. The form, and other visible cha- 

 racters, of many of the mountain rocks 

 are frequently sufficient to point out. 

 their nature to the attentive observer. 

 Granite is characterised by its very high 

 and precipitous cliffs and peaks ; gneiss is 

 less lofty, and its summits are less steep 

 and abrupt ; and the mountains of mica 

 slate are still less lofty, and bear more of 

 a rounded form. Clay-slate mountains 

 are generally less lofty than those already 

 noticed, and their cliffs are still less steep 

 and rough. Primitive lime-stone some- 

 times presents lofty peaks, like those of 

 granite ; but the mountains containing 

 in general assume the characters of gneiss 

 mica-slate, or clay-slate, with which it i; 

 in general found. Rocks of primitive tra] 

 are generally lofty, steep, and conicj ' 

 " No rock," Mr. Jameson observes 

 " presents a greater variety of exterr 

 appearance than the sand-stone. Its v: 

 lies are deep, rocky, and romantic ; its 

 hills are conical, steep, and cliffy ; and it 

 often presents grand colossal pillars, 

 which, from their number, and variety of 

 their shape, form most striking rocky 

 scenes." Floetz lime-stone assumes ven 

 different forms from those already parti 

 cularised, being extended in large, fla 

 hills, intersected by steep vallies. Chall 

 in some situations forms hills of consider 

 able height, which are generally round 

 ed, with an extensive base. 



The position, extent, and direction o 

 the several strata of different formations 

 either taken with or without reference to 

 the fundamental rock, yield very con 

 vincing testimony in favour of the opi 

 nions delivered by the celebrated Werne 

 respecting the formation of the earth 

 (See GEOLOGY.) Previously to viewing 

 the illustration of his theory in the forma 

 tion of a suite of rocks, it may be neces 

 sary to particularize some of the pecu 

 liarities in the formation of differen 

 rocks, and to show the different term 

 by which they are expressed. The for 

 mations themselves are distinguished a 

 universal or partial, and as unbroken o 

 broken. The strata are considered a 

 conformable, or unconformable, with th 

 direction of the fundamental rock ; anc 

 overlying, when lying over the ends o 

 the strata of the fundamental rock. The 

 are said to be straight, when disposed i 

 one direction on the fundamental rock 

 when they turn round it, leaving the to 

 uncovered, mantle-formed ; and whe 

 they also cover its extremities, saddle 



