NEW 



[313 ] 



NEW 



laceous, and is sometimes found to 

 contain mica, and masses of rock- 

 salt and gypsum. It affords a good 

 and handsome stone for building 

 purposes in some parts, when but 

 slightly coloured. It does not 

 abound in organic remains; among 

 its conchifera? may be enumerated 

 Plagiostoma, Avicula, Mytilus, Tri- 

 gonia, and Mya. Natica, Turritella, 

 and Buccinum may be included in 

 its genera of molluscs. By some, 

 the new red sandstone has been 

 divided into three series; the upper, 

 the middle, and the lower beds. Sir 

 R. Murchison proposes a four-fold 

 division of what he terms the new 

 red system, namely: 1. Saliferous 

 marls, &c. 2. Red sandstone and 

 quartzose conglomerate. 3. Cal- 

 careous conglomerate = magnesian 

 limestone. 4. Lower red sandstone. 

 Over a large part of England the 

 new red sandstone rests unconform- 

 ably upon the carboniferous group, 

 showing that the latter was dis- 

 turbed, dislocated, and partially 

 removed, before the former was 

 accumulated upon it ; there is, 

 however, reason to believe that in 

 other parts of the European area 

 deposits still continued quietly to 

 be thrown down upon undisturbed 

 parts of the carboniferous series, so 

 that no real line of separation can 

 be well established between them. 

 It is a very extensive deposit, 

 stretching, with but little interrup- 

 tion, from the northern bank of the 

 Tees, in Durham, to the southern 

 coast of Devonshire. It is almost 

 needless to observe, when we con- 

 template the red sandstone series 

 as a whole, and consider that it is 

 in great measure composed of matter 

 which must have been deposited 

 from water, where it was, for the 

 time, mechanically suspended, that 

 great variations should be expected 

 at the same geological levels ; here 

 clay or marl being found, there 

 sandstone or conglomerate, while, 



occasionally, calcareous matter 

 should be dispersed among it, under 

 favourable circumstances, in suf- 

 ficient abundance to constitute nu- 

 merous beds of limestone. 



When this deposit appears as a 

 sandstone, its characters differ 

 greatly in different places; it is 

 occasionally calcareous, and some- 

 times of a slaty texture. Above 

 all, this extensive deposit is re- 

 markable for containing masses of 

 gypsum, and the great rock-salt 

 formation of England occurs within 

 it, or is subordinate to it. 

 " Whether considered in its central 

 or in its lower member," says 

 Sir R. Murchison, " there is no 

 system of rocks, which occasionally 

 offers greater difficulties for deter- 

 mining its real laminse of deposit 

 than the new red sandstone. Besides 

 the joints or fissures, the diagonal 

 lines of false stratification are some- 

 times so prevalent, that is only by 

 tracing at wider intervals the true 

 laminee of deposit as marked by 

 herbage or moss, that we can 

 correctly ascertain the real dip of 

 the strata." 



A very remarkable discovery was 

 made in 1828 of the foot-marks of 

 some unknown quadruped in strata 

 of new red sandstone, three miles 

 from Lochmaben in Dumfries- shire. 

 They were found forty-five feet un- 

 der the present surface ; the strata 

 are inclined thirty-seven degrees. 



RED SANDSTONE GEOUP. This 



includes all those deposits found 

 below the lias group, and above 

 the carboniferous group. It con- 

 tains the red or variegated marls 

 (marnes irisees, keuper), the mus- 

 chelkalk, the new red or variegated 

 sandstone (gres bigarre, bunter 

 sandstein), the zechstein or mag- 

 nesian limestone, and the red con- 

 glomerate (rothe todte liegende, 

 gres rouge). The whole is con- 

 sidered as a mass of conglomerates, 

 sandstones, and marls, generally of 



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