SECONDARY ROCKS— GENERAL RELATIONS. 17 



of strata, are, if viewed with the extent of the globe, only 

 local. In the Lothians the divisions of old red sandstone, 

 and mountain limestone, are unnatural ; for strata which, 

 in one locality, might, from their relations to others, be 

 considered as the old red sandstone, are, in another, found 

 to occupy a position which renders this impossible. If these 

 sandstones are found both above and below the mountain 

 limestone, and are frequently seen to alternate with it on 

 the large and small scale, it is evident that they form one 

 deposit ; that the causes which produced them were not 

 interrupted by paroxysms of violence. In the Lothians 

 and in Fife, there are many points which evince that the old 

 red sandstone, mountain limestone, and coal formation, can- 

 not, as developed in these districts, naturally be separated. 

 Professor Jameson, in his Mineralogical Account of Dum- 

 fries-shire, p. 165, enumerates several localities in the Lo- 

 thians and in Germany, where red sandstone is found in- 

 timately connected with the white sandstone series. In re- 

 gard to the occurrence of red and brown sandstone, the 

 Professor states, " 1st, In lower Silesia, nearly the whole of 

 the coal-field is composed of reddish-brown and cochineal 

 coloured sandstone, with which great beds of coal alternate. 

 2dly, In the coal-field of Mid-Lothian we ha\e the follow- 

 ing instances of similar coloured sandstone occurring in the 

 coal formation : a. In Dryden Water, near Loanhead, there 

 are several beds of reddish -brown coloured sandstone, ac- 

 companied by similar coloured ironstone in the coal for- 

 mation, b. Near Mr Cameron's paper-mills, on the banks 

 of the Esk, there are thick beds of reddish-coloured sand- 

 stone, that evidently belong to the coal formation, and the 

 same rock continues in the direction of the river, forming 

 the picturesque cliff's of Hawthornden and Roslin, and ex- 

 tends even to Auchindinny Bridge, c. Immediately behind 

 themanse of Collinton there is a beautiful section of the 

 vol. vii. b 



