IJbMAIN V. CALCAREOUS. 



months, was covered with a glassy crust of a sili- 

 ceous nature, arising from some lapideous juice, 

 which remains, as before observed, among the 

 secrets of nature ; because stones have never been 

 analysed in their original state. 



Even Mr. Kirwan has little enlarged upon the 

 calcareous sandstones. Mr. Jameson has, as 

 usual, employed much labour in illustrating the 

 different formations ; but he has not drawn a pre- 

 cise line of distinction between the different kinds ; 

 as it is probable, however, that his third forma- 

 tion is chiefly a calcareous glutenite, the fallowing 

 curious observations well deserve a place here. 

 la columns. " No rock presents a greater variety of exter- 

 nal appearance than this sandstone. Its valleys 

 are deep, rocky, and romantic ; its hills conical, 

 steep, and cliffy ; and it often presents grand co- 

 lossal pillars and masses, which, from their num- 

 ber and variety of their shape, form most striking 

 rocky scenes. These hills, pillars, and masses, 

 often reach a considerable height ; but their sum- 

 mits are all nearly on the same level. One of the 

 most striking appearances of this kind is at Aders- 

 bach, in Bohemia. There we observe numberless 

 cones, pyramids, and pillars, sometimes isolated, 

 sometimes joined together, and from two to three 

 hundred feet high, spreading over a considerable 

 tract of country. In other places, caverns or 



