288 ON THE PARTICULAR ORDER OF 



Micaceous Schist 

 Chlorite Schist 

 Limestone 

 Argillaceous Schist 

 Gneiss, 



In this particular case, the alternations amount 

 to some thousands. 



To proceed now to the secondary strata, it will'be 

 best to give the order of succession in England, and 

 in an entire state, as it is conceived to be determined 

 by the numerous geologists who have bestowed great 

 labour and care on this department. The groupings 

 of the beds, or the divisions into scries, must stand 

 on the authority or opinions of observers whose ability 

 and industry are admitted, and who are too well 

 known to need mention here. 



On the Succession of Strata in England and 

 Scotland. 



The lowest bed of the secondary strata of England, 

 is the old red sandstone, being the first of the secon- 

 dary rocks in the artificial classification. It must not 

 however be considered as a simple rock ; since, be- 

 sides the conglomerate which is essential to it, it 

 sometimes contains shales and limestone, and, occa- 

 sionally, coal. 



The next bed in the order upwards, is a limestone 

 containing a few fossil remains, and known by the 

 name of mountain and of carboniferous limestones. 

 In this rock also, there are found smaller beds of 

 shale, and, occasionally, of sandstone ; much more 

 rarely, of coal. A sandstone called the Millstone 

 grit follows in some places ; but it seems to be one of 

 the most limited of these leading strata, while it does 

 not appear very satisfactorily proved that it does not 

 form a part of the coal series. 



