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The Downton Sandstone has been generally Included In the Silurian rock, end on 

 the ordinance geological maps it is so coloured ; but it is to be hoped that on the next 

 revision of the maps these distinctive beds will be shown by a colour of their own. 



The Downton Sandstone is lithologically a true transition formation, and cannot 

 be classed as a whole with the Silarian or Old Red Sandstone. It is not composed of 

 the denudation of the adjacent Ludlow rocks, but is probably formed from the destruc- 

 tion or disentegration of the Caradoc Sandstone, which it greatly resembles. 



These passage beds are here, according to Murchison, only 40 to 50 feet in thickness. 

 Mr. Banks has again rendered good service to geology by detecting in them a series 

 of fossils which prove beyond all doubt, that fossils in themselves are not so distinc- 

 tively characteristic of particular formations as they were before supposed to be. 

 I believe the Downton Sandstone contains the oldest recognisable vegetation yet found 

 in England and Wales ; but it does not at all follow from this negative evidence that 

 there was not a rich flora at the time of its deposition, for in the old Silarian locks In 

 Scotland traces of land plants have t>een discovered. 



The Downton Sandstone is well developed in the band at Ludlow. Is the pub- 

 lished geological section running across that town, it is represented from my own actual 

 observations to be 80 feet in thickness. Few organic remains occur there, the principal 

 ones being the flshes PteraspU and Cephalaspis, with the crustaceans EurypUrus, 

 Pterygotus, and the small Beyricha. 



On examining the district immediately around Old Badnor yon will find that 

 there is a line of Fault running from the West side of Stanner hill, in a north-easterly 

 direction, to Nash Scar. On the east side of this line of Fault the Wenlock Limestone 

 and Upper Llandovery rock are thrown up. On the western side of the Fault appears 

 the Old Red Sandstone of Badnor wood. This Fault was caused by the force which 

 caused the protrusion of the Stanner rocks, and the upheaval of the Wenlock Limestone 

 of Nash Scar. 



There is also another Fault running past the east side of Old Badnor hill, nearly 

 parallel with the Fault already alluded to, and about half a mile from It. This line of 

 Fault was caused when the Syenitic granite of Hunter hUl was thrown up, and the 

 Wenlock Limestone and Llandovery rock of Old Badnor appeared. 



The fiat district north-west of Old Badnor and around Harpton Court is on the 

 Wenlock Shale, where it is very much obscured with a deep covering of gravel. Badnor 

 Forest belongs to the Upper Ludlow formation, and the country south-east of Llandegley 

 is on the Llandilo Flags and Shales. 



The amorphous, massive, and crystalline condition of the Wenlock Limestone at 

 Nash Scar and Old Badnor was caused by the action of heat issuing along a line of 

 fissure, which, emitting the igni ou? rocks of Stanner and Hunter-hill, fused the strata 

 into huge amorphous masses, and left films of Serpentine on the faces and joints of the 

 altered limestone. 



On the western slope of Old Badnor hill in the Wenlock Limestone casts of the 

 Pentamerus ob'onyus and other f ssils may be found. 



Looking to the north-west of Old Badnor, all the land visible was above the level 

 of the sea when Herefordshire and the other parts of England eastwards were below it. 

 Possibly at that time Wales, with the Isle of Man and Ireland, may have formed a 

 series of islandb in the ocean . 



From the distribution of land and water, and from astronomical causes, there is 

 no doubt but that the climate of this diftrict was much more severe at one time than 

 at present, for we have abundant evidence of glacial action in many places. I may 



