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deposited beds of the series traces of vegetable life are to be found, and although, 

 of course, it is irapossible to say with certainty what forms of such life existed on 

 the lands round whose shores pla5'ed the waves of the Old Eed seas, yet there is no 

 evidence of any such luxuriance of magnificent flora as in a subsequent period 

 produced by its decay our present beds of Coal. 



If you will look at this map you will see that the formation extends from 

 Bridgnorth on the north, down to Cardiflf on the south, and into Pembrokeshire 

 on the S.W. ; from the Malverns on the east, to the hills of Brecon and 

 Caermarthenshire on the west. It is developed in Scotland, Russia, and 

 Belgium ; and in North and South Devon, and Cornwall, rocks of a similar age, 

 as appears from their fossil contents, constitute what is called, for the sake of 

 distinction, the Devonian grouj). With neither of these localities, however, have 

 I at present any concern, confining myself to the plan I here shew yon. On the 

 western side of the area, coloured here dark red, you will notice several detaclied 

 portions, which are called "outliers" in geologic phrase, and whose existence 

 I will ask you to bear in mind. The most northerly of these occurs not 

 far from Shrewsbury, on the Long Mountain. There is another on Clun 

 Forest, and another to the west nearer Newtown, and there are otliers near 

 Knighton, near Presteign, and again near the Staiiner Rocks and Old Radnor. 

 Further, you will observe that the dark red flows, as it were, round a small 

 patch of dark green, near Ludlow, round a larger near Monmouth, and skirts a 

 larger still in Glamorganshire. These represent the Carboniferous, nr coal bearing, 

 rocks on the Clee Hill, the coalfield of the Forest of Dean, and the important 

 coalfield of South Wale.s, respectively : so that you may consider of the lavender 

 coloured portion, which denotes rocks of Silurian age, as being laid down first ; 

 of the dark red, or Old Red Sandstone, as Ijein;,' laid down over tlieni ; and of tho 

 green, or Carboniferous system, as being laid down over the Old Red. 



Let us try to picture to (jurselves this process of deposition of which I have 

 spoken, for, of course, you will be prepared to understand that these great masses 

 of what was originally loose sand, or loose gravels, were brought into their present 

 positions by the agency of water. Imagine, therefore, a large expanse of shallow 

 water. The earliest beds, as they are to be seen near Ludlow, Ledbxiry, and 

 Kington, give evidence of this shallowness. Whether that water was salt or fresh 

 is still a debated question. I will not trouble you with the scientific pros and cons 

 for either view ; it will be enough to state that tlie most recent authority holds 

 that, at all events in the early day of the series, when the lowest beds were laid 

 down, the deposition took place either in a very broad estuary of some river, or where 

 at least the water of the sea had access to it. Then, by the gradual sinking of the 

 ground (such as is ever going on on the surface of the earth somewhere), the depth 

 of this inland sea or lake increases. The waters of the rivers that feed it bring 

 down the detritus, the spoil, of existing rocks of what was the dry ground. 

 Naturally this is laid down on the bottom in this kind of order : the heavier 

 gravel and shingle nearer the shore, the sand, next in weight, farther out, the 

 lighter particles of mud floating in the streams farther out still. So you have 

 accounted for, the conglomerates, or pudding-stones, formed of the gravel ; the 



