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If you look at the Ordnance map, you will see that the former of these is coloured 

 crimson and the latter scarlet, signifying that the former is a mass of green-stone, 

 and the latter of felspathic trap. Sir Roderic Murchison speaks of them as 

 composed of greenstone and syenite ; syenite being a rock in which the mineral 

 hornblende takes the place that mica occupies in the composition of granite. 

 Subsequent knowledge, however, seems to show that these eruptive masses are not 

 composed of such purely volcanic material alone. Dr. Callaway has included 

 them in the patient investigation which he bestowed on the Wrekin and the other 

 Shropshire rocks of the same apparent date of outburst as these. In a paper 

 read before the Geological Society in 1879, he describes the structure of these 

 rocks thus : — " Hanter Hill is composed of gabbro on the east side, dolerite — or 

 greenstone — at the summit. On its north-east slope is a small exposure of grey 

 granitoid rocks." Professor Bonney having examined this granitoid micro- 

 scopically, pronounces it an altered rock, and in general appearance similar to 

 rocks of the same character near St. David's. " Stanner rock," Dr. Callaway 

 proceeds, "contains similar gabbro and dolerite. In about the centre of the 

 ridge is a grey compact felstone. At the north-east end is a dark grey grit, with 

 obscure east and west bedding, and near it, to the south, is a quartzose breccia. 

 In the same locality is seen a grey granitoid rock, similar to the specimen at 

 Hanter Hill." Now in his examination of the Wrekin and Caradoc rocks. Dr. 

 Callaway has become persuaded that these rocks are composed of deposits of a 

 pre-Cambrian age— that is to say, of an age preceding that when the old rocks of 

 the Longmynd were formed — which have been thrust through the surface of later 

 overlying rock by the eruption of the molten greenstone. On each side of this 

 igneous axis, as he has observed it in Shropshire, he finds lines of fault. And he 

 finds, too, that the bedded tuffs and felspathic rocks which are on the surfaces of 

 the hills strike transversely to the general strike of the strata which are thrown ofiE 

 from the sides of the erupted masses. Hence he concludes that there underlay 

 all the series of rocks which we reckon from the Cambrian upwards, a regular 

 formation of earth crust of which the strike that the beds assumed was transverse 

 at varying angles to the strike of these latter. And that when the volcanic force 

 began to operate, the greenstone produced drove up wedges of this underlying 

 bedding through the cracks made by the faults above mentioned. Now he has 

 hesitation, he admits, in referring the composition of Stanner and Hanter Hill to 

 these pre-Cambrian times ; in other words, in expressing a definite conviction that 

 the Granitoids and Felstones and Breccia which I have spoken of as existing here 

 are the metamorphosed representatives of the old pre-Cambrian earth crust shoved 

 up from beneath, which he has identified to his own satisfaction and that of others 

 as appearing at the Wrekin and the Caradoc range. But you will observe that in 

 his description of the structure of this rock of Stanner, he speaks of a certain 

 "grey grit at the north-east end, with obscure E. and W. bedding," as if he 

 detected the phenomenon of that transverse strike of upheaved beds which are 

 indeed plainly to be seen at the other localities he mentions. I suppose that if 

 further research in this neighbourhood should prove the existence of definite 

 faulting on the eastern side of Stanner as well as on the western it would go far to 

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