Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/68

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in Kearsdale, the country begins to assume a more majestic form, and rising into a mountain range it constitutes the central ridge that traverses the island. Cross Fell, situated near the junction of the five northern counties, may be considered as the summit of the whole chain. Its latitude is 54° 42′ .05″ north, and its distance I from the eastern coast 55 miles. Its height is 2901 feet, and it is therefore one of the highest mountains in England.[1]

The strata in the southern and mountainous part of this district dip on an average 2° 15′, or 1 yard in 27 to the cast 35° south, so that on crossing the range from east to west they will be seen cropping out one after the other, and forming parallel ridges extending from the south-west to the north-east. In this part of the mining field considerable uniformity may be observed amongst the sills. Thus the sections at Allenheads, Coal cleugh, Aldstone moor, and in Weardale, are allied to those above Blanchland on the Derwent, and agree very closely with one another: if therefore those of Hely field, Aldstone moor, Dufton Fell, and its sequel, be taken in succession, they will give no very inaccurate representation of the prevailing series of beds in this part of the district, and the total thickness of these beds thus obtained will be 2717 feet. In the less elevated tracts of Northumberland this uniformity is no longer preserved, and it is only a very general resemblance that the measures then bear to those of the south. On the banks of the Tweed the disagreement becomes more evident, so that it may even be doubted whether the rocks of that valley are correctly placed among the lead mine measures.

  1. Height of Cross Fell by geometric measurement 2901 feet
    ─────── Helvellin 3055
    ─────── Skiddaw 3022
    ─────── Saddleback 2787