61 



Lowermost, we have the Skiddaw Slate group, a great thickness 

 (some 8,000 to 10,000 feet) of old muddy and sandy deposits, indicating 

 general shallow water conditions, and containing remains of marine 

 organisms. Such a sequence of beds indicates a continued subsidence of 

 the sea bottom, thus allowing the accumulation of so gi'eat a thickness of 

 shallow-water deposits. It is quite impossible to estimate the length of 

 this period — as impossible as it is to conceive of the distance separating 

 us from our central luminary. But at last the I'ecords of this first volume 

 of our geologic history cease or pass upwards into those of volume two. It 

 would seem that those mysterioiis forces from below began to seek some 

 outlet, and a line of weakness being found, a volcanic vent was opened 

 out. The earlier eruptions were clearly sub-marine in character, for we 

 find muddy deposits interstratifled with beds of volcanic lava and ash, 

 but soon the shallow sea became filled iip, or a moderate elevation helped 

 to convert the sub-marine volcanoes into sub-aerial ones. The great series 

 of volcanic deposits now piled up above the Skiddaw Slates, and forming 

 our second volume, maybe estimated at 10,000 or 12,000 feet, but as we 

 know that volcanic activity is very variable in its nature, it is not easy 

 to form an idea of the duration of the period, which, however, may have 

 been far shorter than the preceding. 



We next come upon a gap in our records ; a long j^eriod of time 

 ela^Dses, during which no volume is inscribed, but, on the contrary, por. 

 tions of the previoiis records destroyed by denudation, so that when the 

 volcanic tract of land has subsided fairly beneath the sea-level, the succeed- 

 ing marine deposits are laid down iipon an irregular and denuded surface. 

 These marine deposits consist of the Coniston Limestone and Upper 

 Silurian grits and slates, the whole having, according to Mr. Aveline's 

 estimate in the Kendal district, a thickness of no less than 14,000 feet. ■ 

 Once more, then, we find the evidence of the continued slow subsidence 

 of the sea bed sufficient to allow of the accumulation of this great thick- 

 ness of deposits. The fourth volume (the third being wanting) of our 

 history may be formed of very similar materials to those comi^osing our 

 first, but the nature of the writing has in great part changed, just as the 

 characters used in a fourth century manuscript may be distinct from, and 



