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Looking at the whole system, both in point of time and composition, we are 

 positively reminded of marine conditions — of sea shores whose sands formed sand- 

 stones, and of beaches whose gravel was consolidated into conglomerates and 

 pudding-stone — of receding tides that produced ripple-marks, and of showers 

 that left their impressions on the half-diied silt of muddy estuaries. My collection 

 has several slabs with ripple marks, and stones showing spots of rain which fell 

 countless ages before even the Coal Measures were deposited. The reddish colour 

 which pervades the whole strata shows that the waters of deposit must have been 

 largely impregnated with iron, in all probability derived from the earlier granitic 

 and metamorphic rocks, whose degradation supplied the sands and gravel of the 

 system. If, on the other hand, we investigate the fossil remains, we are reminded 

 of placid waters where zoophites and mollusca swarmed in profusion ; of disturb- 

 ances which entombed whole shoals of fishes in marine sediment ; of marshes and 

 river-banks which gave birtli to a scanty growth of ferns, reeds, and rush-like 

 vegetables ; and of sedgy margins where, perhaps, a few lowly reptiles enjoyed 

 the necessary conditions of amphibious existence. 



The Old Red Sandstone imbeds obscure plant-remains, apparently of aquatic 

 origin, and numerous fishes and Crustacea, but no trace of coral, or unquestionably 

 marine organism, has been detected, so that, as far, as fossil evidence goes, the Old 

 Red of Herefordshire and Scotland may be of fresh water origin, but the more 

 general belief is that portions of it were deposited in Lagoons of great area. On 

 the other hand, while plant-life is almost wanting in Devonian strata, they abound 

 in corals, echinoderms, trilobites, and mollusca of undoubtedly marine habitat — 

 thus proving their deposition under oceanic conditions. 



The Old Red Sandstone passes insensibly in places into the Silurian Rocks 

 below. The passage beds called Downton Sandstones and Ledbury Shales have 

 been assumed to belong as much to one system as to the other, but my experience 

 of the latter formation enables me to say that it partakes much more of the Old 

 Red than of the Silurian Rocks. 



In order to gain some idea of the importance of this great geological system, 

 it will be well to consider the large area which it occupies. It extends from the 

 neighbourhood of Bridgnorth past Ludlow, Tenbury, Leominster, and Hereford, 

 and practically embraces the whole of that county and very much of Monmouth- 

 shire. It nearly surrounds the coal fields of South Wales, and surrounds entirely 

 those of the Forest of Dean, which is an outlier of the former, and extends away 

 due west into Pembrokeshire and to Milford Haven, with a slight break only 

 near to the latter place. In travelling to-day from Ledbury to this spot I have 

 never been off the Old Red. The maximum thickness may be taken at 10,000 or 

 11,000 feet, but in many places it would not exceed half that estimate. Examples 

 of the passage of the Old Red into the Silurian may be seen between the town of 

 Ludlow and the Glee Hills, and thence all along the eastern edge of the Upper 

 Silurian Rocks in Hereford, Radnor, and Brecon ; in many places round the 

 outside of the valley of Woolhope, but nowhere better, or indeed as well as at 

 Ledbury, where the whole of the Passage Beds are exposed on the surface. And 

 perhaps there is no other spot in the whole world where the same advantages 



