82 Reviews — Phillips' Geology of Oxford. 



islands branching out in a wide expanse of ocean ; tlie Cotswolds 

 broken up into many digitated masses ; the Thames basin confluent 

 with the Avon of Wilts and the Avon of Warwick ; no limit to the 

 sea on the eastward ; still the straits of the chalk remain at Pang- 

 bourn ; islets of the Oolite near Oxford ; and other straits appear, 

 especially on the Evenlode and the Cher well, through which a com- 

 munication is opened to the great midland sea which reaches to the 

 hills of Lincolnshire, Derbyshire, and Shropshire. More than half 

 the area of land in the Oxford district is now submerged." Thirdly, 

 submerged " to 1000 feet and nothing of land remains but the higher 

 peaks of the Malvern Hills, Cleeve near Cheltenham, and Broadway 

 near Evesham. At intervals during the depression from 500 to 1000 

 feet, the straits of Evenlode and Cherwell might admit ice-rafts in 

 abundance from the northern seas, and allow of violent wave-action 

 on the parts of the land successively brought to the condition of sea- 

 bed. Thus may the red pebbles of Warwickshire have been trans- 

 ported to the vale of the Thames, and many important effects of 

 watery violence occasioned. The events here sketched have really 

 occurred ; the sea-line has been changed in the manner stated, in a 

 comparatively late part of geological time, as it had often been 

 changed before." . . . . " There is no evidence of this being a cata- 

 clysmic process, but much reason to treat it as a gradual subsidence 



and a gradual resurgence of the land." " Both while rising 



and while falling, the water hammered against the shores and dredged 

 along the channels ; wasting the surface, reducing the heights, 

 digging out the valleys, and spreading out detritus over submarine 

 plains." 



"Following continually the retiring sea, rivers often swept away 

 the traces of its action, or covered them with fresh deposits. Atmo- 

 spheric vicissitudes, rains and snows, heat and cold, disintegrated the 

 rocks ; carbonic acid aided in dissolving them ; new phenomena 

 replaced the older ones ; new features were impressed on every hill 

 and every hollow ; and thus our land-surface, as we see it, exhibits 

 in every part the modifications produced by what may be called the 

 ' ordinary action ' of daily causes, these being superimposed on 

 broader aAd greater features generated by elevation and depression 

 on a great scale, accompanied by powerful waves and strong currents 

 of the sea." (p. 46.) 



Fourteen chapters are devoted to the stratigraphical sequence of 

 the rock-formations of the area. Each successive period is traced out 

 mineralogically and pal^ontologically, and actual illustrative sections 

 are referred to in every case, with complete lists as well as plates 

 and woodcut illustrations of the fossils. Commencing with the 

 Palaeozoic rocks. Prof. Phillips shows that " the oldest stratified 

 rocks of England, probably older than any in Wales, perhaps as old 

 as any in Scotland, are found in the Malvern hills, within two hours 

 of Oxford. These hills rise from the valley of the Severn, in a soli- 

 tary ridge, to which there is really nothing very similar in the 

 British Islands ; the nearest analogues, by geological position and 

 mineral character, being perhaps the felspathic rock-groups of the 



