Mr. Hutton's Notes on the New Red Sandstone of Durham. 349 



skill and professional experience of my friend, Mr. Francis 

 Forster, along the whole of the line. 



The beds composing the lower new red sandstone vary con- 

 siderably both in mineral character and thickness : one great 

 division may, however, be satisfactorily established, viz. an 

 upper and a lower bed. 



„The upper bed is generally a running sand, occasionally it may 

 be considered as a sandstone, but it never possesses coherence 

 enough to be of use as a building material; it has interspersed 

 through it, rounded grains of white quartz, which occur very 

 irregularly, but are often arranged in lines parallel to the 

 planes of stratification ; the prevailing colour is a very light 

 buff. Between this and the lower bed, which is more con- 

 solidated, and of a red colour, the division is generally well 

 marked, but sometimes the two pass into each other insen- 

 sibly, the sand gradually changing its hue, becoming com- 

 pact and micaceous. The colour of the lower stratum is a 

 character which varies exceedingly ; it is at all times, more 

 or less, red, sometimes purple ; but almost every quarry fur- 

 nishes beds, which, when taken alone, have little in their 

 aspect to distinguish them from a common coal grit; some- 

 times it is light yellow, or nearly white, with zones or bands 

 of deep red, and frequently the colouring matter is in veins 

 and spots. The characteristic colour of this rock appears to 

 arise from oxide of iron disseminated through it, but this is 

 frequently united with a clayey matter, forming nodules of 

 " ruddle," which are irregularly embedded in the stone. The 

 state in which iron exists in this formation is different from 

 that of the coal measures generally; — in no instance were we 

 able to discover a nodule of clay ironstone, in the different 

 beds composing it. The texture of the lower bed also varies 

 considerably, it being sometimes of a fine even grain, and 

 compact enough to be worked as a building stone; at other 

 times it is coarse and uneven, from the quantity and size of 

 the embedded grains and nodules of quartz. It is always mi- 

 caceous, and some of its beds so much so, as to split into thin 

 laminae of a bright red colour, which are very prone to de- 

 composition. 



A conspicuous character of this lower stratum is, the false 

 bedding of the stone, which may be seen in every quarry; but, 

 perhaps, the best character of all to distinguish it from a coal 

 grit, is the total absence of vegetable organic remains. 



This sandstone, in the course of its outcrop, follows gene- 

 rally that of the magnesian limestone, but occasionally pro- 

 jects beyond, where it is hard and of considerable thickness. 



For the sake of perspicuity in the following remarks, we 



shall 



