86 



Another point dwelt upon, perhaps still more curious, and which 

 also requires the consideration of the chemist, is, that wherever 

 igneous rock is present in the neighbourhood of beds of coal, and 

 yet separated from them by an intervening substance, which has. 

 prevented their being injured by intensity of heat, the coal is fre- 

 quently what is called " brighter and more bituminous ! " 



With such facts before them, the authors of this report are aware, 

 that other agencies than those of mere heat, are required to account 

 for the production of iron concretions and the crystalline struc- 

 ture of coal; but whilst they think, that electric and magnetic cur- 

 rents must also have operated in bringing about some of the results, 

 they are convinced that the presence of igneous matter, often ex- 

 tended laterally in the form of vast beds, must have had a great 

 share in the production of such phsenomena. Having myself taken 

 no little interest in the formation of tlie Dudley and Midland Geo- 

 logical Society*, I hail this report upon the physical condition of 

 the subterranean masses of that tract as worthy of the approbation 

 of men of science in all countries; for the history of Dudley is that 

 of many regions of the earth, which have been penetrated by in- 

 trusive matter. 



. ,,,;;,,; i:-''mJSeCONDARY BrITISH RoCKS. 



New Ked''^andsto7ie. — Our knowledge of the structure and con- 

 tents of the uppermost member of the New Red Sandstone has 

 been considerably increased by the researches of Mr. Phillips and 

 the Ordnance Surveyors. In our Memoir of parts of Gloucester- 

 shire, Worcestershire and Warwickshire, Mr. H. Strickland and 

 myself pointed out the existence of a peculiar bed of sandstone sub- 

 ordinate to the marls underlying the Lias, and we were led, on ac- 

 count of the fishes and shells contained in it, as well as from the 

 footmarks of peculiar saurians and its geological position, to refer this 

 rock and the associated marls to the Keuper formation of Germany 

 and France. The more detailed researches of Mr. Phillips confirm 

 this view, and show that the sandstone is far more continuous than 

 was believed ; winding with remarkable sinuosities over large areas, 

 and characterized by peculiar fishes and other fossils. With such clear 

 types to guide them, the Ordnance surveyors will, I trust, be able, as 

 they move northwards, to show the exact line of separation between 

 this deposit of Keuper marl and sandstone, and the great masses of 

 inferior red and yellow sandstone, which extending from Warwick 

 northwards, occupy large portions of the central counties, and expand 

 into the great formation on the banks of the Mersey, so strikingly 

 characterized by the footmarks of the Cheirotherium. These lower 

 sandstones must, I contend, be placed on the parallel of the Bimter 

 Sandstein of the Continent, in M'hich similar impressions occur, and 

 can never be confounded with the upper marls and sandstone of the 

 true Keuper f. 



* See Address to the Dudley and Midland Counties Geological Society, 



1841. .. \ 



I Since this Address was read, I have been informed by my friend Dr,; 



