152 



surface, and in the luxuriant growth of its timber, closely resem- 

 bles in many places the old red sandstone of Herefordshire, lies in 

 general, sometimes conformably, sometimes unconformably, upon 

 coal-measures, and even contains occasionally beds of that sub- 

 stance. But in the neighbourhood of Shrewsbury, and also at 

 Tasley and Coughley near Bridgnorth, Mr. Murchison has shown 

 that this lower red sandstone overlies unconformably and passes 

 down into a zone of coal-measures containing a peculiar fresh-water 

 limestone. The great coal-beds of Brozelej^ and Coalbrook Dale 

 are wrought beneath it. 



I had occasion myself to observe during the last summer, in the 

 neighbourhood of Nuneaton in Warwickshire, a limestone similar in 

 aspect, lying under a two-foot bed of sulphureous coal. The lime- 

 stone is about fourteen inches in thickness, and exhibits veins of 

 galena in calcareous spar. At the first pit I visited there was but 

 one bed of limestone, but at another on the same estate is a second 

 bed which also contains galena, and on its surface numerous impres- 

 sions of plants. The interval between the two beds is occupied by 

 a sandstone not unlike the Pennant rock in appearance, and what 

 is here called a chance coal. Immediately beneath the lower one 

 is another bed of coal four feet in thickness. 



In three papers which Mr. Conybeare has lately published on the 

 relations ofour principal coal-fields*, he considers it probable that coal 

 will be discovered hereafter in many districts as yet unexplored. He 

 dwells upon our uncertainty as to the boundary of the carboniferous 

 beds in the midland counties, and recommends that a survey should 

 be undertaken expressly with a view^ to determine this problem : 

 " It is little to the credit," he observes, " of a nation like ours, so pe- 

 culiarly dependent on this branch of her mineral resources, that we 

 continue to acquiesce in a state of ignorance so easily removed. 

 We here see a strong instance of our want of a regular school of 

 mining, such as is possessed by many countries." 



Mr. Elias Hall has published a geological map of Lancashire, a 

 county hitherto comparatively neglected, and, I am sorry to add, 

 very indifl'erently represented in all the geological maps of England. 

 Mr. Hall is entitled to great praise for his intrepidity and perseve- 

 rance; had he not possessed these qualities in an eminent degree, 

 he never would have entered, as it were alone and single-handed, 

 on so irksome and laborious an investigation. That the work i.s in 

 many respects imperfect must be admitted, but considering the ap- 

 parent disproportion of his means to his end, it is surprising that the 

 author should have achieved so much : what he has left incomplete 

 or inaccurate will be readily supplied and corrected by the supple- 

 mental labours of more fortunate observers, when the physical fea- 

 tures of this extensive tract shall have been accurately delineated by 

 the Ordnance Department. 



For a detailed account of the carboniferous tracts in Salop and 



* Lond. and Edinb. Phil. Mag. and Journ. of Science, vol. iv. pp. 161 and 

 346, vol. V. p. 44. 



