430 J. Prestwich, Esq., on the 



and at another pit, a stratum of sandstone may be subdivided into beds, ac- 

 cording- to the compactness of the different portions. When two beds of coal 

 are separated by a layer of shale from only two to twelve inches, the layers 

 are frequently omitted*. 



This fact will readily be seen by an inspection of the shaft sections (see Ap- 

 pendix). The discrepancy from this and other causes is sometimes so great, that 

 were it not for the Penneystone, clod coal, best coal, and one or two more beds, 

 which serve as landmarks throughout the whole field, it would be difficult 

 to recognize the connexion between the Donnington district and the Ma- 



* As the colliers' names are retained in the shaft sections, an explanation of the most technical 

 ones is necessary. 

 Local Names. 



Bannock A slipperish, brownish gray clay. 



Bass Bituminous slate clay. 



Binds Fissile sandstone ; sometimes a slate clay. 



Calaminker Mottled clay — generally red and yellow. 



Garble Shivery sandstones. 



Clod Shale ; aspect dull and earthy. 



Clunch Clay, shale and marl ; unctuous, smooth and shining. 



Flint Compact sandstone— freestone. 



Heaving Earth A clay which absorbs moisture, and swells by exposure to the atmosphere. 



Linseed Earth A fine, indurated, gray clay — generally a fire clay — very frequently con- 

 tains a few ironstone nodules. 



Measure A term applied to all the workable strata, more particularly to the iron- 

 stone strata. 



Pitcher Bass Very bituminous slate clay. 



Pitchy Rock Rock impregnated with petroleum. 



Pounstone A stratum (generally of indurated clay) underlying a seam of coal. 



Pricking The thin layer of shale or clay in which the workmen undermine the coal 



or ironstone. 



Quoice Neck A shale which, when first exposed, exhibits shining and somewhat iri- 

 descent surfaces. 



RilifF Shivery sandstones. 



Rotch Hard mixed sandstone. 



Slums. . , Coaly shale or clay. 



Tator Butt Fragile sandstone. 



Espley Rock . . 



Peldon Pebbly. 

 Rough Rock. . . 

 Pebbly Rock . . 

 Pimp Rock... . 

 Bull Rock 



► Conglomeratic beds, of various degrees of compactness and coarseness. 



{The formation upon which the coal-measures repose, and ceases, or dies 

 out. Thus, at Madeley it is the Lower Ludlow Rock ; at Lightmoor 

 the Wenlock Shale, &c. 



