262 



THE GEOLOGIST. 



upper series. As a general rule, it is said that the lower, or Gannister 

 series, contains some of the best coking coals. It also contains the finest 

 flags and tile stones. It is the principal earth for making firebricks. 

 There are plenty of similar earths in the middle and upper series ; but it 

 would seem that those in the lower series produce bricks which stand greater 

 heat. Like the coals of the lower series, those of the lower portion of the 

 middle series are chiefly good coking coals ; and at the top, or upper por- 

 tion, swift or hot-burning coals are produced. The coals of the upper 

 series are nearly all hot swift-burning coals. Cannel or Parrot coal is 

 found in each of the three series, but the best is in the middle series. 



Commencing at Mossley, near Ashton-under-Lyne, the following section 

 of the lowest coals is met with : — 





yds. 



ft. 



in. 













0 



1 



5 





0 



0 



8 



Shale and sandstone . 



. . 29 



2 



4 



Shale 



0 



2 



0 





0 



1 



9 





. 0 



0 



9 



Earth 



0 



0 



2 





1 



0 



0 



Shale s 





0 



0 





3 



0 



0 



Shale 





0 



0 







0 



7 



The lowest of these three coals lies at a distance of about 326 yards below 

 the Gannister coal. The principal, or 1 foot 9 inch bed, is the one which 

 is being worked at the Victoria Colliery, at Mossley. The three seams 

 retain their character southwards to Early Bank, in Cheshire ; but north- 

 wards they do so for a short distance only, and, except in that immediate 

 neighbourhood, there is no place in Lancashire where coal-seams are so fully 

 developed so low down in the coal-field. 



A general section of the principal coal-seams of the lower series near 

 Hartshead is as follows : — 



yds. ft. in. 



Coal (40-yards mine) . . . ' 0 1 6 



Strata, with an inch of Coal . 34 0 0 



Coal, upper foot 0 1 0 



Strata 15 0 0 



Coal mountain, or f (Gannister) 0 1 10, 



Strata 10 0 0 



Coal, lower toot 0 0 6 



Strata 90 0 0 



Coal, yard (sand rock) ... 0 0 6 



Strata, about ISO 0 0 



And then the upper, or oue-foot five-inch coal, given on the preceding 

 section, at Mossley. 



At Crompton, near Oldham, the lower foot coal is called the half-yard 

 mine, and the Gannister coal is still called the " mountain mine." The upper 

 foot and the 40-yards coal are also still known by the same names. The 

 upper foot coal has there a large number of round nodules both in it and 

 upon it, and also a very large number of fossils, generally Goniatites and 

 Avicula-pectens. 



At Bamford and Ashworth, the 40-yards coal still retains its name, and 



