HARDWICKE'S SCIENCE-GOSSIP. 



53 



logical surveyors the Elland flagrock and Greenmoor 

 rock. Underlying the flagrock in descending order, 

 there are about 120 feet of shale and raggy stone, 

 then the 80 yards band coal which is only about 

 6 inches in thickness, then about 100 feet of more 

 shales and rag, followed by the 48 yards band coal 

 of about 10 inches in thickness, then 36 feet of more 

 shales followed by the 36 yards band coal, having 

 3 to 4 feet of seat earth under it, which forms one 

 of the most valuable fire-clays in the neighbourhood. 

 Then follows about loo feet of more shales gradually 

 merging towards the base into fossiliferous marine 

 strata, then comes about 8 to 10 feet of shales highly 

 charged with calcareous nodular concretions, gene- 

 rally coated with pyrites, and containing a rich and 

 varied assortment of marine fossils such as Goniatites 

 Nautili, OrtkoceraSf Avicitlo-pcclcii, and many other 



lime, pyrites, calc-spar, and vegetable remains. 

 They are nearly always thickly coated with pyrites 

 and are often very difficult to break open, an ordinary 

 hammer being of little use for this purpose, and too 

 frequently the whole ball is one mass of pyrites. In 

 composition and external appearance they much re- 

 semble the nodular concretions which occur in the 

 marine strata above the coal, but there is a total 

 difference in their fossil contents. The coal balls 

 contain fossil plants exclusively, while the baum pots 

 contain marine shells and fish remains, and occa- 

 sionally fragments of the fossil pine, called Dadoxy- 

 lon, which have evidently been drifted into the sea 

 in which this bed was formed, from some neighbour- 

 ing land. 



The hard bed coal rests upon the very peculiar 

 rock called gannister, which varies in thickness from 



Fig. 38. — Enlarged section of beds i, 2, 

 and 3 of "Hard Bed." i. Mnrlne 

 beds with "Baum pots," containing 

 Goniatites Listeri, &c., Nautili, Or- 

 thoceja^, Aviculo-pecten, &c., also 

 occasionally fossil pine wood ( Dudoxy- 

 loni, showing structure ; 2. " Hard 

 Bed " with " coal balls." containing a 

 great variety of coal-plants, as I.rfit- 

 dodendro'i, Sigiilaria, &c. ; 3. Gan- 

 nister rock and seat earth. 





MILLSTONE GRIT 

 ROUGH R^CK 



Fig. 39- — Sec- 

 tion of Strata 

 in the neigh- 

 bourhood of 

 the " Hard 

 Bed " Coal. 



ANTl-lRACOSIA BEDS 

 SOFT BED/^ 

 COAL 



HA LI TAX 



35a 

 HCBBLE BROOK 



kinds of fossil shells and fish remains. Immediately 

 underlying the marine strata is the hard bed coal, 

 containing in many places those remarkable nodules 

 called coal balls. These coal balls are found in the 

 coal itself, and in some places the whole bed is 

 occupied by them with only a little admixture of 

 coal, but "generally they seem to be scattered through- 

 out the coal seam at irregular intervals. Some coal 

 pits yield them more abundantly than others. We 

 have traced them all round the outcrop of these 

 strata from Denholme in the north, by Halifax, 

 Elland, Huddersfield, Hepworth, to near I'enistone, 

 where they appear to approach their southern limits. 

 They are found also at about the same geological 

 horizoii on the Lancashire side of the Pennine chain, 

 in the neighbourhoods of Bacup, Todmorden, Roch- 

 dale, and notably about Oldham. The materials 

 composing the coal balls consist of carbonate of 



I foot 4 inches, in the neighbourhood of Halifax, to 

 3 feet in the neighbourhood of Penistone. Under- 

 lying the gannister there is a bed of seat earth, and 

 both seat earth and gannister are full of stigmarian 

 rootlets, while some of the best specimens of the 

 ordinary stigmarias are met with in the gannister rock. 

 About 75 feet below the hard bed coal, the soft bed 

 coal is met with, and midway between them occurs 

 another thin seam called the middle band coal ; 

 underlying it, there is a valuable bed of fire-clay, 

 which is extensively worked in this district. Mid- 

 way between the middle band and the soft bed coal, 

 there are three layers of shale which are literally 

 full of Anthracosia, separated by black shale contain- 

 ing Spirorbis carbonarius. The strata below the soft 

 bed coal contains nothing noteworthy in the Halifax 

 district, but in the neighbourhood of Huddersfield 

 occur what are called the soft bed flags, and under 



