78 REPORT—1874. 
Cretaceous 23)... 58% Upper Chalk with Flints. feet. 
Triassic ti... Ra alee iets Upper Bunter Sandstone. 
( Middle Coal-measures.—Consisting of sandstones 
with soft shales and very thick beds of fire-clay, 
| ironstones, and many coal-seams, often thick. 
] Lingula squamiformis and Anthracosia, also fish- 
) 
Coal-measures, probably remaips very abundant. Ferns, &c....... about 930 
1930 feet. Lower Coal-measures.—Chiefly hard sandstones and 
erits, sandstone slate, and hard shales, with but 
few coal-seams orironstones. Plantsvery abundant. 
Gontatites and Lingula occasionally. Fish-remains 
| rather scarce. (? Gannister-beds.) .... probably 1000 
Milistone-grit. ........ Coarse grits and sandstones ............ robably 200 
Voredale Shales ...... Black calcareous and non-caleareous shales with 
bands of limestone, sandstone, and clay-ironstone 
fhodaless (eis. wT. oe Gh DOR eee 600 
Upper Limestone .... Crystalline and marly limestones } 
with sandstone bands.......... | 
SEL Doorn rca tecture Impure limestones, shales, and sand- { In all perhaps 
BONER PiU ih Rs API Bae ( about . 
Lower Limestone .... Sandy limestones, shales, sand- | 
stone, and dolomite .......... J 
The author haying explained his reasons for adopting the above classification 
and thicknesses, went on to describe the coal-fields in detail, commencing with the 
Dungannon coal-field, which extends from near Dungannon to beyond Coal- 
island; and which, though of small area, is extraordinarily rich in coal-seams, for 
it contains from 22-24 coal-beds, at least 13 of which are workable, while 17, 
containing about 42 feet of workable coal, lie in 300 yards of strata. They are all 
highly bituminous coals, and two of them contain valuable bands of cannel. Ina 
series of analyses of these coals the author found the amount of volatile matter 
ranged from 37°5 to 47°8 per cent., so that all are highly adapted for gas manu- 
facture. With all this, firedamp is almost unknown. 
In the upper measures there are important deposits of fire-clay, which are 
extensively used in brick- and tile-works. The ironstones are not sufficiently 
abundant perhaps to work; but the author found the amount of metallic iron in 
six specimens to range from 21°70 to 35°50 per cent. As to the resources, he 
- considered that there must be from 30-40 millions of tons of coal yet untouched, 
only counting the coals of a yard thick and upwards, and including the smaller 
coals 9 millions more. 
This coal-field is bounded on the north-west by a large fault, which brings down 
the Coal-measures on the south against the Calp and Lower Limestone. It must 
therefore have a downthrow of more than 2000 feet. 
North of it the limestone is found covered with triassic strata, without any 
intervening Coal-measures for 33 miles, when a small trough of the Middle Coal- 
measures containing the four upper Coalisland coals is found, inlaid by means of 
several faults on the north, south, and west, amongst the other rocks. This coal- 
field* is but 23 miles long by } mile wide, yet must contain the whole series of 
Middle and Lower Coal-measures, Millstone-grit, and Yoredale beds. However, the 
upper beds are nearly worked out; and supposing all the others to exist, the supply 
can hardly be more than about 800,000 tons. The coal-field may still stretch away 
to the eastward under the newer strata. 
A little to the north of this coal-field a little patch of Permian Limestone is found 
resting immediately on the Carboniferous Limestone. 
The author proceeded to explain when and how the two coal-fields became 
isolated from each other, and why in the immediate vicinity of these thick Coal- 
measures the Permian or Trias are found reposing directly on the Limestone. At 
the close of the Carboniferous period those rocks were forced into a series of 
flexures or folds ranging east and west, owing to the influence of forces acting from 
* The Annaghone Coal-field. 
