Rev. J. Clifton Ward—Greology of the Isle of Man. 3 
The rock occurs in four forms. 1. As a coarse thick-bedded 
sandstone or grit, slightly conglomeratic in parts. 2. As more or 
less thickly-bedded flags of a grey colour within but often irony 
on the outside. 3. As black slate frequently flaggy in character, 
and occasionally cleaved. 4. As soft black shale, not unlike coal- 
measure shales. All these forms also recur in the Lake District 
Skiddaw Slate group. No. 1 is perhaps best seen at St. Ann’s 
Head, four miles south of Douglas. No. 2 is well represented at 
Douglas, and furnishes most of the building material of the town. 
No. 5 may be well seen about South Barrule slate quarries, where 
cleavage is developed, and on Spanish Head, where the black flags, 
lying almost flat. are quarried for gate posts. No. 4 occurs in the 
upper parts of Glen Meay (west of South Barrule), and other places, 
It would be unsafe to offer any decided opinion upon the divisions 
of the Skiddaw Slate in the island without having made a detailed 
survey of the whole, and still more so to point to certain parts as 
the equivalents of Lake District divisions. That gritty beds 
occurring at St. Ann’s Head and on Carn Gerjoil (marked in round 
dot pattern on the map) resemble on the whole the Skiddaw or 
Arenig Grit previously alluded to, is but imperfect evidence at the 
best. This much is however to be said in favour of their identity, 
that the slates of the Snae Fell range, extending from N. Barrule, 
through Snae Fell, to Greeba and S. Barrule, have a general north- 
westerly dip, and much resemble the black slates of the Cumberland 
Skiddaw. The sandy and gritty beds of St. Ann’s Head dip east- 
wards, while those on Carn Gerjoil dip westwards. It may be that 
they respectively represent the two sides of an anticlinal which 
runs from a little south of Ramsey to a little west of Douglas. On 
the other hand, it is possible that some large fault runs through the 
nearly east and west central valley, between Douglas and Peel. 
Gritty bands again occur south of Peel. Prof. Nicholson also 
describes a quartz rock with pebbles three miles west of Ramsey 
dipping to the north-west, and containing black shale bands, and a 
little south of Crosby station I observed a thick bed of quartzite 
dipping west under black shale. Very likely, indeed, there are gritty 
beds on several different horizons, and, indeed, on the east of the 
island especially, the beds appear much more sandy than is the 
_ general character of the series in the Lake District. 
A broken line from south of Ramsey to near Douglas indicates the 
general direction of a marked anticlinal ; and a dotted line from the 
south of Laxey to Douglas, a marked synclinal. An anticlinal 
} 
again appears running through the harbour of Port Erin, and on the 
north side of this, “especially at Bradda Head, the rocks are 
beautifully contorted, though showing a general north-west dip; on 
the south side, haa cuee abort Spanish Head, the beds are almost 
horizontal or dip slightly seawards, giving rise to large slips and 
broken ground known by the name of the chasms. With the chance 
of a large fault between Douglas and Peel it is hard to parallel the 
rocks north and south of Port Erin with any particular portions of 
' those in the north of the island. The strike of the black flaggy 
rs 
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