68 -REPORT—1874, 
travelling British public which at one time or another makes the delightful pilgri- 
mage to the workshop of Vulcan and the Phlegrwan Fields. ; 
The loss of Professor Phillips’s presence at the meetings of the British Associa- 
tion, of which he was one of the founders, is irreparable. His genial face and 
lucid words brought sunshine wherever he appeared, and threw light on every 
topic he handled; to him might well be apphed the words—“ quidquid tetigit 
ornavit.”” While lamenting his loss, let us endeavour to imitate the example of 
his untiring industry, his patient pursuit of the beautiful and noble in Nature, his 
honesty of character, his purity of life*. q 
The Volcanic District of the North-east of Ireland.—I have now to direct your 
attention to the district of County Antrim and its neighbourhood as one claiming 
our special investigation, and presenting a multitude of interesting problems con- 
nected with the volcanic phenomena of the Tertiary period. By the labours of 
Berger, Weaver, Portlock, Griffith, Bryce, Tate, Holden, and other geologists 
many of these problems have received a solution; others remain for further dis- 
cussion. It shall be my endeavour to give you a brief summary of the facts and 
inferences arrived at up to this time, and to present you with a connected history 
of the operations carried on by terrestrial agents in this island, from the com- 
mencement of the volcanic era to its close. 
This era, though short as compared with the sum of geologic time, was in 
reality vastly extended, and comprised within its limits several stages or divisions 
characterized by special physical conditions. Speaking in geological terms, it pro- 
bably included the latter part of the Eocene and the whole of the Miocene periods, 
interrupted by long pauses in the outburst of volcanic products. 
But before entering upon the narrative of events which occupied this space of 
time, let us first endeavour to determine the physical limits of the theatre of these 
operations; for it may well be asked, considering the great extent to which the 
volcanic products have been cleared from off the surface of the country by denu- 
dation, with what degree of precision can we define the original limits of the 
volcanic area ? 
Let us for a moment, when replying to this question, turn to a still more recent 
volcanic district for an illustration. When we ascend the cone of Vesuvius, and 
from that commanding station sweep with our eyes the surrounding region, we 
find ourselves in the centre of a plain—the Campagna of Naples—formed of the 
products of volcanic eruptions, but limited through three quarters of a circle by 
‘calcareous hills of older date, and along the other portion by the sea. 
I believe that similarly, but on a far more extended scale, we can trace out the 
original limits of the volcanic district of the north-east of Ireland, and that from 
some elevated stations rising from the central plateau of Antrim these limits may 
‘be almost descried by the uprising of ridges of more ancient rocks in several 
directions. Taking our stand on Tardree Hill, or Sleamish, we see to the south- 
ward the granitic and schistose ridge of Slieve Croob, projected against a back- 
ground of the mountains of Mourne, culminating in Slieve Donard. Westward 
the eye rests on the rugged masses of Slieve Gullion and the Silurian hills of 
Newtown Hamilton. Towards the north, after passing the depression of the 
-southern shore of Lough Neagh and the valley of the river Blackwater, the 
enclosing ridge of old rocks, forming from this distance an apparently unbroken 
line, ranges northward into Donegal and the northern shores of Lough Foyle. The 
ocean now intervenes; but acomparison of the physical characters of the Donegal 
“mountains with those of Islay, Jura, Cantyre, and the Western Highlands leaves 
the impression on my mind that the volcanic region of Antrim was limited north- 
wards along the line of a submarine ridge, and that there is little reason for sup- 
posing that the volcanic rocks of Mull were superficially connected with those of 
this country,—on the contrary, the probability seems to be that the old crystalline 
rocks of the Western Highlands were interposed between the two regions. 
Turning to the eastward, the sea overflows an area at one time occupied by 
voleanic products, but now only partially so, and we are unable strictly to define 
* An interesting memoir of the late Professor Phillips will be found in the ‘Geological 
Magazine,’ yol. yii. p. 801 (1870). - - 
