TRANSACTIONS OF THE SECTIONS. 109 
which points they are distant little more than 27 miles in a straight line; though the 
distance from Penzance Pier (the usual starting-place for vessels from the main land) 
is about 40 miles to St. Mary’s Pool. So far from being mere rugged rocks, these 
islands afford a pleasant home to between 2000 and 3000 inhabitants ; the total popu- 
lation having been computed in 1851 at 2601 souls, the majority of whom dwell upon 
St. Mary’s, though five of the other islands, viz. Tresco, St. Martin’s, St. Agnes, 
Bryher, and Sampson, have a scattered population upon them nearly in proportion to 
their relative size. As the character of the rocks (being almost exclusively granitic) 
is very similar to that of the extreme promontory of Cornwall, it has been suggested 
by some writers that they may have been originally united with the main land; and 
traditions are not wanting of a very ancient date which might serve to confirm this 
opinion, were there not many countervailing reasons to be alleged in opposition. 
From the circumstance that the Gulf or Woolf Rock, which lies midway between 
Scilly and Land’s End, is of greenstone and not of granite, and that in dredging the 
sea-bottom between these two points, shells and sea-weeds have been occasionally 
brought up clinging to greenstone or clay-slute, it is conceived that a tract of metamor- 
phic rocks exists beneath the ocean between the mainland and the Scilly Isles, and 
that they are thus outliers only of the great granitic range of Devonshire and Corn- 
wall. Many circumstances tend to prove that the conformation of the islands is very 
different now from what it has been even within historic times. Local tradition 
asserts that in former days there was a narrow causeway by which persons could 
pass across Crow Sound from St. Mary’s to St. Martin’s, and the ledge of rock which 
is visible at low water a little below the surface in this part is still called “ the 
Pavement.” ‘Then again the Gugh, which in the time of Borlase (about 100 years 
ago) is described as “a part of Agnes and never divided from it but by high and 
boisterous tides,” is now always an island at spring tides, and there is sufficient depth 
of water in the mid-channel for a boat to shoot across, the bar. ‘These considera- 
tions would seem to show that there has been a decided sinking of the land in these 
islands, even during the last century ; and another fact which came to the author’s 
knowledge while sojourning for a few weeks in the isles confirms this opinion. The 
masons who had been engaged in laying the foundations of a large warehouse be- 
longing to Mr, Edwards, a short distance from the Strand, in the Pool of St. 
Mary’s, when they had dug down several feet below the surface, came across the 
remains of former wooden buildings, which at one period must have been on a level 
with, if not above the sea, although at that time considerably below it. Possibly at 
no very remote period, geologically speaking, the whole of this group to the north, 
including Bryher, T'resco, St. Martin’s, and the adjoining islets, have formed one con~ 
tinuous island, as the soundings even now between the contiguous portions are very 
shallow, and several of them can be reached from the others by walking over the 
bars at low water. With reference to the question of continuity at any former period 
with the mainland, Mr. Statham gave some curious particulars of the tradition re- 
specting a tract of country called the ‘“ Lionesse,” formerly alleged to have united 
Scilly with Cornwall, and referred to the junction of the slate with the granite at 
Marazion Bay, and also at a point immediately behind Penzance Pier. He had made 
diligent search throughout several of the islands to try and discover any traces of a 
similar collocation of rocks in Scilly; and although he had not found sufficient to 
warrant him in asserting the fact of a former continuity, he had met with unmis- 
takeable proofs of the existence of clay-slate both on the Garrison Hill and on the 
top of Newford Down; which served to show that the Scillian group was more closely 
allied in the structure of its rocks to the formations on the mainland than had pre- 
viously been supposed. ‘Ihe position in which the traces of slate rock were found 
were in a pit to the right of the path leading from the Star Fort on the Hugh, to the 
two dismantled windmills on the summit of the Down; and similar indications had 
presented themselves in a pit not far from the telegraph station at the summit of 
Newford Down. 
The author next adverted to the different aspect of the islands as visited from the 
SW. or the N., where they are subjected to the wear and tear of the rough Atlantic 
waves, and to their smooth and rounded appearance when approached from the main- 
¥and. To the violence of the ocean, lashed into fury by the wintry gales, he attributed 
the craggy and rugged appearance of the rocks, the existence of caverns, and of pro- 
