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1757/1822 | Submarine forest of Mounts Bay noted by Rev W Borlase, hazel, and to a smaller extent of alder, elm and oak

So far back as the year 1757 the submarine forest of Mounts Bay was 
noted by the Rev. W. Borlase, and was subsequently described by Dr. Boase 
in the year 1822. The latter represents it as buried beneath deposits 
of sand and gravel, the removal of which by the sea is constantly laying 
it bare the outward prolongation of the vegetable bed extending beneath 
the sea. Between Penzance and Newlyn he notes a bed of vegetable 

1 See W. A. E. Ussher on ' The Recent Geology of Cornwall ' (articles reprinted from the Geol. 
Mag.), 1879 > anc * the Post-Tertiary Geology of Cornwall (printed for private circulation), 1879. 



remains reposing on the sand, the relics of a wood mainly composed of 
hazel, and to a smaller extent of alder, elm and oak ; while hazel-nuts and 
the remains of insects, especially of beetles, are abundantly preserved. 

A small portion of a submarine forest occurs at Millendreth Bay 
near Looe. Another at Maen Forth to the south-west of Falmouth has 
been described by the Rev. Canon Rogers, who observed the stump of an 
oak in its position of growth with peaty material enclosing its roots and 
containing the remains of the common yellow flag (Iris pseudacorus] still 
flourishing in the adjoining swamp. 1 He also noticed the remains of a 
submarine forest with stumps of oaks and willows in their original 
situations a little above the level of low water at Porthleven near 
Helston. Mr. Nicholas Whitley has described another at Porthmellin. In 
the Hayle estuary, the Dunbar Sands at the mouth of the canal at Perran 
Forth, Lower St. Columb Forth, Mawgan Forth, and numerous other 
localities, traces of submarine forests also occur. In 1898 we observed 
a tree stump detached from its original position on Pendower beach in 
Gerrans Bay, indicating a submarine forest in that vicinity. 

The subsidence of the land which these forest beds imply is con- 
firmed by the evidence of the deposits which line the mouths of our 
estuaries. The search for stream-tin has been the means of dissecting 
these accumulations below the level of the sea, both at Restronguet 
Creek and at Pentuan, where remains of a forest growth in its natural 
position are buried beneath an accumulation of deposits exceeding 
50 feet in thickness, which overlies the stream tin. At Pentuan, Mr. 
Colenso, in 1829, found roots of the oak in their natural position at the 
base of this deposit with oyster shells still fastened to some of the stumps. 
These were overlain by a stratum of dark silt, about a foot in thickness, 
on the top of which was spread a layer of like extent formed of the 
leaves of trees, hazel nuts, sticks and moss, the moss in a perfect state of 
preservation, and affording evidence of having grown in the position 
where it was found. This latter layer occurred at a depth of about 30 feet 
below the level of low water, and supported a stratum 10 feet thick 
sprinkled with wood, hazel nuts, together with the bones and horns of 
deer, oxen, etc. ; and shells of the same species as those which now exist in 
the neighbouring sea arranged in layers in such a position as to suggest 
that the animals lived and died where their remains were found. In an 
overlying bed of sand, 20 feet in thickness, were the remains of trees 
lying in all directions, together with the relics of red deer, and the bones 
of whales. This in its turn was overlain by another bed of sand and gravel 
20 feet thick, which extended to the surface. On the upper portion of 
the superficial layer, on the level with the low water at spring tides, were 
found the remains of a row of wooden piles, apparently used in the con- 
struction of a footbridge, which, if correct, would imply a subsidence of 
the land since that portion of the human era when man had reached the 
stage capable of such construction. 

1 In the submerged forest at Maen Forth Mr. Samuel Roberts discovered the horns of a deer at 
present in the possession of Mr. Robert Fox of Falmouth. 



The Victoria history of the county of Cornwall. Edited by William Page"