On the Phcenician Tin Trade in Cornwall, by R. Edmonds. 29 
ing long sand-bank, as above described, and if so it is no 
raised beach. 
If it be objected that the layer at Chyandour was twenty-three 
feet above high-water mark, whilst those in different parts of the 
sand-bank were not perhaps hulf that elevation, and that there- 
fore all the layers could not have proceeded from one and the 
same irruption, it may be replied that this is no valid objection, 
inasmuch as the sea must have made complete and unresisted 
breaches over the low sand-bank into the adjoining marsh, whilst 
the higher cliff at Ohyandour resisted the waves and occasioned 
their higher rise. It was probably the highest wave during the 
irruption that left the layer on Chyandour cliff, and one of the 
lower and subsetjuent waves that left the layers on the sand -bank. 
There is no reason for supposing the sea has made any encroach- 
ment on the land in Mountsbay from the time of Diodorus until 
within the last hundred years. During these last hundred years, how- 
ever, its encroachment has been very considerable, owing entirely to 
the removal of the sand, gravel, and shingle from the beach on 
the east and west of Penzance, for agricultural and otlier purposes. 
It matters not what particular part of the beach may be excavated 
for these purposes, for the sea will very quickly distribute the loss 
equally over the wliole. The general effects of this abstraction 
from the beach I have described in my paper last alluded to ; and 
I will now confine myself to such effects as are apparent on the 
"causeway" leading from St. Michael's Mount to Marazion, to 
which Mr. Pengelly has drawn attention, by quoting from Dr. 
Oliver's Monasticon (p. 28) the following passage : — " Bishop 
Lacy, on August 10th, 1425, considering the great losses of 
vessels and lives during the storms in Mountsbay, encouraged 
the faithful to complete the stone canseiray between Marazion and 
St. Michael's Mount." On this isolated passage, Mr. Pengelly 
remarks " that the ' causeway ' apparently begun was not a mere 
footpath to be used at low water, but was intended as a permanent 
