76 W. A. E. Ussher — Historical Geology of Cornwall. 



sometimes denotes a quarriable knoll, of which he gives examples. 

 Prom this Mr. Peacock infers that the term Hogus only carries us 

 to the middle ages, and not to the time of Diodorus. 



Mr. Peacock l quotes Diodorus Siculus (about 44 B.C.) as follows : 

 " They who inhabit the promontory Belerium are exceedingly 

 hospitable, and on account of the merchants being their guests are 

 civilized by custom in their mode of life. They procure the tin by 

 ingeniously working the earth producing it, which, being rocky, has 

 earthy veins, in which working a passage and melting (the ore) they 

 extract [the tin]. Forging it into masses like Astragals, they carry it 

 into an Island situate before Britain, called Ictis. For the middle 

 space being dried by the ebb they carry the tin into this (island) in 

 abundance in carts. (But a certain peculiar thing happens con- 

 cerning the neighbouring islands lying in the middle (/nera^v) 

 between Europe and Britain, for at full sea they appear to be 

 islands, but by the reciprocation of the ebb of the sea, and a large 

 space being dried, they appear peninsulas.) Hence the merchants 

 buy [the tin] from the inhabitants and export it into Gaul." 



Taking /xera^v to mean " in the middle," Mr. Peacock considers 

 that the Northern Channel Islands were alluded to in the above 

 passages, being of opinion that the Northern Channel Islands were 

 then only insulated at high-water, and that they are called neigh- 

 bouring islands to distinguish them from the more remote islands in 

 the Bay of Biscay. 



Mr. Pengelly 2 observes that, according to Leland, St. Michael's 

 Mount in 1533 was no larger than at present ; that William of 

 Worcester's estimation of its distance from the mainland differs but 

 little from its present site : that " Bishop Lacy's encouragement to 

 the Faithful in 1425 to complete a causeway between Marazion and 

 the Mount, for the protection of life and shipping, denotes that the 

 exposure was as great as in our day ; and as the Confessor's Charter 

 in 1044 describes the Mount as ' juxta mare,' 3 next or by the sea, it 

 may be safely concluded that the insulation of the Mount had taken 

 place more than eight centuries ago." 



After a passing allusion to other competitors for the Ictis of 

 Diodorus, he says, "It is perhaps worthy of remark, that those who 

 have studied the Geology of Cornwall, espoused the cause of the 

 Mount ; while those who fail to do so, appear to have come to the 

 question with their minds imbued with a belief in William of 

 Worcester's statement, that there were 140 parish churches sub- 

 merged between the Mount and Scilly, and accordingly hold that 

 the submergence took place not only since the time of Diodorus, but 

 since the introduction of the parochial system into Cornwall." 



Mr. Pengelly quotes Sir George Cornewall Lewis (An Historical 

 Survey of the Astronomy of the Ancients) as follows : " TimaBus 

 mentions an island of Mictis within six days' sail of Britain which 

 produced tin, and to which the natives of Britain sailed in coracles." 

 He regarded Mictis and Ictis as variations of Vectis. 



1 Peacock, p. 86. 2 Journ. Eoy. Inst. Corn, for 1873, p. 181. 



3 " Sanctum Michaelum qui est juxta mare." 



