Reviews — Geology of Ontario. 91 



from Cornwall to the Isle of Wight is indeed referred to by Mr. Reid, 

 and it appears more reasonable than the idea of transport across 

 country from Devonshire and Cornwall ; moreover, there is no need 

 to invoke a land- connection at that recent period between the Isle of 

 "Wight and the Hampshire coast, if we accept St. Michael's Mount as 

 the island to which tin Avas conveyed by the people of Belerium in 

 "wagons at low tide. 



Dene-holes are briefly dealt with, and the author agrees that they 

 were used as granaries and places of refuge. Other excavations by 

 shaft and tunnel were undoubtedly used simply to extract chalk, but 

 they are not dene-holes. In some cases, however, it seems probable, 

 as at Chislehurst, that excavations by tunnel for chalk were made in 

 a tract previously utilized for dene-holes. 



The author discusses the configuration of the coast of Kent in the 

 time of Caesar, the Groodwin Sands, and Romney Marsh. 



He gives reasons for deciding that Portus Itius, whence Caesar sailed 

 on both of his expeditions to Britain, was Boulogne ; and he claims 

 to have demonstrated " that he did land both in 55 and in 54 B.C. in 

 East Kent — in the former year between AValmer Castle and Deal 

 Castle, in the latter north of Deal Castle." 



One further conclusion may be mentioned with regard to the site 

 of the great Metropolis : — 



' ' The very large number of Palaeolithic implements which have been found in 

 London and its environs prove that in the earliest times it was a centre of population; 

 but it would hardly be safe to infer from the discoveries of bronze and iron tools and 

 weapons and of British coins that the Romans found a town on the site. If there 

 was such a town, it certainly had little political importance ; for while numerous 

 British coins issued from the mints of Verulamium and Camulodunum, not one has 

 been discovered which bears the name of Loudinium. Nevertheless, it may reasonably 

 be affirmed that Loudon existed before the Roman conquest : first, because the same 

 advantages that attracted the traders of Rome would also have commended themselves 

 to those of Britain ; and secondly, I repeat, because it is improbable that a Celtic 

 name would have been given to a town which the Romans had built upon a 

 virgin site." 



II. — Geology of Ontakio. 



IN a paper on the " Grenville-Hastiugs Unconformity" (16th Report 

 of Bureau of Mines, Ontario, 1907), Messrs. Willet 0. Miller & 

 Cyril W. Knight claim to have proved that the Keewatin of South- 

 Eastern Ontario is the oldest series in the region. "An ancient 

 Keewatin lava has, in places, been subjected to little denudation 

 before the deposition of the Grenville limestone, which fills the cracks 

 and openings in the ropy surface of the lava. TJnconformably above 

 the Grenville limestones and Keewatin lavas or greenstones rest the 

 conglomerates and other sedimentary rocks, including limestones, 

 which the present writers class as Huronian. These conglomerates 

 contain not only ordinary fragments of the Grenville limestones but 

 ' eozoon '-like boulders as well, thus showing that the limestone is 

 much older than the conglomerate." They have further found in the 

 conglomerates pebbles of cherty and ferruginous rocks resembling 

 those of the iron-ranges of Lake Superior, and derived from layers or 



