The Scottish Naturalist. 45 



the level of the sea, Mr. Austen * considered that the 

 Rhine would then flow down what has again become the 

 bed of that sea, being joined in its course by the Thames, the 

 Tweed, the Tay, and other lesser, streams, the whole forming a 

 magnificent river that poured its waters into the Northern 

 Ocean beyond the British isles, and that along the banks of this 

 great river lived and died the extinct animals whose bones, as we 

 have already seen, are still brought up from this submerged land. 



No great elevation would be necessary to lay bare the 

 bed of the German Ocean, which is nowhere so deep 

 as Loch Lomond, and still less would suffice to lay 

 dry the English Channel. Mr. J. Geikie f considers that 

 an uprise of little more than three hundred feet would 

 accomplish this purpose, and that about one hundred feet more 

 would unite every little island round our coast with the main- 

 land, and the mainland with the continent. There would still, 

 however, be a pretty broad space of water between this upraised 

 land and Norway towards the mouth of the Baltic. Of this 

 upheaved land by and bye animals and plants began to take pos- 

 session, and large forests and other forms ofvegetation grew and de- 

 cayed for ages, their remains forming the submarine beds of peat, 

 and wasted trunks of trees still lying on the bottom of the sea. 



At the period when Britain was last united to the con- 

 tinent, snow and glaciers continued to hold possession of all 

 the uplands, and the climate was still severe. The summers 

 were perhaps somewhat warmer than at present, and a much 

 greater extent of the country would be exempt from the sea air, 

 and its depressing influence on the growth of timber. This will 

 account for the growth of forests in former times on some of 

 what are now the most exposed parts of our coast, as well as on 

 the outlying islands, that are now quite destitute of trees. But 

 the evidence furnished by the trunks of large trees found in the 

 peat of these islands, shows clearly enough that formerly trees 

 had grown their luxuriantly. The growth of the 'trees, the 

 formation of thick peat beds, the gradual elevation of the bottom 

 of the German Ocean into dry land, and its subsequent sub- 

 mergence, makes a long draft on time. 



It will be observed, if in this brief sketch we have succeeded 

 in intelligibly and correctly explaining the phenomena pre- 

 sented by the submerged forests, peat mosses, and mammalian 



* Quarterly Journal, Geological Society, Vol. 7. t Great Ice Age. 



