88 8GIENOE IN SHORT CHAPTERS. 



last visit a boat-house and boat were swept away; and one 

 of the most recent among the tracks that I saw reached 

 within twenty yards of some farm-buildings. 



What has become of the millions of trees that are thus 

 falling, and have fallen, into the Norwegian fjords during 

 the whole of the present* geological era ? In considering 

 this question we must remem'ber that the mountain slopes 

 forming the banks of these fjords continue downwards 

 under the waters of the fjords which reach to depths that 

 in some parts are to be counted in thousands of feet. 



It is evident that the loose stony and earthy matter that 

 accompanies the trees will speedily sink to the bottom and 

 rest at the foot of the slope somewhat like an ordinary sub- 

 aerial talus, but not so the trees. The impetus of their 

 fall must launch them afloat and impel them towards the 

 middle of the estuary, where they will be spread about and 

 continue floating, until by saturation they become dense 

 enough to sink. They will thus be pretty evenly distrib- 

 uted over the bottom. At the middle part of the estuary 

 they will form an almost purely vegetable deposit, mingled 

 only with the very small portion of mineral matter that is 

 held in suspension in the apparently clear water. This 

 mineral matter must be distributed among the vegetable 

 matter in the form of impalpable particles having a chem- 

 ical composition similar to that of the rocks around. Near 

 the shores a compound deposit must be formed consisting of 

 trees and fragments of leaves, twigs, and other vegetable 

 matter mixed with larger proportions of the mineral debris. 



If we look a little further at what is taking place in the 

 fjords of Norway we shall see how this vegetable deposit 

 will ultimately become succeeded by an overlying mineral 

 deposit which must ultimately constitute a stratified rock. 



All these fjords branch up into inland valleys down which 

 pours a brawling torrent or a river of some magnitude. 

 These are more or less turbid with glacier mud or other 

 detritus, and great deposits of this material have already 

 accumulated in such quantity as to constitute characteristic 

 modern geological formations bearing the specific Norsk 

 name of or en, as Laerdalsoren, Sundalsoren, etc., describ- 

 ing the small delta plains at the mouth of a river where it 



