-Deptli. 



10th July 



Saliiiitj-. 



Temperature. 



30th 



Salinity. 



September 



Temperature 







metres 



34.22 7oo 



11. 1« 



32.10 7oo 



9.450 



10 



71 



34.22 „ 



10.42" 



32.45 „ 



9.6" 



iiO 



!) 



34..55 „ 



7.75" 



32.69 „ 



9.80 



30 

 40 



•1 



34.87 „ 

 34.94 „ 



6." 

 5.05" 



32.75 „ 

 33.81 „ 



9.50 



60 

 80 



5; 



51 



35.03 „ 

 35.03 „ 



4.520 

 4.60 



33.94 „ 

 33.94 ,. 



10.0 

 10.0 



12U 



200 



5? 



;7 



35.19 „ 

 35.38 „ 



4.90 

 5.3" 



34.53 „ 



7.8" 



In comparing these two tables it will be seen that 



1- The 35 curve wliicli, in July, was 50 m. l^elow the surface 

 must be sought for in September at depths exceeding 120 m., 

 the 34.5 0/^,0 curve was, in July, at a depth of 20 m., but in 

 September was found at a depth of 120 m. 



2- The Surface Salinity decreased from 34.2 to 32.1 0/^^. 



3- The Surface Temperature sank from 11" in July, to 9V2" in 

 September, but, as a set off, the tem])erature down in the 

 deep rose considerably; for instance from 4.6" at a deptli of 

 80 m.. to 10". 



These conditions remind one greatly of those which have 

 een shewn to exist on PI. 5, Figs. 3 and 4, in respect to the west 

 coast. The conditions on the banks in the North are, however, 

 ^^^ ' "^°^'° instructive, because it must be presumed that the trans- 

 P acement of the temperature, downwards, is there not so dependent 

 on currents as on the west coast where the Baltic current plays a 

 gieat part. It was, moreover, very instructive to find that the 

 lesh water played a gi'cater and greater part the further a fjord 

 ^^■as entered. 



It thus shews that in the North, simultaneously with the 

 increased thickness of the fresh layers, a period of heavy rain 

 m. As the accompanying tables shew, the rainfall increases 

 gieatly ni September, and from that month, throughout the entire 

 ^" umn until January or February, a lengthy season of rain occurs. 

 ^ IS an ^ interesting fact that, just at that time, the fresh layers 

 ^f.\r^^^ '" thickness, and that it is in the fjords, where the rain- 

 j'\ ^^^I'o^gli tlie agency of the rivers is most perceptible, that the 

 ajers chiefly increase. One factor, which also must be regarded 

 '^ great weight in respect to these conditions, is the influence 

 0^ the winds. 



^ -I; m accordance with the annual reports of the Meteorological 



^nstitute, one draws curves representing the frequency of the various 



^^"i< s during the various months of the year, it will be seen (as is 



so shewn m Capt. Rung's atlas of the liarometrical pressure over 



- orthern Ocean) that, during summer, westerly winds are the 



^ost prevalent along the whole of the north west coast of Norway. 



^^ ese must, during the summer, contribute to force the Atlantic 



j|-a ers in towards the land. On the other hand, during the aut- 



elT ^'^'^ ^^'"^*^^" **^*^ f^ii"ection of the wind is, to quite a paramount 



e-^^ent, south easterly, interrupted, however, occasionally, by westerly 



^a es. The south easterly winds thus drive the water out of the 



jords to the banks, and the gales must, on the whole, mix up the 



Doclies of water, and that to a great depth. 



That such a mixture must take place to a very great extent 

 is clear, it appears to us, from the salinity becoming steadily less 

 as the autumn advances. The homogeneousness is greatest in 

 January and February, as both the atmosphere and the fresh water 

 from the rivers cool, especially, the upper layers. 



a?/txoXv^ 



QjA^/l 



Fig. ]. Rainfall in millimetres, during' tlie various months of the year, at 



Srolvser and Horo. 



It is known that layers of water of different specific gravities 

 arc not at all inclined to combine. Thus the Baltic current, 

 during the summer, floats upon the Salter layers beneath, without 

 its being possible to observe any admixture. 



These conditions do not, at all events, exist in the North 

 during the autumn, or in western Norway. This is seen, for in- 

 stance, when tlie density of the water during the winter at various 

 depths is calculated. The density of the Ocean water during the 

 various months of the year may be calculated from Figs. 5 and 6. 

 If one takes an example from February, one obtains the 

 following figures : — 



metres 1.02666 



10 „ 2666 



20 „ 2664 



30 „ 2670 



40 „ 2679 



50 „ 2681 



60 „ 2679 



70 ,, 2678 



80 ,, 2670 



90 „ 2681 



100 ,, 2686 



110 „ 2682 



120 „ 2683 



130 ,, 2689 



140 „ . . . : 2689 



150 „ 2688 



160 „ 2688 



170 „ 2689 



180 „ 2691 



190 „ 2696 



200 „ 2697 



210 „ 2700 



220 „ 2705 



230 ,. 2710 



240 „ 2715 



250 „ 1.02720 



