0. Nordgaard. [No. 8 



according to the season of the year. Depths under 200 metres 

 were fomid to be, as a rule, oiitside the influence of athmospherical 

 conditions, at least the observations of a whole year had proved 

 little variation. 



Professor Mohn, however, had already in 1887 (1, p 88) noticed 

 that the deep basins of the fjords had also shown considerable 

 changes of temperature. As instance was given the Varanger fjord, 

 where the variations of the temperature of the deep layers were 

 most striking, Norwegian investigators had measured 2,6 — 5,7 ^ 

 C. at depths under 200 m.. while a French expedition (Pouchet 

 and Martial on the "Coligny") in 1881 measured 1,5 — P,3 C. at a 

 corresponding depth. Mohn says about this: „I have sought to place 

 the said variations in connexion with the temperature observed during 

 the preceding period at the surface of the Sea, on the coast, and 

 in the atmosphere. In some cases there would seem to be agree- 

 ment. Thus, for example, the low temperature in the Varanger- 

 fjord during the summer of 1881, must obviously be ascribed to 

 the unusually cold winter and spring in Finmark, when the tempere- 

 ture of the air at Vardø, from October 1880 till June 1881 was 

 2,5° to 4,0° below the normal temperature, and when vast masses 

 of ice kept drifting during the spring of the coast of Finmark. 

 But on the other hand, the temperature, in depths of 100 fathoms, 

 at Lødingen 1879 and 1880, and in Altenfjord during 1882 and 

 1883, would appear to have been well nigh uninfluenced by the 

 varying thermal conditions in the atmosphere and at the surface 

 of the sea. The material before me will not suffice to explain the 

 proximate cause of the variations in temperature on the banks and 

 in the depths of the fjords shown by the observations to have 

 occurred there. Meanwhile, the positive results prove the existence 

 of variations apparently unperiodical in character." 



Since Mohn wrote this a great number of observations have 

 been undertaken of the physical conditions of the northern seas. 

 The Scagerack has been thoroughly studied, chiefly by Swedish 

 investigators, and the results published in comprehensive works. 

 Also the coast and fjords of Norway have during later years been 

 subject to systematical investigations. It was to be expected that 

 the latter must throw new light upon the question treated by Mohn 

 of the natural conditions of the deep layers of the fjords, and I 

 shall in the following try to set off some of the characteristical 

 features of the matter in the new light. 



