1895- ^û. 9. H\'DR.-BIOL. STUDIES OF THE XORW. FISHERIES. 33 



prett\- consistent under all meterological conditions, \iz., about 4*».« 

 Subsequent investigations have, however, shewn that the difference, down 

 in tlie deep, may be much greater than assumed by Boeck, and, especi- 

 ally, one has found that the colder layers beneath (3 % may be of verj' 

 great thickness. The obser\^ations made b}- 0. S. Jensen, and 5^. A. 

 Buch^ give the most numerous examples of the extent to which the 

 temperature of the sea is exposed to changes. As an example I here 

 quote tlie following from 5. A. Buchs report for the year 1886. 



ist March. Between Svartogrunden and Skarsholmen, Holsoerne. 

 (Islands).« 



o Mètres, Temperature 0.3 

 10 — — 0.60 



20 — — 0,6 



30 — — 1,3" 



40 — — 1.5 



60 - - 3-5'' 



80 — — 41*' 



120 — — 4.30 



Furthermore .6tli March, SE. of Saugo Lighthouse. ^^ 



o Mètres, Temperature 1.2 



10 — — 1.2** 



20 — — 2.3 



40 — — 3.20 



80 - — 5-9" 



100 — — 6.0 



130 — — 6.70 



160 — — 6.8« 



whilst fourteen days previously the conditions were mainl\- othenvise. 

 We thus find, 



s 1 5th February. Half way between Utsire and Ferkingstadoerne 

 (Islands}.« 



o Mètres, Temperature 3.9 



20 [ — — 41" 

 30 I 



40 — — 4-2 



60 — — 4-3 <» 



1 See their Report to the Home Department for the year concerned. 

 Vid.-Selsk. Skrifter. M.-X. KL 1S95. No. 9. 



