Introduction. 



ù 



/aptain Gunnar Isachsen had planned to make oceanographical in- 

 vestigations during his expedition with H. M. S. "Farm" to Spitsbergen 

 in 1909. Unfortunately they had to be given up, as the thermometers 

 ordered from Richter did not arrive until the expedition had left Tromsø 

 and was beyond means of communication. During the second expedition, 

 in igiOj a great many vertical series of deep-sea observations were taken 

 in the waters west of Spitsbergen; and observations of the sea-surface 

 were taken during the whole cruise. The results of these investigations 

 are given in this paper. 



Fig. I shows the positions of the stations and the dates when these 

 stations were taken. The lines connecting the stations indicate the sections 

 drawn in Pis. IV to VI. It will be seen that the stations were often quite 

 near each other, thus rendering the material ver}^ valuable for a close stud}' 

 of man}' details. Most of the observations have been made by Commanders 

 A. Hermansen and J. C. Petersen-Hansen, of the Royal Norwegian Navy. 

 They have taken a very keen interest in the investigations, and have 

 worked almost incessantly as often as they got the opportunity of making 

 oceanographical observations. 



The expedition had three water-bottles, vis. an Ekman Reversing 

 Water-Bottle, a Pettersson Insulated Water-Bottle of the old model, and a 

 Pettersson-Nansen Water-Bottle (the smaller size). The reversing water- 

 bottle was used in the deep strata from 600 metres downwards, and often 

 also at 400 and 500 metres. It did not always close properly, so that some 

 of the watersamples are of no value on account of admixture with water 

 from the upper layers. These cases will be especially noticed in the tables, 

 where a column contains indications of the instrument used. The insulating 

 water-bottles were used everywhere in the upper strata, except at the 

 surface, where the samples were taken with an ordinary bucket, and at 

 a few stations, where Ekman's apparatus was partly employed. 



Vid.-Selsk. Skrifter. I. M.-X. Kl. 1912. No. 12. 1 



