298 



Alf Trolle. 



The davit could bear a weight of 500 kg., the same as the wire. 

 Under the quiet conditions in the pack-ice, wliere no sea comes, we 

 could easily manage with such relatively small dimensions of both 

 wire and davit. (Fig. 3). 



If our investigations down to depths of apout 3000 m. had 

 been carried out in open sea, we should have required heavier ap- 

 paratus. 



A series of observations was carried out in the following manner. 



First a sounding was taken with the lead (an ordinary 25 kg. 

 lead). The time taken for each LOOm. to run mil was noted. A man 



I-'ig. о Winch for soundings and hydrographical work; С В. Thestrup phot. 

 a— е. see above (Fia. 2). Ii, meter-wheel, i. davit, k, watiT-bottle. 



held a wooden peg down over the wire, and another stood ready to 

 brake, as soon as the first felt that the lead had touched bottom. • 



It is difficult to feel bottom, when more than ca. 1000 m. of wire 

 was out, as 1000m. of wire weighed 95 kg., thus almost four times 

 as much as the lead (25 kg.). 



Under the calm conditions, which prevailed in among the ice- 

 fields, it was nevertheless possible to note bottom even at a depth 

 of 2400 m. — Further, it was observed when the lead struck bottom by 

 the time for 100 m. of the line running out suddenly becoming greater. 



After the sounding samples of water were taken from various 

 depths. The temperature was read by means of a lens. The lower 

 tap was carefully dried and the water drawn off from the water- 



