4l»S 



THE VOYAGE OF H.M.S. CHALLENGER. 



Both Ross and Cook were running along the 60th parallel considerably after the date 

 mentioned, but they both speak of the danger of doing so during the dark nights. 

 Unless favoured by the moon or clear weather, no vessel should attempt to proceed on 

 her voyage between 8 p.m. and 4 a.m. whilst among icebergs ; that is, south of about 

 lat. 58° S. ~ • 



At 8 p.m. sail was shortened and the ship hove to for the night. The weather during 

 the day was cloudy and gloomy, but the sun shone out for a few minutes now and then, 

 so that the position could be ascertained by astronomical observation. The wind 

 was moderate and the sea smooth, the barometer rising steadily from 28"537 to 29"023 

 inches; the mean temperature of the air 28°'6, of the surface water 31°*9. Numerous 

 icebergs were in sight all day. 



On the 26th, at 3 a.m. (daylight), sail was made, and the vessel stood to the north- 

 ward. At 9 a.m., the weather being fine with a high barometer for these regions, showing 

 that in all probability this fair weather would not continue, advantage was taken of it and 

 a sounding and trawling were obtained, the depth being 1975 fathoms, Diatom ooze, 

 Station 156 (see Sheet 23). At noon the position of the ship was lat. 62° 26' S., 

 long. 95° 44' E., and there were thirty icebergs in sight, but no pack ice. 



The same difficulty was experienced in obtaining serial temperatures as before, 

 although the thermometers were cooled by a mixture of ice and salt before immer- 

 sion. The surface temperature was 33°, the temperature at 100 fathoms 31°'9, at 

 150 fathoms 34°, and below the depth of 150 fathoms the thermometer came up 

 showing on the maximum side 34° and on the minimum 31°"9, hence it is impossible 

 to say what the precise temperature of the sea was below 150 fathoms ; all that can be 

 asserted is that it ranges between 34° and 31°"9. It is true the bottom thermometer 

 showed 34° on the maximum side and 31 0, 3 on the minimum, but as it was cooled before 



