echographs from these crossings gave evidence of reflecting layers 

 indicated by diffuse " false bottoms " in moderate depths, between 50 

 and 150 fathoms generally, which had a tendency of moving upwards 

 towards the night. In some cases they apparently consisted of shoals 

 of fish, in others, possibly, squids or else densely packed planktonic 

 organisms. For lack of proper gear no samples could be taken. The}' 

 appear to be associated with the strips of divergence — i.e., upwelling 

 water, rich in nutrient salts, which border the counter-equatorial current. 

 The bottom samples taken by means of the corers, up to 16 metres in 

 length, gave evidence in the same region of multiple stratification, 

 noticed already from the " Challenger " cruise. Probably the equatorial 

 current system has become displaced in latitude by changes in atmospheric 

 circulation, accompanying the variations from glacial to interglacial 

 epochs. 



An interesting but rather unfortunate fact was the highly irregular 

 bottom profiles met with hwe as well as in the Atlantic and the Indian 

 Oceans, where a perfectly flat bottom is rather the exception than the 

 rule. Moreover, where a perfectly level bottom occurs, it sometimes 

 consists of an extensive lava-bed, covered by a thin veneer of sediment. 

 Both circumstances repeatedly led to loss of instruments. The echo- 

 sounding of the sediment thickness gave considerably smaller distances 

 between the sediment surface and the reflecting layers beneath the 

 sediment (presumably basaltic bedrock) both in the Pacific and the 

 Indian oceans (maximum 300 metres) than the far higher values found 

 in the Atlantic (up to 2,500 metres). 



A total of sixty cores was raised from great depths (maximum 

 7,800 metres in the south part of the Mindanao Deep) with a maximum 

 length of an individual core of 16 metres. Once completely investigated 

 by mechanical, chemical, mineralogical, spectroscopic, radioactive, and 

 biological analyses, these extracts from the " records of the deep " may 

 be expected to yield interesting information on the past history of the 

 central Pacific Ocean along our course, extending back in the Tertiary 

 Age. 



By means of a special water-bottle of large capacity (25 litres), 

 samples of sea-water from different depths were collected for radium 

 analysis (by precipitation with barium-sulphate) and for fluorescence 

 analysis on uranium. The disturbed balance between uranium and 

 radium in sea- water due to the precipitation of ionium (5) to the ocean 

 bottom together with ferric hj^droxides is probably the main cause 

 of the surprisingly high radium content of many deep-sea deposits, 

 especially of the Red Clay. Incidentally, the ionium affords a clue to 

 the dating of the different strata from radium measurements. Measure- 

 ments of submarine light in different spectral regions were carried out, 

 partly by means of rectifying cells, down to 200 metres, partly by means 

 of a submarine camera, down to 500 metres (Drs. N. G. Jerlow and 

 F. Koczy). Near the surface measurements were also carried out on the 

 ultraviolet component of submarine daylight. The frequency of 

 suspended particles in different depths was measured bj^ the Tyndall 

 method. 



The study of the large material collected during the cruise, with 

 a total core-length from all the three oceans of 1,640 metres, will occupy 

 several specialists in Sweden and also in other countries for at least 



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