had been experienced in the " Albatross " expedition, and on this 

 occasion the wire weighed as much as 18 tons. Checking the depth of 

 the net was discussed, for it was pointed out that the deep sea ma\' not 

 have an even bottom, but may show many irregularities which echo- 

 sounding would be able to detect. 



THE PACIFIC CRUISE OF THE SWEDISH DEEP-SEA 

 EXPEDITION 



By Hans Petterssox, Goteborg 



(Communicated by Anton F. Bruun) 



On 27th August, 1947, the Swedish Deep-sea Expedition on board the 

 four-masted motor schooner' " Albatross " (1,450 ton d.w.) started from 

 Balboa for the Pacific part of its circumnavigating cruise(l). Our 

 equipment, including the long " piston-core " samplers (Dr. B. 

 Kullenberg)(2), the special Bofors depth-charges, exploding at 300-3,500 

 fathoms, with surface hydrophones and oscillograph or wire-recorder for 

 recording deep sediment echoes (Professor W. Weibull)(3) had been 

 tested with good results from the Government research ship " Skagerak '■' 

 during an experimental cruise to the western Mediterranean in 1946(4). 

 During our first Atlantic crossing, Madeira-Martinique, long cores had 

 been successfully raised from great depths, and the thickness of the sedi- 

 ment carpet measured. The ship, prior to the start, had been converted 

 into a floating laboratory with cabins for a science and technical staff of 

 ten to twelve, spacious laboratories for different purposes, workshop, 

 aquarium, special cool-storage for the sediment cores, &c. In the 

 fore hold the large electricallv driven deep-sea winch, capable of hoisting 

 a load of up to 10 tons with a maximum speed of 100 metres per minute, 

 together with a wire drum holding up to 12,000 metres of wire rope, 

 had been installed. In the aft hold the diesel-electric plant energizing 

 the winch with 140 k.w. was placed. Other winches on deck included 

 a " series-winch " for water-sampling and reversing thermometers with 

 @,000 metres of 4 mm. wire rope, a cable winch for subsurface light 

 measurements, &c. A special feature was the recording echograph, 

 especially made by Marine Instruments Co. of London, which, under 

 favourable conditions of wind and swell, drew continuous records of the 

 bottom profile to within 1 or 2 fathoms, down to depths exceeding 4,000 

 fathoms. • 



The very heavy gear used made it advisable to lay the course largely 

 within the equatorial calms, avoiding as far as possible latitudes beyond 

 20° North and South. This, on the other hand, called for air-conditioning 

 of the cabins and laboratories in order to keep the staff efficient in the 

 warm and moist climate met with. The itinerary had also been chosen 

 so as to minimize the risk of being hampered in our work by hurricanes, 

 typhoons, and adverse monsoons. Actually very few working days were 

 lost through bad weather. 



The Pacific cruise included four complete sections across the, counter- 

 equatorial current and its neighbourhood where frequent oceanographic 

 stations down to the bottom and still more frequent temperature measure- 

 ments in the upper layers, made by means of a bathythermograph, were 

 carried out, affording unique material for future dynamic anah^sis. The 



