The expedition then went direct to the Antarctic and landed the shore party on the Barrier.  Neither on this trip nor on the Fram’s subsequent voyage to Buenos Aires were any investigations worth mentioning made, as time was too short; but in June, 1911, Captain Nilsen took the Fram on a cruise in the South Atlantic and made in all sixty valuable stations along two lines between South America and Africa.

An exhaustive working out of the very considerable material collected on these voyages has not yet been possible.  We shall here only attempt to set forth the most conspicuous results shown by a preliminary examination.

Besides the meteorological observations and the collection of plankton —­ in fine silk tow-nets —­ the investigations consisted of taking temperatures and samples of water at different depths The temperatures below the surface were ascertained by the best modern reversing thermometers (Richter’s); these thermometers are capable of giving the temperature to within a few hundredths of a degree at any depth.  Samples of water were taken for the most part with Ekman’s reversing water-sampler; it consists of a brass tube, with a valve at each end.  When it is lowered the valves are open, so that the water passes freely through the tube.  When the apparatus has reached the depth from which a sample is to be taken, a small slipping sinker is sent down along the line.  When the sinker strikes the sampler, it displaces a small pin, which holds the brass tube in the position in which the valves remain open.  The tube then swings over, and this closes the valves, so that the tube is filled with a hermetically enclosed sample of water.  These water samples were put into small bottles, which were afterwards sent to Bergen, where the salinity of each sample was determined.  On the first cruise, in June and July, 1910, the observations on board were carried out by Mr. Adolf Schroer, besides the permanent members of the expedition.  The observations in the South Atlantic in the following year were for the most part carried out by Lieutenant Gjertsen and Kutschin.

The Atlantic Ocean is traversed by a series of main currents, which are of great importance on account of their powerful influence on the physical conditions of the surrounding regions of sea and atmosphere.  By its oceanographical investigations in 1910 and 1911 the Fram expedition has made important contributions to our knowledge of many of these currents.  We shall first speak of the investigations in the North Atlantic in 1910, and afterwards of those in the South Atlantic in 1911.

Investigations in the North Atlantic in June and July, 1910.