4i8 



NATURE 



[Sei'Temler 3, 1903 



a little more -in formation, for instance, as to the con- 

 stitution of the International Council and its adminis- 

 trative bureau, the address of the ofHice and a brief 

 statement of the objects for which the organisation has 

 been brought into existence. The salient features of 

 the maps of the physical conditions of the surface water 

 might also be expressed in words, and the stations at 

 which -observations were made ought to be indicated 

 on the map of each cruise by dots. We are inclined 

 to lav stress on this point, as without some indication 

 of the kind the maps are difficult to interpret, and the 

 scale is not large enough to permit the figures of each 

 observation to appear. 



The Aug'ust and November cruises were carried out 

 in the Baltic by Finland, Sweden, Denmark, and 

 Germany, in the 'North Sea by Germany and Scotland, 

 and in the North Atlantic and Arctic Sea by Norway 

 and Russia. To these there were added in February 

 observations in the North Sea by Holland, and in the 

 English Channel by England, England and Scotland 

 being separately represented, mainly on account of 

 the different nature of the fishery problems in their 

 respective areas. It may be noted that these bulletins 

 do not touch on the fishery observations, nor on the 

 biological work, (the determination of plankton ex- 

 cepted), which occupy the Vk'hole time of the various 

 national staffs between the quarterly cruises. They do 

 not refer either to the work of the Central Laboratory 

 at Christiania. 



The importance of the bulletin lies in the fact that 

 it gives particulars of the temperature and salinity at 

 a great number of points from latitude 45° to 75° N., 

 observed nearly simultaneously and with comparable 

 instruments of the highest precision, the temperature 

 being determined by means of the Pettersson-Nansen 

 insulating water-bottle and thermometers graduated to 

 the fifth or even the tenth of a degree centigrade, the 

 salinity by estimation of chlorine. 



Both for August and November the central part of 

 the North Sea appears to have been left without obser- 

 vations, but this gap was partly filled up in February 

 when the system of quarterly cruises was more com- 

 plete, and a number of supplementary observations by 

 trading steamers had been added. The indications in 

 the published maps are of a slight freshening along 

 the British coast, a belt of maximum salinity running 

 parallel to the coast towards the middle of the North 

 Sea, increasing in salinity rapidly to the north-west 

 between Scotland and Faeroe, and to the south-west 

 towards the English Channel. The whole of the 

 eastern half of the North Sea shows a rapid freshen- 

 ing towards a stream issuing from the Baltic close 

 along the west coast of Jutland. 



Where the temperature observations were sufficiently 

 close and regular to permit of isotherms being drawn, 

 they present a remarkable relation to the isohalines. 

 In August the one isotherm shown is that of 12° C, 

 which runs from Aberdeen to Lindesnaes, cutting the 

 isohalines at right angles. In the November map, 

 however, the isohalines and isotherms exhibit a most 

 striking parallelism, so that the circulation of the water 

 in that month could be studied with equal facility by 

 considering either the temperature or the salinity. Ihus 

 at the southern end of the North Sea the isotherm of 

 ^3°-5 C. coincides with the isohaline of 35.25 per mille, 

 and the isotherm of 13" C. with the isohaline of 35.00 

 per mille. At the mouth of the Baltic the two sets of 

 lines though parallel do not correspond symmetrically, 

 while on the north-west side of the Baltic stream 10° 

 lies close to 34"/-., on the east side it lies close to 32%., 

 Still the axis of the Baltic stream is the same whether 

 it is drawn from the one set of lines or the other. 



The February map shows the isotherms parallel 

 with the isohalines in the south and east of the. North 

 NO. 1766, VOL. 68] 



Sea, but cutting them nearly at right angles in the 

 more open w^aters of the north and west. The differ- 

 ence in the broad action of the Atlantic in the wide 

 part of the sea and the river-like action of the Channel 

 in the southern part is brought out in a most interest- 

 ing manner. 



It is very important to secure a great extension of 

 surface observations, and this, we believe, is now being 

 done by many shipmasters who make regular observ- 

 ations 'on the various trade routes across the North 

 Sea. Even if these fall short of the high accuracy 

 attained by the special scientific vessels, they will prove 

 invaluable in fixing the general run of the isotherms 

 during the quarterly cruises, and of following the 

 changes which take place between them. 



We consider that these bulletins are satisfactory 

 and full of the promise of large results. The too scanty 

 letterpress is printed in parallel columns in German and 

 English; the title only is in French. 



ARCTIC GEOLOGY. 



DR. P. SCHEI'S preliminary sketch of the geo- 

 logical work accomplished during Captain 

 Sverdrup's four years' exploration of the region west 

 of Smith Sound, an account of which is given in the 

 Geographical Journal for July, makes important 

 additions to our knowledge of Arctic geology. 



About a quarter of a century ago Sir G. Nares's 

 expedition examined the northern and eastern coasts 

 of Grinnell Land down to the north-east corner of 

 Ellesmere Island. The collections brought back by 

 the Fram continue the geological information from 

 this district round the southern part of that land mass, 

 now named King Oscar Land, and all up its w-estern 

 shore to the north of Greely Fjord, including also the 

 eastern coast of a newly-discovered island called 

 Heiberg Land, and the coast of North Devon, south 

 of Jones Sound, thus filling in the angle bet,ween Smith 

 Sound and the group of the Parry Islands. Possibly 

 they complete our general knowledge of this region, 

 for Captain Sverdrup is disposed to think no more 

 land exists to the north and north-west of Heiberg 

 Land. 



Previous explorations, summarised by Messrs. 

 Feilden, De Ranee and Etheridge in the Quarterly 

 Journal of the Geological Society for 1878, proved the 

 existence of crystalline Archaean rocks in the north-east 

 of Ellesmere Island, of ancient sedimentaries, possibly 

 Huronian, along the w^estern coast of Kennedy 

 Channel as far as the north-east angle of Grinnell 

 Land, where they were succeeded by Carboniferous 

 strata (with a little Devonian). West of these were 

 Archaean schists, and those in the south were parted 

 from the Huronians by a tract of Upper and Lower 

 Silurian. Tertiary deposits, presumably of Miocene 

 age, were discovered at more than one spot on both 

 sides of Smith Sound and the channel north of it, and 

 ample proofs obtained of a comparatively recent 

 general elevation of the land, in some cases amounting 

 to a thousand feet. Dr. Schei confirms the .existence 

 of the older Palaeozoics near the middle of Ellesmere 

 Island. Archeeans follow them to the south, and con- 

 tinue along the coasts of Smith and Jones Sounds, 

 appearing also on that of North Devon. On both 

 sides they are succeeded by Cambro-Silurian deposits, 

 and these, just at the western end of Jones Sound, by 

 Devonian, which occur on both sides of the strait and 

 extend some distance up the west coast of King Oscar 

 Land. That formation had been already identified 

 in the Parry Islands, and is now proved to extend over 

 a considerable area. The strait parting Ellesmere 

 Land from Heiberg Land is bordered bv Mesozoic 

 strata, which had already been detected in the Parry 

 Islands, and these in the most northern part of 



