June 27, 1901] 



NATURE 



19 



Ekman from Sweden. Dr. H. H. Gran and Mr. K. V. Hammer 

 acted as secretaries, and Profs. G. O. Sars and Mohn were 

 invited to take part in the deliberations of the Conference. 



The Norwegian Government received the Conference, the 

 I'rime Minister, Mr. Steen, acting as host, and very cordial 

 messages were received from the King. The Municipality of 

 Christiania also showed a lavish hospitality, and everything that 

 could be done to promote the comfort of the delegates had 

 been thought of and provided for. The meeting lasted from 

 Monday, May 6, to Saturday, May ii, and the work — either in 

 the full meetings, in committees, or, by no means least im- 

 portant, in personal conversation — was practically continuous 

 from early morning till past midnight. The result was, on the 

 whole, highly satisfactory ; concessions had doubtless to be 

 made all round, and some conclusions which might not be the 

 best conceivable had to be accepted as the best obtainable ; but 

 the harmony of the international fellow-workers was unbroken, 

 and during the whole meeting no question had ever to be put to 

 the vote, agreement in every case being unanimous. The presi- 

 dent of the Congress was Prof. Nansen, but the chief delegate of 

 each of the chief countries represented presided each on one day. 



The first work was the revision and completion of the 

 Stockholm programme in its two divisions, which were known 

 as the hydrographical and the biological. The former division, 

 having been well elaborated at Stockholm, was easily disposed 

 of, but the biological programme was entirely recast, several 

 independent schemes of vtork which had been brought forward 

 by the delegates having to be combined with the provisional 

 programme. Next came the question of the organisation of the 

 scheme of international research, which was only partially 

 achieved. As it was necessary to refer several points to the 

 various Governments concerned, it was decided that a committee 

 of the vice-presidents should draft a series of recommendations 

 to be sent in the same form to all the participating Governments, 

 but not to be made public until a decision had been arrived at. 

 Finally, a number ol resolutions in the form of " pious opinions " 

 were proposed and adopted. 



The introductory clause of the official report, referring to 

 the complete programme, runs: "Considering that a rational 

 exploitation of the sea should rest as far as possible on scientific 

 inquiry, and considering that international cooperation is the 

 best way of arriving at satisfactory results in this direction, 

 especially if in the execution of the investigations it be kept 

 constantly in view that their primary object is "to promote and 

 improve the fisheries through international agreements, this 

 International Conference resolves to recommend to the States 

 concerned the following scheme of investigations which should 

 be carried out for a period of at least five years." 



A. Hydrographical Work. — The object of this work is defined 

 as the distinction of the different layers of water according to 

 their geographical distribution, depth, temperature, salinity, 

 dissolved gases, plankton (as an index of movement of water) 

 and currents. To effect this object it is recommended that 

 simultaneous observations should be made in the North Sea, 

 English Channel, Baltic and North Atlantic along certain 

 definite lines four times in the year, the middle point of the 

 series of observations being in the first half of February, May, 

 August and November. Instruments and methods are prescribed, 

 and it is provided that meteorological as wellasoceanographical 

 observations shall be made, and that facilities shall be offered to 

 the various national meteorological offices to cooperate in the 

 study of the upper atmosphere at sea by the use of kites. The 

 observations made on each of the international trips are to be 

 plotted on synoptic charts at the earliest possible date after the 

 return of the vessels. Stress is laid on the provisional nature 

 of any determinations of salinity or density made at sea, and on 

 the importance of carrying out such observations with the highest 

 precision in laboratories on shore. The unit of depth is to 

 be the metre, although it is allowable to add the depths in 

 fathoms. The sea-mile is to be the unit of horizontal distance. 

 For temperature, thermometers graduated in either centigrade or 

 Fahrenheit degrees may be used, but all readings are to be 

 reduced to centigrade .'^or publication. While the new tables of 

 the physical constants of sea-water prepared by Dr. Martin 

 Knudsen, of Copenhagen, are to be employed, and are sufticient 

 for their purpose, it is pointed out that it is desirable to have the 

 existing tables of the absorption of atmospheric gases in 

 sea-water revised. The mapping of the deposits on the sea-bed 

 of the area to be studied is another desideratum to which attention 

 is called. It is also pointed out that it is desirable to encourage 



NO. 1652, VOL. 64] 



regular observations of surface temperature and the collection of 

 samples of surface water on board the steamers of regular lines 

 which cross the area under investigation, a branch of v\'ork 

 which has yielded excellent results in the hands of the Danish 

 Meteorological Institute and in those of Mr. II. N. Dickson. 



B. The Biological Programtfie. — Here two classes of recom- 

 mendations are to be distinguished, those referring to obligatory 

 work which each of the nations concerned is held bound to 

 carry out, and to optional work, which, while desirable in order 

 to complete the scheme of investigation, is not of such urgent 

 importance. The areas in which the various nations are to 

 work are suggested both for the hydrographical and the biological 

 researches. Briefly put, they provide that the North Sea south 

 of 58° N. should be divided by the meridian of 2° E., to the 

 west of which British vessels should do the work, to the east of 

 which Belgium, Holland, Germany and Denmark should under- 

 take the sections lying off their own coasts. From 58° to 62^ 

 N., Great Britain, Norway and Denmark would share the work 

 in the North Sea and North Atlantic. From 62° northward 

 would be the sphere of interest of Norway in the .\tlantic and 

 of Russia off the Murman coast. The Baltic and its approaches 

 would be dealt with by the three Scandinavian nations, together 

 with Germany, Russia and Finland. No objection would be 

 made to any of the research vessels extending their operations 

 beyond the area allotted to them provided that the work in that 

 area is not neglected. 



The biology of food fishes is to be investigated in a compre- 

 hensive manner. The preparation of charts is recommended, 

 showing the distribution in all their stages of growth of plaice, 

 sole, turbot, cod, haddock and herring in the North and Arctic 

 Seas, and of flounder, cod, sprat and herring in the Baltic. 

 The observations to yield data for these charts are to be carried 

 out as often as possible and with uniform trawls and other 

 appliances, while the measurement and all particulars of the 

 fish caught are to be recorded in a systematic and uniform 

 manner. 



In this respect optional researches are suggested on the life- 

 history of food fishes with regard to their development, migra- 

 tions and feeding places, all in connection with hydrographical 

 conditions. To help towards this end the liberation of marked 

 fish over wide areas and in large numbers is recommended. It 

 is also considered useful to inquire as to whether fish of difterent 

 species after being caught by various methods are likely to live 

 if immediately liberated. 



The study of the quantitative distribution of pelagic eggs, 

 larvx and young fishes is to be carried out as part of the routine 

 work at all stations where physical observations are made, the 

 method recommended being by vertical hauls of Hensen's large 

 egg-net. As an optional extension of this part of the work the 

 study of the eggs and young of food fishes may be continued 

 in the intervals between the quarterly cruises, and experiments 

 should be made on the artificial fertilisation and hatching of ova. 



The researches of individual specialists are to be promoted 

 by the collection of material as to the local varieties of plaice, 

 herring and mackerel in the entire area subject to international 

 investigation, and such researches may also be extended to in- 

 clude other useful species. The areas where undersized or im- 

 mature fish specially abound are to be very carefully inquired 

 into, and the quantity of such fish landed at the various ports 

 as the result of various methods of fishing are to be ascertained. 

 The statistical methods may be extended by the occasional send- 

 ing out of experts on board fishing vessels to examine the catch 

 as it is brought on board. 



The study of plankton and bottom fauna is to be carried out 

 by qualitative samples being collected as one of the routine 

 operations at the various stations for hydrographic observations 

 on the quarterly cruises, not merely from the surface, but by 

 vertical hauls. Wliere possible, similar collections at other 

 times and at regular shore stations is recommended as an optional 

 extension. Quantitative hauls with Hensen's plankton-net are 

 also recommended, the material collected being ofi'ered for 

 examination to specialists who may be willing to undertake 

 the work of quantitative determination. Endeavours should be 

 made with suitable apparatus to investigate the organisms which 

 inhabit the lowest water layers immediately above the bottom. 

 The macroscopic animal and plant life of the bottom should also 

 be studied, with special reference to the nutrition of food fishes. 

 Among the optional researches which are suggested with refer- 

 ence to the bottom fauna are observations on the bacteria of 

 the bottom and of the water immediately above. 



