HYDROGR.SECT.— JULY 1905— APPEND.B ( 40 ) 
mine the average salinity and the average deviation from the same. The question is, 
however, whether so much is gained herewith, that an unchanged continuation 
might be defended. I do not think this is the case. 
It is a well-known fact, that the annual variation of the temperature 
depends mainly on the seasons almost everywhere; with regard to temperature, 
therefore, the following remain to be determined: 1) the average, 2) the ampli- 
tudes and 3) the phase-shifting, and also, if possible, a more exact description of the 
temporary temperature-curve, all these at each place and at each depth. The seasonal 
cruises have contributed but little to the determination of these values, and an 
unmodified continuation will probably not be able to give any contribution of 
importance; observations at shorter intervals will be necessary to that end. 
As regards the salinities and the currents deducible from them it is a fact, 
that the changes are so irregular and occur so rapidly, that the conditions found 
during the seasonal cruises must be considered as quite accidental. They are 
not able, therefore, to give a picture of all the important changes in the salinity 
or currents. For this observations at shorter intervals are also necessary. 
The question then arises, whether observations at relatively smaller intervals 
than the three months of the present system, can be made without increasing 
the expense and without any greater employment of the special research-steamers. 
I think this is possible and urgently recommend that the way in which this 
might be done should be thorougly discussed at the meeting of the Hydrographical 
Section and of the Council. In the Baltic a satisfactory system of observations may 
be arrived at by limiting the number of stations and by augmenting the number of 
expeditions. In the Belt Sea and in the Kattegat it might perhaps be possible to 
replace the seasonal cruises by numerous investigations carried out by the fishery- 
inspection-ships etc.; and in the North Sea and the Skager Rak it will no doubt 
be possible to select a few fixed stations and to have them investigated alternately 
by the different countries interested. And if, moreover, hydrographical investigations 
accompany all the biological and fisheries researches, and if the trading steamers 
can be enlisted in our service to a much greater degree than has hitherto been 
the case, I think a satisfactory system of observation will be acquired. Much will 
be gained, of course, if appropriate instruments for deep-sea-observations are taken 
during these cruises. 
I consider it also of fundamental importance, that all the hydrographical 
observations should be published in the Bulletin in extenso (Appendix D) as soon 
as possible after they are finished. 
