I50 



NATURE 



[April i, 1920 



Hydrographical Studies.^ 



HYDROGRAPHY is a backward science, and the 

 very ocean, scientifically speaking, is a neg- 

 lected field. Mr. J. Y. Buchanan, an oceanographer 

 himself, tells us so in his new book of " Accounts 

 Rendered": — "It seems almost incredible that the 

 men of all nations, burning with scientific and ex- 

 ploring zeal, should have entirely overlooked, and 

 apparently despised, this large portion of the world." 

 Our Challenger Expedition had two faults : it cost a 

 great deal of money, and it was done too well. It 

 has led two generations of Englishmen to believe 

 that the thing was done and need not be repeated, 

 and must on no account be asked for again. Yet, in 

 spite of this great old expedition of ours, and the 

 various scientific exploring voyages of the Travailleur, 

 the Gauss, the Siboga, the Albatross, the Thor, and 

 all the rest which have followed it (in other hands 

 than ours), we know perfectly well that our know- 

 ledge of the ocean, both physical and biological, is 

 in its merest infancy. Its fauna we know as we 

 knew that of the shore fifty years ago, a handful 

 here, a handful there, of its physical and physico- 

 chemical phenomena we know a great deal less. 



Nor is this true only of the wide oceans. Twenty 

 years ago we knew, to all intents and purposes, 

 absolutely nothing of the hydrography of the North 

 Sea itself with the one exception of its tides. Its 

 temperatures and densities had never been mapped, 

 their seasonal fluctuations (save at a few shore- 

 stations) were unknown. Even in regard to the 

 tides, and in spite of the great men who have 

 devoted themselves to this favourite subject, we 

 know that we have still a vast deal to learn 

 in theorv, and that in practice our tide-tables 

 fall short of the accuracv which modern conditions 

 demand. Things are beginning to mend. The Uni- 

 versitv of Liverpool has established, not only a chair 

 of oceaftographv, but also a special institute for the 

 studv of the tides; and, under the stimulus of inter- 

 national co-operation, a certain aspect of hydrography 

 has come to be an intrinsic part of the scientific work 

 of our fishery departments. 



All this is to the good, though not yet _ nearly 

 enoue-h. The fishery departments are working on 

 imperfect material, with inadequate staff's and still 

 more inadequate laboratories; but better davs 

 are coming. Even in these hard times the 

 work will go on, and under much better 

 conditions than before, but we shall scarcelv h- 

 satisfied ! For the physical study of the sea is a 

 very great thing indeed. Of its problems many are 

 scarcely formulated, many others doubtless are still 

 unforeseen. There is no end to them; they range, let 

 us say, from the study of the tides to that of 

 hvdroxyl-ion concentrations, from the movements of 

 the great ocean currents to the coefficients of absorp- 

 tion of the sun's rays in the surface-waters of the 

 sea — nay more, they may involve the most funda- 

 mental questions of chemical physiology, in relation 

 to the life and the nutrition of one grade of organisms 

 after another. They call, or ought to call, for the 

 widest physical and chemical knowledge and high 

 mathematical skill. Not only must the oflficials of a 

 department do their daily task, but still wiser and 

 more learned heads must play their part. 



There is not one of these problems which has not 

 its practical side — its influence, direct or indirect, on 

 the lives of fish and the lives of men. But the prac- 



1 Roard -^f Aen-ultnrea'^d Fitheriei : FU't'v TnvestleaM'otn. St. ITI. 

 Hydr-eraphy. Vo'. i., "The Fn^lish Channel," Part v. ; Vol. ii.. " Light- 

 ship Observations." Part i. ; Vol. mi., "The At'ant'c Oc-an." Part i. Rv 

 Dr. Edwin C. Jee Hydrographer on the Staff of the Board. (H.M. 

 Stationery Office. 1910.) 



tical outcome of our knowledge lies, for the most 

 part, a good long way off. The tanner, the dyer, or 

 the brewer, the maker of soap or of glass, even the 

 farmer and the gold-digger, come straight to the 

 chemist with their troubles, for they have learned at 

 last that it is worth their while; yet even now when 

 they do so, as often as not the questions they put 

 only suggest a new line of investigation, instead of 

 finding an answer to hand. And chemistry is all but 

 the oldest of the sciences, while hydrography is a 

 thing of yesterday — or rather of to-morrow. 



But I have left myself no room, after all, to discuss 

 as they deserve those of Dr. Jee's papers published 

 by the Department of Agriculture and Fisheries. 

 They form a diligent and meritorious contribution to 

 the necessary statistics of hydrography. They set 

 forth fully and clearly (i) the variations of tempera- 

 ture and of salinity during a considerable number of 

 years at the Seven Stones Lighthouse, a station of 

 very obvious importance in the neighbourhood of the 

 Scillv Isles; (2) the same phenomena on a cross- 

 section of the English Channel, from the Isle of 

 Wiffht to St. Malo ; and (3) the same again for the 

 surface-waters of the North Atlantic, in a particular 

 area where warm currents appear to branch ofT for 

 the ultimate supoly of the southern and the northern 

 portions of the North Sea. The data, which are very 

 numerous, are furnished by captains of ships and 

 the keepers of the lighthouse ; and Dr. Jee's business 

 has been to reduce to order, to analyse, and. above all, 

 to discuss this large mass of observations. The pheno- 

 mena so elucidated, and the deductions drawn from 

 them, are too numerous to be discussed here. 



On one curious point, and one only, we may say 

 a word. Dr. Jee pays a good deal of attention to a 

 favourite theory of certain meteorologists (Dr. Otto 

 Pettersson among them) that there is a marked 

 alternation of temperatures between the "odd" and 

 the "even" years; that there is at least a tendency 

 for the years of even number to be warmer than the 

 odd. Dr. Jee finds considerable support for this 

 theorv in the surface-waters of the sea, but subiect 

 to curious limitations. He tells us that " it is a fact 

 of undoubted significance that, for a very wide stretch 

 of the Atlantic extending from the coast of Cornwall 

 at least as far as -^5° W., the November means are 

 in the aggregate of substantially higher value in the 

 years of even number, and that this value culminates 

 in the area of maximal temperature. . . . This 

 periodicity is a general feature of the waters of the 

 Atlantic east of -^5° W., and the persistence of its 

 occurrence is amply demonstrated by the zonal means, 

 which regularly alternate high in the November of 

 an even year and low in the year following." 



There is here, in short, some definite evidence ad- 

 duced bearing on the important question of a regular 

 two-year "pulse" of the Gulf Stream. But during 

 other parts of the vear exceptions become perplexingly 

 numerous, and Dr. Jee himself tells us that 

 "examination of the monthly means . . . shows that 

 only in November do they exhibit anv appreciable con- 

 formability to the odd and even rule." Even if the 

 phenomenon were -only clearly manifested in Novem- 

 ber (in this particular region), it might still be of 

 great importance, and we should like to know a 

 great deal more about it. The fact that we are left 

 without a firm hold of the thing is not Dr. Jee's fault 

 at all, but depends on the fact that he is. still only 

 able to deal in detail with a particular and limited 

 area. A similarly detailed account of the surround- 

 ing areas would soon, I imagine, convince us whether 

 we were dealing with a real phenomenon or not, 

 and if it confirmed would begin to heln to explain it. 

 D'Arcy W. Thompson. 



NO. 2631, VOL. 105] 



