53* 



NATURE 



[December 26, lyiS 



the author's endeavour is tu correlate mean tempera- 

 ture at certain stations with the distribution ol land 

 and water in the neighbourhood of the stations, firs! 

 a definite region, including the Baltit and mosl 

 oi northern Europe, without much range "I latitude, 

 and next fur the world in general, with special 

 1 ference iu latitude. 



It is clear that very definite results are unlikely, 



having regard to the verj irregular distribution of 

 land and its topographical peculiarities; ancfnol less 

 clear that a great deal oi labour must have been 

 involved in obtaining an) result whatever. The tem- 

 perature of a place is affected by the size, distance, 

 and direction of land and water masses in relation 

 to the prevailing winds, and also l>> the reliel of the 



land and the temperature of the neighbouring sea. 



The correction for height above sea-level is apparent!) 

 straightforward and simple, but in regard to the others 

 it was onl) convenient to take as a first approximation 

 the percentage of land included in circles of 5°, io°, 

 and 20 radius, centred at the station in question, and 

 the resulting correlations are by no means easv of 

 interpretation. 



Certain station-, introduce special difficulties, e.g. 

 Haparanda, where the continentality is not the same 

 throughout the year owing to the freezing of the sea 

 in winter. There are, however, some general con- 

 clusions worth quoting: — (1) In winter the effect of 

 land to the west is to lower temperature. (2) In 

 winter the effect of land to the east is almost 

 negligible, so that even in continental areas the lowest 

 temperatures are found near the eastern coasts. 

 (3) The general effect of land in the summer either 

 east or west is to raise temperature, but not to any- 

 thing like the same extent as the opposite effect in 

 winter. 



Special interest attaches to the extension of the 

 investigation with regard to long intervals of time. 

 In the Litorina (early Neolithic) period the climate of 

 the Baltic regions was rather different, as also were 

 the distribution of land and the freedom of access from 

 the Atlantic. In the first paper, which deals specially 

 with this region, the author claims that the alterations 

 of continentality suffice to account for all the historic 

 variations of local temperature. A more important 

 generalisation follows in the second paper, in which 

 the author considers the period immediately preceding 

 the last or Quaternary glacial period. An outline is 

 given of the distribution of land at that period, and 

 an explanation of the formation of ice-sheets bv 

 reason of fall of temperature and increase of snowfall, 

 the argument being almost entirely meteorological. 

 The next step, however, is of a different kind, and 

 the theory of isostasy is summoned to account for 

 the gradual upsetting of an apparently permanent 

 glaciation. The weight of the masses of ice causes 

 the subsidence by slow degrees of the ground below 

 equilibrium being gradually restored bv the fluid 

 interior. The sinking of the ice-surface causes an 

 increase of temperature with consequent melting. 

 The isostatic action is, however, so slow that the 

 surface continues to sink, causing a higher tempera- 

 ture in higher latitudes (inter-glacial period). After a 

 time the equilibrium, which is clearly disturbed in the 

 opposite direction, induces im, static action again, 

 raising the land-surface and causing another glacia- 

 tion. The author considers that this "ebb and flow" 

 has taken place four times in succession, the ampli- 

 tude diminishing each time, as is to be expected. 

 _ The course of these age-long changes is not quite so 

 simple as its general outline, for many irregularities 

 are necessarily introduced by the disposal of the 

 melting ire, which will depend on the geographical 

 features th»is uncovered, and, again, by the locking up 

 NO. 2565, VOL. T02"] 



ol so much moisture into glai iersj but the 1 splanation 

 of such well-known phenomena .1- the warm period of 

 the tertiary >'> this geographical method appears more 

 straightforward than any depending on assumptions 

 as to the effect of charVges in the obliquity of the 

 ecliptic— an effect which we are almost powerless to 

 Forecast . 



The purely meteorological part of the subject is not 

 without difficulties of its own, some vei 

 figures for sea temperature in high latitudes n suiting 

 from the attempt to deal with the earth as a 

 and to allow for the vagaries of land distribution and 

 of ocean currents. The effect of insolation in different 

 latitudes and on different land and water sui 

 a very difficult problem, and so also is the question 

 of precipitation, but Mr. Brooks is not afraid to 

 tackle these difficulties, and must have brought an 

 enormous amount of research to bear, in addition to 

 the very laborious and complicated analysis of the 

 data obtained. It is to be hoped that this subject 

 will not escape the notice of the British Association 

 Geophysical Committee. \Y. \\'. B. 



REPORT OF THE DEVELOPMENT 

 COMMISSIONERS. 



THE report of the Development Commissioners for 

 1 the year ended March 31, 191S, has been pub- 

 lished as a Parliamentary Paper (nS, price i,J. net), 

 extracts from which are 'subjoined. Except so far as 

 the special circumstances of the war have called for 

 extended expenditure or new schemes in respect of 

 food supply and natural products, or for the pre- 

 liminary outlay in the preparation of schemes which 

 may employ labour after the war, the Commissioners 

 have continued the policy which they have adopted 

 since the commencement of the war of confining their 

 advances in the main to ensure the continuity of 

 schemes which were already in working in 1914, 

 and cannot properly be discontinued. In one 

 instance, that of flax-growing, the expansion owing 

 to war needs has led to an increase of the under- 

 taking to a scale on which it is no longer of an experi- 

 mental or educational nature, such as is appropriate 

 for assistance from the Development Fund, and the 

 undertaking has accordingly been taken over bv the 

 Board of Agriculture. 



In the introduction to last year's report mention 

 was made of an advance of 50,000!. for improving the 

 fish food supply by installing motors in fishing-boats. 

 But the problems of this supply are not solved by the 

 mere catching of fish ; there remain the problems of 

 its rapid delivery or preservation. In connection with 

 these latter points the Commissioners have recom- 

 mended an advance of 6750L in aid of landing and 

 entraining facilities at Valentia, and in January, iqiS, 

 they promised to recommend an advance (later 

 fixed at 10,000!.) for the establishment of an experi- 

 mental fish-canning factorv on scientific lines. 



Reference was also made last year to the extra ex- 

 penditure on a largely increased supply of plants for 

 afforestation, and this has continued in the year now 

 under review. Thus an advance of 6005!. to the Com- 

 missioners of Woods for this purpose has been recom- 

 mended ; while in Scotland, in addition to ordinary 

 expenditure, grants of 2000!. for each of the financial 

 years, 1917-18 and 1918-19, were recommended to 

 meet expenditure on the establishment of forest nur- 

 series, and 930L for an additional Forest Officer on 

 the staff of the Board of Agriculture. A sum of 

 1000!. was also made available for preliminary ar- 

 rangements for the afforestation of privately owned 

 lands and a flying survey. 



