June 8, 1905] 



NA TURE 



129 



mentary to us as a nation to say that our patriotism, 

 fear of death, or nerves compare unfavourably with 

 similar attributes of the Japanese ; and, after all, this 

 is a matter of opinion. The fact to face is the trans- 

 formation which science has effected in Japan, and 

 the sooner our statesmen are educated to see it, the 

 more promising will be the outlook for the British 

 nation. 



SOLAR CHANGES AND WEATHER. 



DURING the last few years more than usual atten- 

 tion has been paid to the question of the 

 relationship between sun-spots or prominences and 

 " weather," and to the possibility of being able in 

 the near future to forecast the characters of approach- 

 ing seasons. Quite recently in this Journal (vol. Ixxi. 

 p. 493, March 23) we referred briefly to a pamphlet 

 published by the United States Department of Agricul- 

 ture, Weather Bureau, summing up the general state 

 of the problem of long-range weather forecasting. 

 In this it was stated that advances in the period and 

 accuracy of weather forecasts depend upon a more 

 exact study and understanding of atmospheric pres- 

 sure over large areas, and a determination of the 

 influences, probably solar, that are responsible for 

 normal and abnormal distributions of atmospheric 

 pressure over the earth's surface. 



In the April number of the Popular Science Monthly 

 the question of the relationship between sun-spots and 

 weather is summarised in an article by Prof. Ernest 

 W. Brown, of Haverford College. In this we have 

 an interesting account of the problems waiting solu- 

 tion, and he brings together in a very clear manner 

 a general survey of the relationship, or rather non- 

 relationship, as he concludes to be the case. Thus 

 he says, " it is highly probable that the direct effect 

 of the spotted area is unimportant compared with the 

 effects produced in our atmosphere by other causes." 

 In his final summing up he remarks that his opinion 

 is expressed by Prof. Cleveland Abbe, who stated 

 that: — " The key to the weather problem is not to be 

 found in the sun or indeed in any external influence, 

 but that the solution is to be worked out by the 

 conditions which hold in the atmosphere itself — con- 

 ditions which can only be discovered by a thorough 

 examination of the internal laws of motion, quite 

 apart from any external forces which may modify 

 the results." 



In referring to the difficulties which are met with 

 in examining the meteorological conditions on the 

 earth's surface. Prof. Brown points out that observ- 

 ations made " at one place should be kept separate 

 from those at other places, for it is theoretically 

 possible and even probable that a maximum at one 

 place of observation may occur at the same time as a 

 minimum at another place. For example, the yearly 

 averages might show that a maximum rainfall in 

 one place always occurred with a minimum rainfall 

 in another and vice versd." 



In the last quotation Prof. Brown makes a sugges- 

 tive remark which recent work has shown to be an 

 actual meteorological fact ; it has already been com- 

 pletely established for pressure, and must therefore 

 hold good as regards rainfall, since the latter depends 

 on the former. 



In the case of these variations of barometric pres- 

 sure it has been shown, and referred to at some 

 length in this Journal (vol. Ixx. p. 177, June, 1904), 

 that there exists a barometric see-saw on a large 

 scale the presence of which has been amply corro- 

 borated by Prof. Bigelow, of the United States 

 Weather Bureau. There seems little doubt that it is 

 this pressure change that will eventually prove the 

 " key " to the situation, and its solar origin has 



NO. 1858, VOL, 72] 



already been suggested in the changes in the frequency 

 of prominences, which are, after all, allied to sun-spots. 

 Up to the present time those who have been at- 

 tempting to explain variations of weather on the 

 supposition of solar changes have been looking for 

 the effect of solar action as either increasing or 

 decreasing simultaneously the rainfall over the whole 

 earth. The consequence has been that a study 

 of a great number of statistics has shown that in 

 some regions the rainfall varies directly with the 

 number of sun-spots, and that in others the variation 

 is inverse, while, again, in other parts there seems to 

 be no apparent relation at all. In fact, these deduc- 

 tions, though quite correct, have led to the conclusion 

 that the solar connection is of a very questionable 

 character, as it was considered impossible for such 

 opposite results as the first two just named to have 

 their origin in one solar change. 



It is "the employment of this incorrect workmg 

 hypothesis that has probably retarded the progress of 

 the study of the connection between solar and meteor- 

 ological changes. , , . . 



The now recognised existence of this barometric 

 see-saw shows that the sun's action must have a 

 double effect on our atmosphere, and this of an 

 opposite nature. Such a result is quite natural, and 

 it is curious that use has not been made of it before. 



When it be considered that the amount of air in our 

 atmo-iphere is a constant quantity, a greater piling up 

 of it on one side of the earth must necessarily mean 

 a diminution in the antipodal regions. If greater 

 heating power of the sun takes place, then the atmo- 

 sphere" must also be heated to a greater extent, and 

 consequently more intense up-currents of warm air 

 are formed, resulting in more pronounced low-pressure 

 areas. There must, however, be a compensating 

 effect somewhere, and this is found on the opposite 

 side of the earth when the previously heated air 

 arrives, descends, and creates an area of excess 

 pressure. ^ , 



This backward and forward transference ot air 

 becomes, therefore, of great importance in studying 

 the weather changes in any one region, because the 

 rainfall phenomena are so closely related to the 

 pressure changes. 



Away from the middle portions of those two large 

 areas which behave in this see-saw manner, the varia- 

 tions of pressure should, and actually do, have a 

 different periodic nature. It is of extreme import- 

 ance therefore, when trying to trace the sun s action 

 on our atmosphere, to separate the regions over which 

 the variations may be truly solar from those which 

 exhibit variations modified by the mechanism of the 

 atmosphere itself. 



There is therefore no reason why we should take a 

 pessimistic view of the attempts made to solve this 

 fascinating riddle of the relationship between changes 

 of solar activity and the vagaries of the weather. 

 \n enormous amount of accumulated material is ready 

 for discussion, and efforts should be made to secure 

 the continuity of these observations and at the same 

 time to coordinate the data along lines most suitable 

 for this particular research. 



William J. S. Lockyer. 



THE SURVEY OF INDIAN 



THE extracts from the narrative reports of the 

 Survey of India for the years 1902-3 are con- 

 tained in a thin and attenuated volume of some eighty 

 pages, which, as compared with previous reports, re- 

 presents the effects of Indian financial economy 

 applied to one of its most interesting departments. 



1 " Extracts from the Narrative Reports of the Survey of India for the 

 Season 1902-3." (Calcutta : Government Printing Office, 1905.) Price 2s. 3rf. 



