SOLAR CHANGES OF TEMPERATURE. 188 



This, as Avc have already pointed out, is precisely what happened 

 after the abnormal + heat pulse of 1892, following- close upon the 

 condition of solar mean temperature. 



The widened line curves, instead of crossing, according to the few 

 precedents w^e have, in 1897 or 1898, have not crossed yet — that is, the 

 condUion of ordinary" solar mean temperature has not even yet been 

 reached. 



We have shown that, as a matter of fact, in a normal cycle India is 

 supplied from the southern ocean during the minimum sun-spot period 

 and that this rain is due to some pressure effect brought about in high 

 southern latitudes by the sun at — temperature. 



As the — temperature condition was not reached in 1899, as it would 

 have been in a normal 3"ear, the rain failed. 



We may say then that the only abnormal famine recorded since 1836 

 occurred precisely at the time when an abnormal effect of an unpre- 

 cedented maximum of solar temperature was revealed by the study of 

 the widened lines. * * * 



NOTE BY MR. I.ANGLEY. 



We find that in the charts certain lines, whose character is to us 

 unknown, reach their maximum at the same time that the sun spots 

 do, while another class of lines, which are known, attain their mini- 

 mum at the same time. 



It may not at first be entirely clear to the general reader how our 

 knowledge or our ignorance can appear as active factors in determin- 

 ing the position of lines in the sun, as they seemingly do, but the 

 paradox is easily explained when we notice that the lines of which we 

 are ignorant are those which are associated at such high temperatures 

 that we can not observe them, while those which we know, are dis- 

 associated at temperatures which bring them within the range of the 

 means in our laboratories. 



This, then, is the simple explanation of this most interesting, Itut 

 at first sight paradoxical, observation of Mr. Lockj^er. 



In the plate annexed (PI. I) the upright lines are one year apart in 

 every case; the upper curve is that showing the increase and decrease 

 of the spots on the sun. Thus, in 1883, the sun spots had reached the 

 greatest display at that time shown by the altitude of the curve, after 

 which they ran down, reaching their smallest amount very nearly 

 seven years later — about 1889 — and then mounting again until, in 

 1893, they had again reached their maximum value, which was indeed 

 higher than the previous one. 



Now, if we look immediately under them in the same years when 

 these were at a maximum, we shall see that the irregular lines, which 



