December 14, 1900.] 



SCIENCE. 



915 



phoid bacillus or any specific forms other 

 than B. coli communis. For obvious reasons 

 it is inadvisable at this time to give this 

 phase of water analysis any detailed con- 

 sideration. 



SUNSPOTS AND RAINFALL.* 

 At the meeting of the Royal Society on 

 November 22d, Sir Norman Lockyer and 

 Dr. W. J. S. Lockyer presented a paper on 

 ' Solar Changes of Temperature and Varia- 

 tions in Rainfall in the Region Surround- 

 ing the Indian Ocean. ' 



Sir Norman Lockyer, who made the 

 communication, said the fact that the ab- 

 normal behavior of the widened lines in the 

 spectra of sunspots since 1894 had been ac- 

 companied by irregularities in the rainfall 

 of India, suggested the study and correla- 

 tion of various series of facts that might be 

 expected to throw light on the matter. 

 Among the conclusions thus arrived at 

 were: (1) A discussion of the chemical 

 origin of lines most widened in sunspots at 

 periods of maxima and minima indicated a 

 considerable rise above the mean tempera- 

 ture of the sun around the years of sunspot 

 maximum, and a considerable fall around 

 those of sunspot minimum. (2) From the 

 facts of rainfall in India (during the south- 

 west monsoon) and Mauritius between the 

 years 1877 and 1886, as given by Blanford 

 and Meldrum, the effects of these solar 

 changes were seen to be felt in India at 

 sunspot maximum and in Mauritius at sun- 

 spot minimum, the greater efifect being in 

 Mauritius. The pulse in Mauritius at sun- 

 spot minimum was also felt in India, giving 

 rise generally to a secondary maximum. 

 India, therefore, had two pulses of rainfall, 

 one near the maximum and the other near 

 the minimum of the sunspot period. (3) 

 The dates of the beginning of these two 

 pulses in the Indian and Mauritius rainfall 

 were related to the sudden remarkable 

 * From the London Times. 



changes in the behavior of the widened 

 lines. (4) All the famines recorded in the 

 Famine Commission reports as having de- 

 vastated India during the last half-century 

 occurred in the intervals between these two 

 pulses. (5) Investigation of the changes 

 in (a) the widened lines (6) the rainfall of 

 India, and (c) the rainfall of Mauritius 

 during and after the last maximum in 1893 

 showed in all three important valuations 

 from those exhibited during and after the 

 last maximum of 1883. The minimum of 

 1888-89 resembled the preceding minimum 

 of 1878-79. (6) From 1849-1878 the low- 

 est Niles recorded occurred between the 

 same intervals. (7) Although the rela- 

 tions of these intervals to the droughts of 

 Australia and of Cape Colony, and to the 

 variations of rainfall in extra- tropical re- 

 gions generally, had not been investigated, 

 a general agreement had been made out 

 between the intervals and the rainfall of 

 Scotland, and both pulses had been traced 

 in the rainfalls of Cordoba and the Cape of 

 Good Hope. (8) The results of the in- 

 quiry having been placed before Mr. John 

 Eliot, Meteorological Reporter to the In- 

 dian Grovernment, he gave it as his opinion 

 that they accorded closely with all the 

 known facts of the large abnormal features 

 of the temperature, pressure, and rainfall 

 in India during the last twenty-five years, 

 and that hence the inductions already ar- 

 rived at would be of great service in fore- 

 casting future droughts in India. 



When the image of a sunspot was thrown 

 on the slit of a spectroscope, examination 

 of the spectrum indicated that the blackness 

 of the spot was due not only to general but 

 also to selective absorption, and that the 

 lines widened by the selective absorption 

 varied from time to time. From many 

 years' observations of these widened lines 

 it appeared that at some periods they were 

 distinctly traceable to known elements, 

 while at others their origins had not been. 



