SUNSPOTS AND VOLCANIC AND SEISMIC PHENOMENA. 65 



and eruptions, when acting in conjunction with other 

 influences. 



(5) Earthquakes are most prevalent in years of notoriously 

 cold winters, and more frequent in winter than in summer 

 as far as Europe is concerned. The years 1811-12, 1846, 

 1855-56, 1880-81, and 1889, which were all years of maxi- 

 mum winter frost in England and Europe, and periods of 

 drought in various parts of the world, were also noted for 

 violent seismic and volcanic disturbances. 



(6) It has often been pointed out that a certain corres- 

 pondence exists between the occurrence of droughts and 

 earthquakes, red rain and earthquakes and eruptions, and 

 usually these events occur contemporaneously at sunspot 



Part II. — On the Connection between Sunspot and 

 Meteorological Phenomena. 



SYNOPSIS : 

 I. Cause of Sunspots. 

 II. Sunspots and Temperature. 



III. Sunspots and Barometric Pressure. 



IV. Sunspots and Rainfall. 



V. Sunspots, Earth-magnetism and Solar Corona. 

 VI. Index to Literature. 

 VII. Appendices. 



I. Cause of Sunspots. — Various theories have been 

 advanced to account for sunspots. Some of these are 

 intimately bound up with the various hypotheses to account 

 for the sun's maintenance of his own heat. They might 

 briefly be summarised as follows. They are caused by 



(1) Meteoric swarms, a hypothesis bound up with the 

 meteoric theory to account for the sun's heat. 



1 " Possible connection between Sunspot Minima and Earthquakes and 

 Volcanic Eruptions," by H. I. Jensen — Proc. Roy. Soc. of N.S.W., xxxvi., 

 June 4th, 1902. 



2 " Periodicity of G-ood and Bad Seasons," by H. C. Russell — Proc. Roy. 

 Soc. of N.S.W.,xxx., June 3rd, 1896; and Professor David's discussion on 

 Mr. Russell's paper. 



E-Junel 1904. 



