SUNSPOT MINIMA AND VOLCANIC ERUPTIONS. 55 



get an entire space, are given a half. Only Krakatoa and 

 Bandaisan are alloted three spaces each. In other places 

 where large columns of three or four spaces appear, they 

 are composed of several severe (or widespread) eruptions 

 or earthquakes. 



The earthquakes are numbered (with a few exceptions), 

 and the eruptions lettered. I do not deem it necessary to 

 describe the eruptions or earthquakes of each group, but 

 an index to the chart is appended. Eruptions of Vesuvius 

 are lettered V, those of Etna E, those of the Sandwich 

 Islands K, and so on. As regards earthquakes the same 

 numbers are used again in each group but with no special 

 significance. 



The sunspot curve has been taken with Mr. Russell's 

 permission, from his paper 1 on "The Periodicity of Good 

 and Bad Seasons," but it is inverted so as to bring the 

 minima on top. The part of the curve between 1892 and 

 1902, I constructed myself from data obtained in " The 

 Observatory" for 1898, and the Journ. Royal Astron. Soc. 

 Fine solar coronse are seen at every sunspot minimum. 

 These are denoted on the chart by columns placed under the 

 sunspot curve. In 1882-3 there was a very extensive 

 corona, accompanied however by some prominences of great 

 magnificence. 



The most noticeable instances of seismic phenomena not 

 coinciding with the groups are — (1) Earthquakes of import- 

 ance in 1815, 1828-9, 1840, 1847-8, Mendoza 1861. (2) 

 Eruptions in 1829, 1840, 1847, 1870-2. In the index are 

 enumerated all the earthquakes and eruptions for each 

 year since 1780. 



The following table gives all the eruptions of Vesuvius, 

 Etna, (and of a few other sensitive spots) that are reported 



1 Journ. Koy. Soc. N. S. Wales, xxx., 1896, p. 70. 



