O'Reilly — On the Dates of Volcanic Eruptions. 403 



3. " This period of subterranean disturbance stands in an inverse 



ratio with a period of similar length with reference to sun- 

 spots and terrestrial magnetic variations, so that the years 

 in which the sunspots are maxima, and in which the 

 amount of the magnetic variation is also a maximum, are 

 in general poor in volcanic phenomena and earthquakes, and 

 inversely so. 



4. " Not only certain years, but also certain days of the year, seem 



to be more connected with eruptions than others, and 

 moreover seem further to be signalized by the occurrence of 

 remarkable cosmical phenomena." 



Here follow ten other conclusions referring to " Synchronisms and 

 Antagonisms," &c., covering pp. 85 to 99 of the work, into the con- 

 sideration of which it would be out of place here to enter. 



It would seem that the complete list of eruptions spoken of by 

 Kluge in his two Papers was not published, and I have not been able 

 to find any trace of such publication subsequent to 1863. 



Geikie also refers, in the note on p. 183, to the Paper by Poey 

 (Comptes. Eend. LXXYIII., 1874, p. 51), wherein he points out the 

 relation between certain of the eruptions cited by Kluge and the sun- 

 spot period, but so briefly that I think it desirable to point out more 

 in detail the essential points of Poey's paper or papers, and their bear- 

 ing on the question of the connection observable between volcanic 

 eruptions and the sun-spot period. 



The first paper (as indeed tlie two others which follow) appears as 

 a letter to the Secretary of the Academy of Sciences, Paris : — "On 

 the Relations between the Sun-spot Period and the Hurricanes of the 

 Antilles, of the IST. Atlantic and of the Southern Indian Oceans."^ He 

 utilises Meldrum's Paper which appeared on this subject in "Nature " 

 (9th October, 1873, p. 495), and gives a table of some extent 

 showing the relation between the 357 hurricanes of his catalogue and 

 the sun-spot periods. He remarks : — 



" It may be noted that the most of the years of maxima of hur- 

 ricanes fall at an interval of from six months to two years after the 

 years of maxima of sunspots. There may also be observed a "lag'^ 

 as regards the period of the magnetic variation, aurorse boreales, 

 severe winters and other meteorological phenomena. 



Poey discusses several points in connection with the table — shows 



1 Compt. Eend., 1878, vol. Lsxvii., p. 1222. 



