HUMPHREYS: PRODUCTION OF CLIMATIC CHANGES 



369 



Discrepancies Between Average Temperatures and Sun-Spot Numbers 



NATURE or 

 DISCREPANCY 



1755-56 

 1766-67 



1778-89 



1784-85-86 



1799 

 1809 



1812-13-14-15-16 



1831-32 



1856-57 

 1872-73 



1875-76 

 1884-85-86 



1890-91-92 

 1902-03-04 



1912-13 



Cold 

 Cold 



Warm 



Cold 



Cold 

 Cold 



Cold 



Cold 



Cold 

 Cold 



Cold 

 Cold 



Cold 

 Cold 



Cold 



PROBABLE CAUSE 



Kotlugia, Iceland, 1755. 



Hecla, Iceland, 1766. 

 Mayon, Luzon, 1766. 



Maximum number (annual) of sun-spots ever e- 

 corded and unusually short spot period. Can 

 it be that the solar constant actually was dis- 

 tinctly greater than usual at th's time? 



AsAMA,! Japan, 1783. The most frightful erup- 

 tion on record. 

 Skaptar JokuU, Iceland, 1783. 

 Vesuvius, Italy, 1785. 



Fuego (?), Guatemala. (Uncertain.) 



St. George (?), Azores, 1808. (Uncertain.) Etna(?), 

 Sicily, 1809. (Uncertain.) 



Soufriere, St. Vincent, 1812. 



Mayon, Luzon, 1814. 



Tomboro, Sumbawa, 1815, very great. 



Graham's Island, 1831. 

 Babujan Islands, 1831. 

 Pichincha, Ecuador, 1831. 



Cotopaxi (?), and others, 1855-56. (Uncertain.) 



Vesuvius, Italy, 1872. 

 Merapi, Java, 1872. 



Vatna JokuU, Iceland, 1875. 



Krakatoa, Straits of Sunda, 1883, greatest since 



1783. 

 Saint Augustin, Alaska, 1883. 

 Tarawera, New Zealand, 1886. 



Bogoslof, Aleutian Islands, 1890. 

 Awoe, Great Sangir, 1892. 



Pele, Martinique, 1902. 

 Santa Maria, Guatemala, 1902. 

 Colima, Mexico, 1903. 



Katmai, Alaska, 1912. 



Capitals indicate exceptional violence. 



