6o 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 70 



These isopleths give a very clear presentation of the distribution 

 of the temperature variation as well for the places as for the 

 times. There is well marked agreement between them. We find 

 that the great minimum in the years 1903 and 1904 both in the first 



J7-38'N- 



Figure 28. Curves for the surface temperature for 10° longitude fields 

 between 10° and 40° west longitude and between 27° and 45° north latitude, 

 February, 1898 to 1910. 



and in the second decade group is strongly indicated, also the 

 smaller minimum in the year 1899, particularly strongly indicated in 

 the first decade group. Both the first and the second maximum 

 periods are distinctly indicated. The difference between the western 



