1 86 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. JO 



three or four short periods in the first sun spot period of the figure, 

 four periods in the second, and three in the third sun spot period. 

 The last three short periods fall very well with corresponding 

 periods in the variation of the prominences and particularly in the 

 disturbances of the magnetic elements. The sun spot curve shows 

 also an indication of the same three periods. In the sun spot period, 

 1889 to 1902, the agreement between the storm curve and particu- 

 larly the magnetic curve is not very good. In the sun spot period 

 of 1878 to 1889 the storm curve and the prominence curve agree, 

 but the variations in the prominences come later on than the varia- 

 tions in the storminess. At the storm maximum in the year 1880 

 there is nothing corresponding in the other curves. On the whole 



Figure 64. St : storminess in the northern United States according to 

 Kullmer. P: average daily number of prominences according to the observa- 

 tions in Rome to 1898 and Catania. M : degree of disturbance of the three 

 magnetic elements at Potsdam. S : observed relative sun spot numbers 

 according to Wolfer. 



the storminess in this eleven-year period appears to be much less 

 than it should be in comparison with the prominences and sun spots. 

 Kullmer's investigations on the variations in storm tracks and 

 storminess have furthermore led Huntington to the view that the 

 variations in the storminess on the earth are the cause of the varia- 

 tions of.the temperature on the surface of the earth. He assumes that 

 an increased storminess would cause the temperature to fall, par- 

 ticularly in the warmer regions of the earth, because the warm air 

 from lower latitudes would be carried by the storms to higher lati- 

 tudes and there would rise above the colder air at the earth's sur- 

 face. This colder air would then displace the warmer air at lower 

 latitudes and partly by vertical circulation the warmth continually de- 

 veloped at the earth's surface would penetrate to the higher layers 

 of the air. Huntington considers that this influx of greater quanti- 



