1902.] A Short Period of Solar and Meteorological Changes. 501 



external or extra-terrestrial action, is considerably strengthened by an 

 examination of the pressure-curve of a very distant station, such as 

 Cordoba. Dealing with the pressure of Cordoba during the high-pressure 



WIDENED LINE 

 CROSSINGS. 



+20 



MEAN LATITUDE+io°- 

 OF 



SUNSPOTS. 



LATITUDE OF 

 TOTAL 

 SPOTTED AREA. 







-10' 



NUMBER OF 

 PROMINENCES. 100- 

 



PRESSURE . 



BOMBAY. .9000 

 [OCT. — MAR.] 



29 '8600 



PRESSURE. 600 



BOMBAY. 

 [APR.- SEPT.] 



29-7000 



300 



1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 • * 1 * 1 •• 1 



1860-0 1870-0 1680-0 



Fig. 1. 



1 1 1 1 1 1 . , 1 . 

 1890-0 1900-0 



months, April to September, the curve (fig. 2, Curves F and E), represent- 

 ing the variation from the mean from year to year, is exactly the inverse 

 of the curve representing the Bombay and other Indian pressures for 

 the same months over the same period of time. The cause, therefore, 

 which raises the mean value for the low-pressure months over the 

 Indian area would appear to lower the mean value of high-pressure 

 months at Cordoba simultaneously. In fact, we have a see-saw. 



4. Further investigation shows that not only do the pressures of 



