196 



0.\ THE PERIODICITY OF THE AURORA BOREAUS. 



GENERAL CATALOGUE OF AURORAS. Com 



Tear 

 1569 

 1071 

 1572 

 1573 

 1574 

 1575 

 1576 

 1577 

 1580 

 1581 

 1584 

 1585 

 1586 

 1588 

 1589 

 1590 

 1591 

 1592 

 1593 

 1596 

 1599 

 1600 

 1602 

 1603 

 1 605 

 1606 

 1607 

 1608 

 1G09 

 1612 

 1614 

 1 6 1 5 

 1621 

 1622 

 1 623 

 1024 

 1G25 

 1626 

 1627 

 1628 

 1029 

 1630 

 1032 

 1033 

 1G34 

 1037 

 1638 

 1040 



Jan. 



Apr. 



' 



June | July j Aug. 



i 





Oct. 



Not. 



l 

 5 



2 



9 



1 



'.) 

 8 

 1 

 2 

 1 

 5 

 1 

 3 

 1 

 1 

 7 

 1 

 1 

 1 

 1 

 2 



1 

 1 

 2 

 1 

 1 

 1 

 5 

 2 

 7 

 3 

 4 

 

 2 

 7 

 14 

 4 

 1 

 3 

 3 

 1 

 1 

 1 



