Number limited to Finland only small.
The number limited to Finland, for which hitherto corresponding observations from other lands are wanting, is very small—212, or 19 per cent. of the whole number seen in Finland. With the increase of frequency of the phenomena at the time of maximum, the number observed in Finland and America on the same day increases; while those observed in Finland and Europe only, or in Finland only, decreased, in accordance with the known law that with the frequency the intensity and extent also increase.
One third of Auroræ seen in America and Europe simultaneously.
Between 1826 and 1855, of 2878 days on which, in America, the Northern Lights were seen, there were 1065 on which they were also visible in Europe; so that at least every third day of Auroræ was common to both these portions of the globe. In the years 1846 to 1855, and 1868 to 1872, there were in the first period 657 Northern-Light days common to America and Europe out of 1691, and in the second 397 out of 715.
Local occurrence of the Aurora not in favour of its assumed cosmical nature.
The comparison by Prof. Fritz of M. Moberg’s Finland observations has been lately reviewed in ‘Nature’ (March 8, 1878) and the result arrived at that, “After ten years, in spite of the vastly accumulated material of careful observations, there appears no necessity to change Herr Fritz’s system of curves in any essential detail; indeed certain parts of the same, which were at first only based on probability and supposition (the part of the principal zone between the north of Norway and Nishen Kolynisk as an instance), we now know with perfect certainty to be correct.” It has been remarked that the local occurrence of Auroræ is not in accordance with the hypothesis of the phenomenon being one of a cosmical nature.
The winter of 1870 was remarkable for brilliant displays; and the displays of October 24th and 25th, 1870, were remarkably brilliant in England and in America also, and the Aurora Australis was seen on the same days at Madras. These displays were seen in England and America in the daytime as patches or coronæ of white light, with streamers stretching upward from them.