Feb. 2 2, 1872] 



NATURE 



323 



given, from Worcester we learn that it was noticed " shortly 

 before 6 o'clock in the twiliglit, when thin fleecy clouds of a 

 bright rose colour were observed in the South and East," whilst 

 correspondents al 'Ca& Kolnische Zeitung state that it was first 

 noticed at Cologne about 6 o'clock, and at Bonn about "half- 

 past 5> gradually becoming more and more marked till 6 

 o'clock, when do doubt was left as to its true auroral character." 

 While there is thus clear evidence that the phenomena had 

 commenced some time before 5 o'clock, there is, as might 

 be expected, great diversity as to the time when it was last 

 visible. That this should be the case is only natural, and is 

 entirely dependent on purely local circumstances — the state of 

 the weat'ner, the cloudiness of the sky, &c. Thus, whilst in 

 some the aurora first appeared at 6 o'clock, to others it was not 

 visible till between 7 and S ; and whilst in some places it 

 disappeared about S or 9, it was then in others in its most 

 brilliant state. But, taken as a whole, it appears to have lasted 

 the whole evening until quite late at night ; thus a correspondent, 

 writing to the Pall Mall Gazette from Autun, states that ' ' at mid- 

 night the East was crimson, and it was so light that I could tell 

 the time easily, although my w.itch has gold fingers, and strong 

 shadows were cast in rooms whose windows faced the East." 



We have thus evidence of the aurora having commenced about 

 5 o'clock, and continuing at least till midnight, and probably 

 later. But before proceeding to notice the other attendant phe- 

 nomena, we would direct attention to a passage in the letter of the 

 correspondent of the Pall Mall Cazdtc, before alluded to, which 

 confirms the hypothesis that the accounts of "showers of blood," 

 &c., mentioned in ancient chronicles were in reality only auroral 

 displays. He writes, " all these signs and wonders produced a 

 considerable effect upon the peasantry, who see in them warn- 

 ings of a coming war ; they always connect the idea of a red 

 aurora with bloodshed." Comparing, then, all the varied 

 accounts to which we have referred, we find very general agree- 

 ment with regard to certain phenomena, some of which are of 

 very remarkable character. Thfe first of these is that when the 

 aurora was noticed by those who ob erved it early in the evening, 

 it appeared m the Southern and South- Western horizons, thence it 

 seems gradually to spread, and finally appeared later on in the 

 evening in the Northern and Eastern horizon. That this was the 

 case is shown by the agreement of the accounts, some of which we 

 have already quoted, and manymore of whichmightbegiven. Thus 

 at Bonn, "nothing remarkable was to be noticed on the northern 

 horizon, whilst on the southern lay the dense, greyish bank of 

 clouds, whence auroral streamers shortly ascended." There can 

 also be little doubt that during the middle of the evening, and 

 towards midnight the chief seat of the display was to the north 

 and east, as shown in the letters of those who first observed the 

 phenomena at about 7.30 to 9 o'clock, and continued to do so 

 till towards midnight. The second well-marked phenomenon 

 was that between 7 and 8. There appeared a brilliantly-coloured 

 arch, extending across the heavens from S.W. towards the north 

 and east. Thus at Autun ^e have described " a splendid and 

 perfect arch, spanning the sky from a point on the south-eastern 

 horizon to one on the south-western, and which lasted, more or 

 less continuously, for two hours, whilst from to to 12 the sky 

 became gradually less luminous in the south, and grew more and 

 more splendid overhead. Till about 11 the two eastern and 

 western auroras united in a vast arch overhead, with tongues of 

 green flame darting through a suffused crimson." Similarly other 

 accounts, with merely local variation. The third well-marked 

 phenomenon appears to have been the formation of a " corona," 

 nearly, if not quite, in the zenith, whence auroral rays streamed 

 out in all directions. At some places this was more marked than 

 at others, but is more or less universally noticed, both by English 

 and foreign observers. Thus at Cardiff it is reported that "a 

 corona, having rugged, sharply-defined edges, stood out promi- 

 nently in the zenith, apparently on a parallel plane to the earth, 

 and having its centre almost immediately over the head of the 

 spectator, rays from which extended to the N.E, and N,W. 



horizons." If one'may venture to say so, most aurorn; visible 

 in our latitudes appear to commence in general by an accumula- 

 tion of cloud masses towards the magnetic north, then coloured 

 masses slowly appear, and afterwards rays, or streamers, are sent 

 up from this northern horizon towards the zenith. Sometimes 

 the coloured masses themselves rise toward the zenith, and there 

 the streamers pass in all directions. But in this aurora of the 

 4th of February, all the most marked phenomena are directly con- 

 trary to our ordinary experience, and should therefore be carefully 

 noted. It is an extremely interesting inquiry to ascertain 

 whether on the evening of the 3rd or 4th instant a brilliant 

 Aurora Australis was visible in the southern hemisphere. If we 

 consider the wide extent of country over which the aurora which 

 we are describing was visible, the probability becomes very great 

 that this will be found to be the case. The question then arises. 

 Was the aurora of Feb. 4th, appearing as it did first in the 

 southern horizon, an Aurora Australis or not? It is impossible 

 to answer this question definitely ; but we would throw out the 

 following suggestion : — Knowing the ultimate connection that 

 there is between northern and southern aui or3>, and the fact that 

 one of any magnitude rarely happens without the other, may we 

 not have seen the last traces of a grand Aurora Australis, which 

 gradually died away, whilst at the same time an Aurora Borealis 

 was in process of formation, and which appeared in its fidl 

 brilliancy in the northern and eastern hori zon towards the latter 

 part of the evening ? We would make this suggestion with all 

 due deference, but it seems to us to account in a fairly satisfactory 

 manner for most of the very unusual and peculiar phenomena 

 noticed, viz., the first appearance of the aurora in the south, the 

 grand arch, the corona in the zenith, and the final disappearance 

 in the north. \\'e must also remember that in what is called the 

 correspondence of northern and southern aurorce, there must be 

 at least twelve hours difference as regards time. So that if there 

 was an Aurora Australis on the same day, it would be dying out 

 at the time our display was commencing. 



In conclusion, the wide extent of country over which this 

 aurora of the 4th February was visible, is easily shown. In 

 Paris a " magnificent aurora" is reported, at Nancy and Chau- 

 mont there was a " brilliant display," while the Franco-German 

 telegraph lines were greatly disturbed. At Constantinople one 

 telegram states that " a splendid aurora, extending over half the 

 heavens, was visible for several hours ; " whilst another states 

 that it was seen "from 10 till half-past i." From Alexandria 

 we hear that " a large space of the skies was illuminated for five 

 hours." That it was visible at JMalta, Suez, and Bombay, the 

 following interesting account shows. It is supplied by Mr. George 

 Draper, of the British Indian Submarine Telegraph Company, 

 under date of Feb. 5th, audit also shows how powerful were the 

 " earth currents " which were noticed in connection with this 

 most brilliant aurora. He writes : — 



" It may interest your readers to know that the brilliant aurora 

 which was visible in London last night was also visible at Bom- 

 bay, Suez, and Malta. Our electrician at Suez reports that the 

 earth currents there were equal to 170 cells (Uaniell's batteries), 

 and that sparks came from the cable. These electrical disturb- 

 ances lasted until midnight, and interrupted the working of both 

 sections of the British Indian cable between Suez and Aden, and 

 Aden and Bombay. Since Thursday last the signals on the 

 British Indian cables have been very much interfered with by 

 electrical and atmospheric disturbances, causing considerable 

 delay in the transmission of messages, which all efforts failed 

 entirely to overcome. Our superintendent at Malta also reports 

 that there was a very severe storm there yesterday morning, so 

 much so that they were compelled to join the cable to earth for 

 several hours. He also reports the aurora as very large and 

 brilliant. The electrical disturbances on the cables in the Medi- 

 terranean, and on those between Lisbon and Gibraltar, and Gib- 

 raltar and the Guadiana, were also very great. The signals on 

 the land line between London and the Land's End were inter- 

 rupted for several hours last night by atmospheric currents, " 



