OPTICAL PHENOMENA. 527 



Australis, the southern day-break. Its appearance, however, is far from being so common 

 as in the northern zone, and is much less imposing. Don Antonio Ulloa, off Cape Horn, 

 in the year 1745, witnessed the first appearance of the kind upon record in this region. 

 Upon the clearing off of a thick mist, a light was observed in the southern horizon, 

 extending to an elevation of about thirty degrees, sometimes of a reddish colour, and 

 sometimes like the light which precedes the rise of the moon, but occasionally more bril- 

 liant. Captain Cook, in the same latitudes, had more distinct views of the luminous 

 streamers adorning the night-sky of the south. In the course of his second voyage he 

 remarks, that on February the 17th, 1773, "a beautiful phenomenon was observed in the 

 heavens. It consisted of long colours of a clear white light, shooting up from the horizon 

 to the eastward, almost to the zenith, and spreading gradually over the whole southern 

 part of the sky. These columns sometimes bent sideways at their upper extremity ; and 

 though in most respects similar to the northern lights, yet differed from them in being 

 always of a whitish colour, whereas ours assume various tints, especially those of a purple 

 and fiery hue. The stars were sometimes hid by, and sometimes faintly to be seen 

 through, the substance of these southern lights, Aurora Australis. The sky was generally 

 clear when they appeared, and the air sharp and cold, the thermometer standing at the 

 freezing point, the ship being in latitude 58 south. 



The history of auroral phenomena goes back to the time of Aristotle, who undoubtedly 

 refers to the exhibition in his work on meteors, describing it as occurring on calm nights, 

 having a resemblance to flame mingled with smoke, or to a distant view of burning 

 stubble, purple, bright red, and blood-colour, being the predominant hues. Notices of it 

 are likewise found in many of the classical writers ; and the accounts which occur in the 

 chronicles of the middle ages, of surprising lights in the air, converted by the imagination 

 of the vulgar into swords gleaming and armies fighting, are allusions to the play of the 

 northern lights. There is strong reason to believe, though the fact is perfectly inscrutable, 

 that the aurora has been much more common in the European region of the northern 

 zone, during the last century and a half, than in former periods. A very brilliant 

 appearance took place on the 6th of March 1716, which forms the subject of a paper by 

 Halley, who remarks, that nothing of the kind had occurred in England for more than 

 eighty years, nor of the same magnitude since 1574, or about 140 years previous, in the 

 reign of Queen Elizabeth, when Cambden and Stow were eye-witnesses of it. The latter 

 states in his Annals, that on November 14th, "were seen in the air strange impressions of 

 fire and smoke to proceed forth from a black cloud in the north towards the south 

 that the next night the heavens from all parts did seem to burn marvellous ragingly, and 

 over our heads the flames from the horizon round about rising did meet, and there double 

 and roll one in another, as if it had been in a clear furnace." The year following, 1575, 

 it was twice repeated in Holland, but not observed in this country ; and as a specimen of 

 the tone of thought respecting the aurora, the description of Cornelius Gemma, a pro- 

 fessor in the university of Louvain, may be given. Referring to the second instance of 

 the year, and speaking in the language of the times, he remarks : " The form of the 

 Chasma of the 28th of September following, immediately after sunset, was indeed less 

 dreadful, but still more confused and various ; for in it were seen a great many bright 

 arches, out of which gradually issued spears, cities with towers and men in battle array ; 

 after that, there were excursions of rays every way, waves of clouds and battles 

 mutually pursued and fled, and wheeling round in a surprising manner." This phenomenon 

 was repeatedly observed in the last century in Sweden, as at present ; but prior to the 

 year 1716, the inhabitants of Upsal considered it as a great rarity. Nothing is more 

 common now in Iceland than the northern lights, exhibited during the winter with im- 

 posing grandeur and brilliance : but Torfaeus, the historian of Denmark, an Icelander, who 



