Appendix D. AURORAL APPEARANCES. 385 



the Aurora borealis in the northern temperate zone, and during the 

 Antarctic expedition was in the habit of recording in the log- 

 book the appearance presented by the Aurora australis. The late 

 Mr. "Williams, Mr. Haddon, and Mr. Theobald, who were also 

 witnesses of the appearances on this occasion, considered it a brilliant 

 display of the aurora. 



Feb. lUli, 9 p.m.— Bar . Corr. 29751 ; temp. 62°; D. P. 410° ; 

 calm, sky clear ; moon three-quarters full, and bright. 



Observed about thirty lancet beams rising in the north-west from 

 a low luminous arch, whose extremes bore W. 20° S., and N. 50° E. ; 

 altitude of upper limb of arch 20°, of the lower 8°. The beams 

 crossed the zenith, and converged towards S. 15° E. The extre- 

 mity of the largest was forked, and extended to 25° above the 

 horizon in the S.E. by S. quarter. The extremity of the- centre one 

 bore S. 50° E., and was 45° above the horizon. The western beams 

 approached nearest the southern horizon. All the beams moved and 

 flashed slowly, occasionally splitting and forking, fading and bright- 

 ening ; they . were brightly defined, though the milky way and 

 zodiacal light could not be discerned, and the stars and planets, 

 though clearly discernible, were very pale. 



At 10 p.m., the luminous appearance was more diffused ; upper 

 limb of the arch less defined ; no beams crossed the zenith ; but 

 occasionally beams appeared there and faded away. 



Between 10 and 11, the beams continued to move and replace 

 one another, as usual in auroras, but disappeared from the south-east 

 quarter, and became broader in the northern hemisphere ; the longest 

 beams were near the north and north-east horizon. 



At half-past 10, a dark belt, 4° broad, appeared in the luminous 

 arch, bearing from N. 55° W. to N. 10° W. ; its upper limb was 10° 

 above the horizon : it then gradually dilated, and thus appeared to 

 break up the arch. This appeared to be the commencement of the 

 dispersion of the phenomenon. 



At 10.50, p.m. the dark band had increased so much in breadth that 

 the arch was broken up in the north-west, and no beams appeared 

 there. Eighteen linear beams rose from the eastern part of the arch, 

 and bore from north to N. 20° E. 



Towards 11 p.m., the dark band appeared to have replaced the 



VOL. II. C C 



