32 
MR. C. C. CHRISTIE ON THE AURORA BOREALIS 
while the paleness of the light and the absence of noise gave it a spectral and un- 
earthly character, which was very striking. The gusts of wind increased the illusion. 
(See Sketch 2. Plate II.) 
9 h 20 m . — The arch becoming very irregular ; a large indentation on the eastern 
side, thus : 
Fig. A. 
The pseudo-flames have almost entirely subsided ; they still exhibit the same ap- 
pearance of burning, but in a steadier manner. 
The centre of the arch is about equidistant from y Ursse Majoris and a Lyree. 
9 h 25 m . — The western extremity suddenly blazed up ; one very broad pencil of 
rose-coloured light forming the western boundary to the rest ; through it a Aquilse 
shone with great brilliancy. All these westerly pencils perfectly straight, of greater 
altitude, and of a more defined and steady light than the easterly. Extremely narrow 
brilliant jets of light issuing from the central part, and having their base in the midst 
of the dark cloud. (See Sketch 3. Plate III.) 
9 h 2 7 m . — Arch dilapidated. (See Sketch 4. Plate III.) 
9 h 30 ra . — Arch entirely broken up. 
9 h 35 m . — The arch restored, but of an irregular undulating form, thus : 
Fig. B. 
The light fainter, as also the pencils which continue to rise from every part, but 
more distinctly from the two extremities. 
9 h 55 m . — The arch much depressed, and in form thus : 
Fig. C. 
The cloud below much darker, the pencillings very faint. 
1 0 h 20 m . The arch strongly defined and steady ; but occasional gleams, as of the 
vapoury light rising in a body simultaneously from the whole extent of it. The 
cloud verv dark, and of this form : 
Fig. D. 
1 regret that I was unable to wait for the total disappearance of the phenomenon, 
though for nearly an hour there had been no promise of any fresh display. 
Note. — By the term arch is indicated the under surface of the body of light. 
