322 
DAY AURORA. 
coalescing at their tases, these radiating processes aug- 
mented the size of the central segment. The inter- « 
vals between them appeared, by contrast, to be artifi- 
cially illuminated. 
" Till now there had been no movement ; but at 
llh. 20m. these cloud-like processes or radiations strik- 
ingly resembled the rays or beams of a coruscating 
auroral arch. Dr. Vreeland and myself witnessed re- 
peatedly interruptions of their continuity; then sud- 
den shootings out, or increasings of their length ; and 
then a rapid and momentary formation, followed by a 
sudden and complete disappearance. 
"At this time, too, a strange wavy movement was 
seen about the shorter prolongations in the neighbor- 
hood of the vertex of the mass. These resembled the 
rising wreaths of 'frost-smoke' seen in Wellington 
Channel, and had an appearance almost of combus- 
tion. 
" During all these phases, the cloud-like character 
was singularly preserved : the rays appeared to modi- 
fy the processes, as light would behind our ordinary 
clouds. The whole exhibition was a daylight one, 
perfectly cloud-like, differing only in the elements of 
shape, movement, and radiated illumination. It was 
a day aurora. 
The appearance continued until twenty minutes of 
meridian. At llh. 10m., when it was at its maxi- 
mum, the rayed prolongations stretched nearly across 
the sky ; and the centre of the mass from which they 
emanated was fifteen degrees west from the south 
pole of the needle. At about the same deviation, viz., 
N. by E. i E., and at a rude altitude of about fifteen 
or twenty degrees, was an irregular cirro-cumulated 
cloud of the same purple tint, but not so much illu- 
