JANUARY 11, 1884.] 
THE RED SKIES. 
THE remarkable atmospheric phenomenon 
which has recently attended sunrise and sun- 
. set, has attracted great attention not only 
from the general public, but from scientific 
men, who have endeavored to give a satisfac- 
tory explanation of it. Similar appearances 
have been noted in former years ; but they have 
been of limited extent, and attributable to local 
causes. The distinguishing characteristics of 
the present manifestation are its enormous ex- 
tent, since it has been observed over nearly the 
whole earth, its persistence, and the fact that 
the times of its first appearance have varied in 
different countries, thus suggesting a progres 
sive motion. : 
In the United States the reports of observ- 
ers of the signal-service show that its earliest 
appearance was in October. At Pensacola, 
Fla., on the 8th, the phenomenon was observed 
at both sunrise and sunset. Near the middle 
of the month it was noted along the southern 
border from southern California to the Gulf of 
Mexico. At the close of the month it was ob- 
served in great brilliancy in the southern and 
south-western states. In the more northern 
portions of the country, during October, the 
sunsets were characterized by unusual bril- 
liancy; but the peculiar ‘afterglow’ which 
marked the later appearances was not noted. 
In the early part of November the phenome- 
non was still observed on a few days in the 
south and west; but after the 20th it appeared 
in its full beauty over nearly the whole country. 
In New England, the Atlantic, Gulf, and cen- 
tral states, the lake region, the north-west, 
and along the Pacific coast, the phenomenon 
was observed, beginning at various dates after 
the 21st, according to the weather conditions 
of the different localities. The 27th was the 
date in which the appearance was first es- 
pecially marked in the eastern states. Since 
that date, to the end of the year 1883, the 
skies have been characterized by the same 
brilliancy, whenever the weather conditions 
have been favorable to its observation; the 
27th and 28th of December revealing the ap- 
pearance in the eastern section of the country 
to a marked degree. 
The sky seems to have had essentially the 
same characteristics wherever the phenomenon 
has been observed. In Europe and America, 
however, if we may judge from the published 
descriptions, the green or blue appearance of 
the sky has been less noticeable than in India, 
where the earliest observations were made. 
In this country the ‘afterglow’ has been 
SCIENCE. 
37 
ruddy, with at times an orange or greenish 
tint. The observer at Memphis, Tenn., under 
date of Oct. 30, writes, ‘‘ For more than one 
hour after sunset there was in the west a 
segment of red light, whose intensity and 
brilliancy appeared equal at all points in the 
segment. The position (altitude?) of the seg- 
ment was about 30°, azimuth 45° to 120°.”’ 
On Oct. 31 the appearance was similar, ‘‘ ex- 
cept that in the north-east quarter of the seg- 
ment a few converging bands, apparently dark, 
entered the segment from a clear sky. While 
no stars were visible in the illumined part of 
the segment, they were visible in all other 
parts of the sky, and also in the bands, which, 
it appears, were dark in contrast.’’ At Wash- 
ington, on Dec. 29, a ruddy arch arose in the 
early morning, and was about 25° high an 
hour and ten minutes before sunrise. Soon 
after, the usual twilight arch appeared, also of 
a ruddy tint; and the two were seen simul- 
taneously, the former losing its outline, and 
growing paler as it became tranfused over the 
sky. During the day, the material causing 
the appearance was plainly visible as a white 
haze surrounding the sun to a distance of 
about 30°. At sunset on the 27th and 28th 
the phenomena were as at sunrise, but in re- 
verse order, the secondary glow lasting an 
hour and three-quarters after sunset. While 
the glow at the end of December is perhaps 
not as intense in color as when first seen a 
month earlier, it is the same in other respects. 
It has been described in profuse detail in the 
daily press; and several English magazines, 
notably Nature, have devoted much space to 
it. 
Three different hypotheses have been advo- 
cated to explain the phenomenon, assigning 
its cause to aqueous vapor, meteoric and vol- 
canic matter respectively. It is undoubtedly 
atmospheric, and due to the, presence of some 
matter in unusual quantities. The persistence 
of the phenomenon, and its great extent, are 
objections to the view that it is due to aqueous 
vapor. There would certainly have been, ere 
this, extensive precipitation, were aqueous va- 
por the cause; but reports indicate nothing 
abnormal in the rainfall. Moreover, the glow 
has been most noticeable when the air has been 
driest: it has been a characteristic of the cold, 
dry weather, which attends areas of high baro- 
metric pressure. In addition, the spectroscope 
has confirmed the indications of the psychrom- 
eter.. The pocket-spectroscope shows a very 
weak rain-band, and a strong development of 
the bands designated by Piazzi Smyth as a 
and 6, and ascribed by him to ‘ dry air,’ the 
