1874.] The Saturnian System. 25 
place in the real globe of Saturn, or even that his atmo- 
sphere becomes at times heaped up in particular regions; 
but there is nothing to prevent the occasional existence 
(perhaps for long periods of time) of cloud-layers at higher 
levels than usual in the temperate zones, or else the occa- 
sional dissipation of the higher cloud-layers in the equatorial 
zone. 
I have described, in my ‘‘ Other Worlds,” an observation 
of the ingress of one of Jupiter’s satellites on the disc, and 
its subsequent reappearance, as though tt had retraced tts course ; 
and I have shown that the only conceivable explanation of 
this remarkable phenomenon (witnessed by three excellent 
observers at different stations) appears to reside in the rapid 
dissipation of a high cloud-layer. I have never seen any 
other explanation even suggested; and, for my own part, I 
cannot agree with those who would simply abandon all 
attempt at explanation. 
The general conclusion to which all the evidence, as it 
seems to me, would appear to point, is that both Jupiter 
and Saturn are in a semi-sun-like condition. It is not alto- 
gether correct to say that they occupy a position midway 
between that of the earth and that of the sun, for, in point 
of fact, such a mode of expression does not*admit of any 
definite interpretation. It is manifest, moreover, that in 
some respects Jupiter and Saturn are utterly unlike the sun, 
while in other respects they are utterly unlike the earth and 
her fellow terrestrial planets. ‘They must be regarded as 
sui generis; and it must be the work of long and careful 
observation with the best telescopes to ascertain the nature 
of these orbs. This is a subject of independent research, 
and although some analogies suggested by our knowledge of 
the earth, and other analogies suggested by our knowledge 
of solar phenomena, may be useful as guides, yet, on the 
whole, the safest course will be to pursue the inquiry in an 
independent manner. And here I would note that there is 
excellent promise of new information to be derived from the 
systematic observation of Saturn and Jupiter in both hemi- 
spheres of the earth.* Hitherto most of the observations 
* It would not, indeed, be necessary that northern and southern observatories 
should be engaged in the work if an observatory could be established, for 
researches into the physics of astronomy, in some elevated region of our pos- 
sessions in British India. For, near the equator, the ecliptic at all times 
passes high above the horizon. It was proposed some time since, by 
an almost unanimous vote of the council of the Astronomical Society, that 
such an observatory should be erected for the purpose indicated. Whether 
this proposal will be carried out remains to be seen. It unfortunately was 
made only as arr amendment on a proposition of an eminently unsatisfactory 
VOL. IV. (N.S.) E 
