i8S Movements of Jupiter's Cloud-Masses. [April, 
conditions. It was from noticing the ridges thus formed in 
ice that the writer originally took his ideas upon this class 
of geological questions. 
The writer’s own theory, which he is proud to say was 
approved by the late Mr. Scrope very shortly before his death, 
is, that there exists such a stratum in a state of igneo-aqueous 
fusion, and that it is to the steam escaping from this, and so 
diminishing its volume, that the contraction of the globe and 
the consequent compression of the crust are mainly due. 
He thinks it probable that at least a large portion of the 
water now composing the oceans has by this means been 
transferred from the under to the upper side of the solid 
crust. How thick this lubricating layer may be he does not 
undertake to say, nor how deep down. If, however, such 
does exist, there will be probably some change in the physi- 
cal relation of the substance of the earth as regards heat, at 
the surface of this stratum, such as would render the laws of 
the simple conduction of heat out of a hot solid globe towards 
the cold of space inapplicable to found upon them any 
theory as to the age of the world, or of the distribution of 
heat in its interior, based upon the observed rate of increase 
of temperature in the crust. 
III. MOVEMENTS OF JUPITER’S CLOUD- 
MASSES. 
By Richard A. Proctor. 
F Jupiter be regarded as a planet resembling our earth in 
condition, we find ourselves compelled to believe that 
processes of a most remarkable character are taking 
place on that remote world. It is singular with what com- 
placency the believers in the theory that all the planets are 
verymuch alike accept the most startling evidence respecting 
disturbances to which some among those brother worlds of 
ours must needs on that hypothesis have been subjected. 
Mighty masses of cloud, such as would suffice to enwrap 
the entire globe on which we live, form over large regions of 
Jupiter or Saturn, change rapidly in shape, and vanish, in 
the course of a few minutes ; and many are content to be- 
lieve that what has thus taken place resembles the formation, 
motion, and dissipation of our own small clouds, though the 
sun pours but about a twenty-seventh part of the heat on 
