GEOLOGY AND MINERALGiY. 625 
Siberia is preceded by a fall of the barometer. Dr. Kane, on the 
contrary, noticed a rise before the storm above described; it stood at 
“the extraordinary height of 30°85.’ I cannot suggest any expla- 
nation of these facts. 
I believe I have now stated the true cause of what is certainly a 
very remarkable phenomenon—fluctuations of temperature of enor- 
mous magnitude, occurring in a very short time, and in the absence 
of the sun. 
SCIENTIFIC AND LITERARY NOTES. 
\ GEOLOGY AND MINERALOGY. 
UNITY OF GEOLOGICAL PHENOMENA IN THE PLANETARY SYSTEM OF THE SUN. 
BY L. SAMANN. 
M. Louis Semann, of Paris, has sent us a somewhat remarkable memoir under 
the above title, (Sur l’unité des phénoménes géologiques du systéme planetaire 
du soleil), reprinted from a recent Bulletin of the Geological Society of France. 
In this communication, after bringing forward the generally received views in 
favour of the common origin of our sun and its planetary masses, and their 
analogous chemical composition under different states of condensation, the 
author discusses in detail the peculiar condition of the moon, as apparently 
hostile to his theory. The absence of water and of an enveloping atmosphere 
(properly so-called), are of course the points thus chiefly brought under con- 
sideration. M. Semann regards the moon as having passed through various 
phases, which the earth is also in its turn eventually destined to witness. The 
smaller mass of the satellite has led to a more rapid development of these 
phases, than in the case of the larger earth mass. Both air and water he con- 
ceives to have once existed in the moon, and to have been gradually absorbed 
by the rock-matters of which this is made up; and the air and water of the 
earth, it is argued, must in the course of time be equally absorbed. In support 
of this view, the author enters into various calculations, based chiefly on the 
experiments of M. Durocher (Bulletin de la Societé Géologique, 2e sér., vol. x.) 
on the absorption of moisture by rocks generally, and he shews this to be much 
in excess of that which would arise from the complete absorption of the oceanic 
waters by the solid mass of the earth. Thus, he assumes the weight of the 
ocean to be one twenty-four thousandth part of the weight of the land; or, 
reducing all to one hundred parts, he makes the land equal to 99°9958, and the 
water to only 0:0042. On this assumption, if all the water were absorbed, the 
earth would be hydrated (so to say) to the extent of 0°000042, a mere nothing 
