Geology and Natural History. 145 
II. GeoLtogy anp Naturat History. 
. Voleanie Energy: an attempt to develop its true Origin and 
Cosmical Relations ; by Roserr Matuet, A.M. F.R.S, ete 
This important paper is now published in full in the Journal of the 
Royal Society, having been read in abstract June 20, 1872. 
e author accepts in general Sir W. Thomson’s view, that plu- 
tonic action or “ Vuleanicity ” results from the dissipation of 
develops the idea first distinctly expressed by Constant Prevost, 
that elevation, folding and crushing of strata is the result of tan- 
gential pressure, originating in the contraction of the earth’s crust 
by secular refrigeration; considering the latter, as well as t e gen- 
eral increase of temperature, with depth, as facts sufficiently 
established, 
ming that in consequence of the viscosity of the cooling 
materials, the temperature would, after a certain epoch, always have 
een highest near the center of the mass ; and that a crust began 
d began to corrugate and double upon itself, elevating moun 
i now fo 
an 
chains along the lines of weakness, and extruding rocks, now form- 
h period, of a 
efined: 
present 
be, by 
rushing 
