Projekt: Bestände der Universitätsbibliothek Freiberg
LDP: UB Freiberg Druckschriften
Strukturtyp
Band
Parlamentsperiode
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Wahlperiode
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Titel
Chap. V. Theory Of The Diminuation Of The Waters Of The Globe. - Description Of Overlying Formations. - An Investigation Of The Contents Of The Original Waters Of The Globe During The Different Periods Of The Earth's Formation. - The Division Of Rocks Into Five Great Classes
74 INTERNAL STRUCTURE. queftion has been, Whether this fluidity was the effed of Fire or Water *. Rocks which have been formed or altered by the adtion of Heat, are moll diftindly different from thofe that conftitute the great mafs of the cruft; of the globe; confequeaitly this fluidity can not be attributed to the agency of heat. Sir James Hall, a moil indefatigable chemift, hars publifhed a feries of curious experiments on the efFe&s of heat on mineral fubftances; but the refults do not apply to the prefent queftion. My colleague Profefior Playfair, in his eloquent work on the formation of minerals, has endeavoured, with the greateft addrefs, to fupport what has been denominated the Plutonic formation of the globe. But the fubftances formed by Sir James Hall in his experiments, cannot be confounded with any of thofe rocks that conftitute the cruft of the globe ; nor have the ingenuity and ability difplayed in the Illuftrations of the Huttonian Theory, re moved * It has been faid, that the figure of the Earth cannot be fatisfadlorily explained on the Neptunian fyftem, be- caufe the earth is not a folid of reyolution. This appa rently plaufible objection will vanilh, when we rcfleft, that the Neptunian fyftem only confiders the earth to have had the fpheroidal fhape when it was in a fluid form ; but that, during the formation of its folid parts, it may havo deviated more or lefs from that form, according to the inr- equality of the various depofitions.