. II. RELICS, into Min. Kibgd. 19 



A. 8 The periods of introduction may be reduced 

 to three principal and determinate ones 



added a few cursory observations and notices, illustrative of the 

 geological opinions of De Luc, Hutton, c. 



FORMATION OF THE EARTH, 



AND 



Introduction of Extraneous Fossils into the Mineral Kingdom, 



According to the modern Neptunian System. 



1 . The materials which compose the globe, or at least its super- 

 ficial parts to a certain depth, have been in a soft or fluid state. 



(Obs. De Luc supposes our globe, during the first periods of its 

 existence, to have consisted of a dry, central mass, with another 

 concentrical to this, in a soft or mud-like state, and a liquid covering 

 the whole, and containing the various substances, which after- 

 wards formed by precipitation the primordial strata.) 



2. This fluidity was the effect of solution in water, and not of 

 igneous fusion. 



3. The different earths, together with the saline, inflamtiiable, 

 and metallic substances, thus dissolved or suspended in water, con- 

 stituted what has been called the chaotic fluid. 



(Obs. Mr. Kirwan believes, that the various mineral substances, 

 which the surface of the globe at present exhibits, were at the very 

 commencement of their existence, in that state of minute division, 

 aqueous solution requires ; and, of course, not orginally created in 

 a solid or compact form, and afterwards dissolved, as some authors, 

 who support the Neptunian theory, have supposed. Vide Geol. 

 Essays, p. 10.) 



4. From this fluid, the substances just specified were successively 

 and, at distant periods, gradually deposited. 



5. These depositions were either chemical or mechanical. 



(Ob. Stones originating from mechanical deposits are distin- 

 guished by the want of the sparry or crystalline texture ; or, more 

 generally, by their integrant parts exhibiting traces of fracture and 

 attrition ; as in some sandstones, pudding-stones, certain limestones, 

 &c. In chemical deposits there is no such appearance, the con- 



