a Theory <>f the Earth. $$ 



CHAP. I. 



Ajlronomical Principles. 

 i. A general fyftem of cofmology, in what regards the 

 earth confidercd as a planet. 



2. The figure and dimenfions of the earth determined. 



3. The denfity of the earth determined by the deviation 

 of a plummet near fome mountains, the dimenfions and 

 denfity of which are known. 



4. Whether any principles or hypothefes, depending 011 

 aftronomical geography, can explain the great changes in 

 the temperature of fome parts of our o-lobe ? 



5. The courfes of comets. Whether it be poffible that 

 they may have met with, or ftill meet with, the earth 

 in their orbits, and what are the effects of fuch a meeting ? 



6. Whether it be poffible, I do not fay probable, that a 

 comet, by paffing through part of the fun, may have detached 

 from it the earth and the other planets ? 



7. Is it probable that the earth's rotary motion has been 

 formerly more rapid than it is at prefent ? 



8. If the grand chains of mountains exifted before the 

 rotary motion of the earth, is it poffible that that motion 

 produced any change in their original fituation * ? 



CHAP. 11. 

 Chemical and Vhyjical Principles. 



1. The theory of attraction and chemical affinities; of 

 folution, cryftallifation, and precipitation. 



2. The theory of elaftic fluids in general, and the caufe 

 of their elafticity f. 



3. The theory of caloric and light; of the origin and 

 nature of the different gafes, and of the atmofphere. Elec- 

 tricity, and the aurora borealis. 



* Tableau dts Etats Unis. Note of M. A. Pictct, p. 125. 

 t Syflcm of M. Le Sage. 



D 2 4. The 



