Di- Boue's Geological Observations. ® 



effects must also have been produced formerly as now ; but their 

 causes being then infinitely greater than at present, the changes 

 operated must also have been proportionally much more consider- 

 able. This, also, seems to explain to us the rising up of certain 

 strata, or certain parts of continents, as well as the successive sink- 

 ing of the level of the sea, or its inclosure within its present limits. 

 It is obvious that a consequence resulting from this is, that, in 

 the earlier states of the globe, the seas and continents were chan- 

 ging more rapidly than in the more modern ; that the tempera- 

 ture of the earth also was decreasing more rapidly : but, at the 

 same time, in consequence of this decreasing heat, the evapora- 

 tion must have diminished ; the rays of the sun, in a less moist 

 atmosphere, must have become less hot ; the rains must have 

 decreased in quantity, and the atmospheric meteors must have 

 generally become less considerable ; the streams of water must 

 have gradually lost their original greatness, as well as their de- 

 structive energy; and the inclined planes along which they 

 flowed must have diminished, or increased, according to local 

 circumstances. On the other hand, the countries from which 

 the sea was retiring, or those which had been raised up, must 

 have lost a part of their temperature. It is also to be conclud- 

 ed, that the diminution of the temperature was not equally the 

 same over the whole surface of the globe, but that it took place 

 in proportion to the extent of the volcanic masses, to the degree 

 of their cooling, to that of the retreat of the sea, and to the po- 

 sition of the different parts of the earth, compared with their 

 level above the sea, with their removal from the sea. and with 

 their position in reference to the sun. The last propositions 

 shew, first, the probability that there have always been parts on 

 the earth warmer than the others; and explain, besides, how the 

 zones of temperature have been established in latitude, longi- 

 tude and height, and also, according to local circumstances, the 

 various climates of the whole earth. It is known that every 

 zone, and nearly every climate that is more or less general, has 

 its pecuhar animals and vegetables ; or, at least, it is a fact, that 

 the distribution of animals and vegetables is most materially in- 

 fluenced by the division of the surface of the earth into zones, 

 and into countries or climates. Is it not fiatural to search in the 

 successive establishment of these different zones and climates. 



