and Orography of the EartKs Surface. 9 



geological maps, others for each period of time ; and in the 

 last will be indicated not only the place of the various for- 

 mations, but also the values of the various elevations and 

 subsidences. These values will consist in the indications of 

 the height, extent, and breadth, of the chains, of the angle of 

 inclination of those as well as of the beds of rivers, the depth 

 of the seas, the temperature of the different periods, the mag- 

 netic phenomena during these periods, and, last, the general 

 geography of the different fossil flora and fauna. 



A beginning is made in this way with the Palaiohydro- 

 graphy and Orography, but the palaeophysics are hardly 

 studied, and even less the palseoehemistry. We have got 

 very few notions on palseometeorology and palseotemperature 

 or thermics, as for instance in the changes in the isothermal 

 lines in the geological times (Bui. Soc. Geol., 1848, vol. v. 

 p. 276). The palseomagnetism, connected intimately with 

 temperature changes, will also give rise to most interesting 

 discoveries, and even to magnetical maps in the various 

 geological periods. Upon palseohydrology, I may soon treat, 

 and upon palseopotanography I have selected a few facts 

 already (Mem. of the Vienna Acad., 1851, vol. iii. p. 89). In 

 a later paper I have shewn, by the various degrees of heat 

 in the thermal waters, where many different vegetables and 

 animals of higher and lower classes may have lived, and 

 that the temperature of the sea, at the beginning, could not 

 have been so great as philosophers thought. The maximum 

 of that temperature could have varied only between 70° and 

 80° C. ; but in the general one I found only about 30° or 40°, 

 like Sir H. de la Beche (Bui. Soc. Geol. for 1852, vol. ix.) 

 The last knowledge mankind will acquire is that of Palceo- 

 astronomy ; but a proper knowledge of this branch will require 

 many centuries of time. 



