298 M. Ami Boue on the Palozohydrography 



now twenty species of Lepidosteus from the United States in 

 my collection, a good foundation upon which to base a revi- 

 sion of the fossil fishes. I could not say how many other 

 new things I have collected, for I have not yet unpacked 

 half my packages. — (A merican Journal of Science and Arts, 

 vol. xvi., No. 46.) 



On the Palceohydrography and Orography of the Earth's 

 Surface, or the probable position of Waters and Continents, 

 as well as the probable Depths of Seas, and the absolute 

 Heights of the Continents and their Mountain-Chains du- 

 ring the different geological periods. By M. Ami Boue'. 

 Communicated by the Author. 



The Palseohydrography is an old principle in geology, and 

 is even still considered so by geographers and theoretical 

 geologists who have not a correct knowledge of all the facts 

 upon which this doctrine is founded. Water having covered 

 the surface of the earth from the time that temperature per- 

 mitted it, its abrading effects must have been in action during 

 all periods of time. During each of these periods there were 

 sea-shores, sea-cliffs, river-beds, and the like. Many of the 

 sea water-marks have, in all probability, been destroyed by 

 the length of these various operations, but here and there 

 some still exist ; and it now remains for the expert geologist 

 to arrive at the date of the origin of each of these. We will 

 then be able to draw general geognetic conclusions from such 

 a mass of well-established facts. We have an able essay on 

 this interesting subject by Mr Robert Chambers (yid. Ancient 

 Sea-Margins, 1848). It is necessary to proceed in this in- 

 quiry from the most recent phenomena to the oldest, as I 

 have already shewn in a memoir on the subject {Proceedings 

 of the Vienna Academy, J anuary 1850). From the water- 

 marks of a fresh-water lake that is now empty, we come to 

 those of interior seas, of Mediterraneans, and last of Oceans. 

 From these, we proceed to the water-marks of Tertiary and 

 Secondary seas, and combine these facts with those given by 

 the theory of elevation and subsidence of the earth's surface. 

 Palaeontology is highly useful in this inquiry, for instance, 



