354 M. F. Le Play on the Geology of [May 



But it is in the tertiary formations that the population has 

 been principally developed. The plains of the Guadiana 

 and Guadalquiver present prospects to the agriculturist 

 which are sought for in vain over the rest of the country. 

 It was on this fertile portion of the country that, under the 

 Romans and Arabs, so many populous cities grew up. 

 Here are situated Merida, with 4000 inhabitants ; Cordova, 

 which, in the days of Almanzor, extended for several 

 leagues along the banks of the Guadalquiver, but is not 

 now larger than a third-rate town in France ; and Seville, 

 whose ancient grandeur although no more, contains still 

 100,000 inhabitants. 



In this country, where nature has been so profuse with 

 her gifts, the whole land, even among the principal cities, 

 lies desolate and waste, without promising any hope for the 

 poor or security for the rich. How momentous would be 

 the change should improved institutions and morals be 

 introduced. Cultivation might be general, and, together 

 with the product of the mines, the country would support 

 a population twenty times as numerous. 



The author draws some important inferences in reference 

 to the causes of the appearances which the country of 

 Estramadura exhibits. 



1 . The inferior transition formation and crystalline rocks 

 upon which the former repose, are conformable, which 

 shews that at the period when mechanical deposition began 

 to succeed chemical eruption, no violent action occurred. 



2. The passage from the first into the second transition 

 period was marked by the appearance of the great chain of 

 Almaden. The latter, after this event, formed the crest of 

 a small island, running in the direction from east 40° north 

 to west 40° south. This island was formed at the same 

 time that Britain and the north of Normandy began to ap- 

 pear, its banks being inhabited by the same kind of mol- 

 luscous animals which existed in the latter. 



3. The termination of the second transition period was 

 marked by the elevation of the land of Estramadura, but 

 this first revolution did not raise it to the level which it at 

 present possesses. Its surface had completely emerged, 

 with the exception of some small lakes or gulfs where the 

 coal formation was afterwards deposited. 



