94 



PORTO RICO 



Although it nowhere attains the great altitudes of the other 

 Antilles, the island is practically the eastward continuation of 

 the Antillean chain of uplifts. It rises from the shallow sub- 

 merged bank which borders it for a few miles and is a contin- 

 uation of the other Antilles. This bank is the upward extension of 

 a remarkable submerged mountain slope, which, at least on the 

 north side, descends nearly 30,000 feet to the bottom of the Brown- 

 son Deep, until recently supposed to be the deepest hole in the 

 world. 



Its outline presents the appearance of an almost geometrically 

 regular parallelogram nearly three times as long as broad, with 

 its four sides following the four cardinal directions. The sea- 

 line, unlike that of Cuba, is almost straight, and the coast is 

 usually low, especially on the southern side, although there are 

 a few headlands. It is also void of fringing keys and deep indenta- 

 tions of its coast, such as border the island of Cuba. 



Porto Rico, like all the Antilles, in comparison with the United 

 States, has a configuration ancient in aspect, although compara- 

 tively new in geologic age, the material all being of late Cretaceous 

 and younger periods. Of the four chief topographic features of 

 the Great Antilles — central mountains, coast-border topography, 

 interior plains, and inclosed mountain basins — only the central 

 mountains and coast-border topography are represented upon 

 this island. 



The central mountains, which are the largest conspicuous east- 

 ern member of the partiahy submerged chain of the Great Antilles 



COFFEE ESTATE IX MAYAGUEZ DISTRICT 



