OF SANTO DOMINGIO. 



115 



the glass, I could not determine, after many examinations, whether its whitish, granu- 

 lar appearance is due to the crj^stals of a fine-grained gi'anitoid, or to the grains of a 

 metamoi'phosed sandstone. The masses, whether beds or dykes, are so nearly verti- 

 cal that I could make out no inclination to either side in the small outcrop exposed. 

 As I have stated elsewhere, twenty-six times have I crossed this trail, and as I write, 

 I am no nearei- a satisfactory solution of the problemn than the first time I saw the 

 i'ock and knocked off a couple of specimens. • ■ 



Between the Cuesta Blanca and the main ridge, there is a broad valley watered 

 b}^ the three branches of the Arroyo Payabo, and dotted by little hills, mere. undula- 

 tions of the surface. The region is a pleasantly varied country of little park-like 

 savanas, separated by stretches of forest, through which roam wild cattle and pigs, 

 and although on the principal thoroughfare of the Republic, Avithout a human inhabi- 

 tant for twenty miles from Cevico to the one house at San Pedro on the southern 

 savana. is^othing so strongly impresses one with the sparseness of the population as 

 to see a tract like this, capable of furnishing comfortable and healthy towns to thou- 

 sands entirely unoccupied. It sounds like "vain repetition" to say that here again, 

 the white shale, usually stained red with iron and easily decomposed, showing no 

 large outcrops and no determinable dip, makes all this valley and all of the mountain 

 of the Sillon de la Yiuda. This applies, almost vv^ithout modification to the remainder 

 of the range eastward, with the little exceptions which will be noted. Almost all of 

 the streams wash out a few pebbles of sandstone and occasionally, as in the Arroyo 

 Vermejo, south of the range, near San Pedro, the shale is a little harder than 

 usual. There is no change in the character of the hills about Monte Plata and Boya 

 except a diminished height. But on the northern edge of the range, the Miocene 

 limestone of Cevico gains importance eastward ; and sometimes as beds of limestone 

 with a sufficiency though nowhei'e an abundance of characteristic fossils; sometimes 

 as a sandstone, it borders the range or caps the summits, always however horizontal. 



The best exposure of these sandstones is in the peculiar little hills of the west 

 side of San Lorenzo Bay. The same hills border all of the south side of Samana 

 Bay west of this point and form a very marked range inland. I can only describe 

 its outline as one of which all of the highest points are on a level, and which is made 

 up of a series of lumjys of pretty nearly uniform size. Closer inspection shows, that 

 these lumps are exceedingly steep hills, evidently formed by denudation, but so close to 

 each other that no level land exists between them. Where they reach the shore of 

 the bay, they usually terminate in precipitous walls, undermined by the " wash " of 

 the tide to a horizontal distance of three or four feet. This same excavating foix-c 



