434 FIRST VIEW OP THE PACIFIC. 



of Bougainvillaea. This valley is one of the deepest with which I 

 am acquainted in the chain of the Andes : it is a true tranverse 

 valley directed from east to west, deeply cleft, and hemmed in on the 

 two sides by the Altos de Aroma and Guangamarca. In this val- 

 ley recommences the same quartz formation which we had observed 

 in the Paramo de Yanaguanga, between Micuipampa and Caxamarca, 

 at an elevation of 11,720 English feet, and which, on the western 

 declivity of the Cordillera, attains a thickness of several thousand 

 feet, and was long an enigma to me. Since von Buch has shown us 

 that the cretaceous group is also widely extended in the highest 

 chains of the Andes, on either side of .the Isthmus of Panama, the 

 quartz formation which we are now considering, which has perhaps 

 been altered in its texture by the action of volcanic forces, may be 

 considered to belong to the Quadersandstein, intermediate between the 

 upper part of the chalk series and the Gault and Greensand. -On 

 quitting the mild temperature of the Magdalena Valley, we had to 

 ascend again for three hours the mountain wall of 5120 English 

 feet, opposite to the porphyritic group of the Alto de Aroma. The. 

 change of climate in so doing was the more sensible, as we were often 

 enveloped, in the course of the ascent, in. a cold fog. 



The longing desire which we felt. to enjoy once more the open 

 view of the sea, after eighteen months' constant sojourn in the ever- 

 restricted range of the interior of the mountains, had been height- 

 ened by repeated disappointments. In looking from the summit 

 of the volcano of Pichincha, over the dense forests of the Provincia 

 de las Esmeraldas, no sea horizon can be clearly distinguished, by 

 reason of the too great distance of the coast and height of the 

 station : it is like looking down from an air-balloon into vacancy. 

 One divines, but one does not distinguish. Subsequently, when 

 between Loxa and Guancabamba we reached the Paramo de Gua- 

 mini, where there are several ruined buildings of the times of the 

 Incas, and from whence the mule-drivers had confidently assured us 

 that we should see beyond the plain, beyond the low districts of 

 Piura and Lambajeque, the sea itself which we so much desired to 

 behold, a thick mist covered both the plain and the distant sea- 

 shore. We saw only variously shaped masses of rock alternately 



