254 



NATIVE ALUM. 



untrue a report of their death on the Orinoco, which 

 had been current for several months. The port wa3 

 every day more strictly blockaded, and the vain ex- 

 pectation of Spanish packets retained them two 

 months and a half longer ; during which time they 

 occupied themselves in completing their investiga- 

 tion of the plants of the country, in examining the 

 geology of the eastern part of the peninsula of Araya, 

 and in making astronomical observations, together 

 with experiments on refraction, evaporation, and at- 

 mospheric electricity. They also sent off some of 

 their more valuable collections to France. 



Having been informed that the Indians brought to 

 the town considerable quantities of native alum found 

 in the mountains, they made an excursion for the 

 purpose of ascertaining its position. Disembarking 

 near Cape Caney they inspected the old salt-pit, now 

 converted into a lake by an irruption of the sea, the 

 ruins of the castle of Araya, and the limestone- 

 mountain of Barigon, which contained fossil shells 

 in perfect preservation. When they visited that 

 peninsula the preceding year, there was a dreadful 

 scarcity of water. But during their absence on the 

 Orinoco it had rained abundantly on various parts 

 along the coast; and the remembrance of these 

 showers occupied the imagination of the natives as 

 a fall of meteoric stones would engage that of the 

 naturalists of Europe. 



Their Indian guide was ignorant of the situation 

 of the alum, and they wandered for eight or nine 

 hours among the rocks, which consisted of mica- 

 slate passing into clay-slate, traversed by veins of 

 quartz, and containing small beds of graphite. At 

 length, descending towards the northern coast of 

 the peninsula, they found the substance for which 

 they were searching, in a ravine of very difficult ac- 

 cess. Here the mica-slate suddenly changed into 

 carburetted and shining clay-slate, and the springs 

 were impregnated with yellow oxide of iron. The 



