NATIVE ALUM. 995 
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. Disembark- 
ing 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 lime- 
stone-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, de- 
scending toward the northern coast of the peninsula, 
they found the substance for which they were search- 
ing, in a ravine of very difficult access. Here the mica- 
slate suddenly changed into carburetted and shining 
clay-slate, and the springs were impregnated with 
yellow oxide of iron. The sides of the neighbouring 
cliffs were covered with capillary crystals of sulphate 
of alumina, and real beds, two inches thick, of native 
alum, extended in the clay-slate as far as the eye 
could reach. The formation appeared to be primi- 
tive, as it contained cyanite, rutile, and garnets. 
