PBEPAEATIONS FOB TILE DESCENT. 
437 
quartz.* It may be conceived that the valley of Caracas 
was once an inland lake, before the Itio Guayra found an 
issue to the east near Caurimarc, at the foot of the hill 
of Auyamas, and before the ravine of Tipe opened on the 
west, in the direction of Gatia and Cabo Blanco. But how 
can we imagine that these waters could ascend as high as 
the Silla, when the mountains opposite this peak, those of 
Ocumare, were too low to prevent their overflow into the 
llanos? The pebbles could not have been brought by 
torrents from more elevated points, since there is no height 
that commands the Silla. Must we admit that they have 
been heaved up, like all the mountains which border the 
coast. 
It was half after four in the afternoon when we finished 
our observations. Satisfied with the success of our journey, 
we forgot that there might be danger in descending in tire 
dark, steep declivities covered by a smooth and slippery turf. 
The mist concealed the valley from us ; but we distinguished 
the double hill of La Pucrta, which, like all objects lying 
almost perpendicularly beneath the eye, appeared extremely 
near. We relinquished our design of passing the night 
between the two summits of the Silla, and having again 
found the path we had cut through the thick wood of 
heliconia, we soon arrived at the Pcjual, the region of 
odoriferous and resinous plants. The beauty of the befarias, 
and their branches covered with large purple flowers, again 
rivetted our attention. When, in these climates, a botanist 
gathers plants to form his herbal, he becomes difficult in 
his choice in proportion to the luxuriance of vegetation. He 
casts away those which have been first cut, because they 
appear less beautiful than those which were out of reach. 
Though loaded with plants before quitting the Pejual, we 
still regretted not having made a more ample harvest. We 
tarried so long in this spot, that night surprised us as we 
entered the savannah, at the elevation of upwards of nine 
hundred toises. 
As there is scarcely any twilight in the tropics, we pass 
suddenly from bright daylight to darkness. The moon was 
on the horizon ; but her disk was veiled from time to time 
* Fragments of brown copper- ore were found mixed with these pebbles, 
an elevation of J!70 toises. 
