182 S. CRUZ, PATAGONIA. [cHap. Ix. 
-ments, and these lying scattered on the beach, were reduced first 
‘to smaller blocks, then to pebbles, and lastly to the most impal- 
pable mud, which the tides drifted far into the Eastern or 
Western Ocean. , : 
With the change in the geological structure of the plains the 
character of the landscape likewise altered. While rambling 
up some of the narrow and rocky defiles, I could almost have 
fancied myself transported back again to the barren valleys or 
the island of St. Jago. Among the basaltic cliffs, I found some 
plants which I had seen nowhere else, but others I recognised as 
being wanderers from Tierra del Fuego. These porous rocks 
serve as a reservoir for the scanty rain-water; and consequently 
on the line where the igneous and sedimentary formations unite, 
some small springs (most rare occurrences in Patagonia) burst 
forth ; and they could be distinguished at a distance by the cir- 
cumscribed patches of bright green herbage. 
April 27th.—The bed of the river became rather narrower, 
and hence the stream more rapid. It here ran at the rate of six 
knots an hour. From this cause, and from the many great 
angular fragments, tracking the boats became both dangerous 
and laborious. 
This day I shot a condor. It measured from tip to tip of the 
wings, eight and a half feet, and from beak to tail, four feet. 
This bird is known to have a wide geographical range, being 
found on the west coast of South America, from the Strait of 
Magellan along the Cordillera as far as eight degrees N. of the 
equator. The steep cliff near the mouth of the Rio Negro is its 
northern limit on the Patagonian coast; and they have there 
wandered about four hundred miles from the great central line 
of their habitation in the Andes. Further south, among the 
bold precipices at the head of Port Desire, the condor is not 
uncommon; yet only a few stragglers occasionally visit the sea- 
coast. A line of cliff near the mouth of the Santa Cruz is fre- 
quented by these birds, and about eighty miles up the river, 
where the sides of the valley are formed by steep basaltic pre- 
cipices, the condor reappears. From these facts, it seems that 
the condors require perpendicular cliffs. In Chile, they haunt, 
during the greater part of the year, the lower country near the 
