XV 
SWARM OF LOCUSTS 
35i 
outer range of the Cordillera, we did not cross a single stream. 
In many parts the ground was incrusted with a saline efflor¬ 
escence ; hence we had the same salt-loving plants which are 
common near Bahia Blanca. The landscape has a uniform 
character from the Strait of Magellan, along the whole eastern 
coast of Patagonia, to the Rio Colorado ; and it appears that 
the same kind of country extends inland from this river, in a 
sweeping line as far as San Luis, and perhaps even farther 
north. To the eastward of this curved line lies the basin of 
the comparatively damp and green plains of Buenos Ayres. 
The sterile plains of Mendoza and Patagonia consist of a bed 
of shingle, worn smooth and accumulated by the waves of the 
sea ; while the Pampas, covered by thistles, clover, and grass, 
have been formed by the ancient estuary mud of the Plata. 
After our two days’ tedious journey, it was refreshing to see 
in the distance the rows of poplars and willows growing round 
the village and river of Luxan. Shortly before we arrived at 
this place we observed to the south a ragged cloud of a dark 
reddish-brown colour. At first we thought that it was smoke 
from some great fire on the plains ; but we soon found that it 
was a swarm of locusts. They were flying northward ; and with 
the aid of a light breeze, they overtook us at a rate of ten or 
fifteen miles an hour. The main body filled the air from a 
height of twenty feet to that, as it appeared, of two or three 
thousand above the ground ; “ and the sound of their wings was 
as the sound of chariots of many horses running to battle or 
rather, I should say, like a strong breeze passing through the 
rigging of a ship. The sky, seen through the advanced guard, 
appeared like a mezzotinto engraving, but the main body was 
impervious to sight ; they were not, however, so thick together, 
but that they could escape a stick waved backwards and for¬ 
wards. When they alighted, they were more numerous than 
the leaves in the field, and the surface became reddish instead of 
being green : the swarm having once alighted, the individuals 
flew from side to side in all directions. Locusts are not an 
uncommon pest in this country : already during this season 
several smaller swarms had come up from the south, where, as 
apparently in all other parts of the world, they are bred in the 
deserts. The poor cottagers in vain attempted, by lighting fires, 
by shouts, and by waving branches, to avert the attack. This 
