.835. SWARM OF LOCUSTS. 329 



character from the Strait of JMagellan, along the whole eastern 

 coast of Patagonia, to the Rio Colorado ; and it appears that tlie 

 same kind of country extends inland from this river, in a sweep- 

 ing line as far as San Luis, and perhaps even further north. To 

 the eastward of this curved line, lies the basin of the compara- 

 tively 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 darii 

 reddish-brown colour. At first we thought tliat 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- 

 v/ards. When they alighted, they were more numerous than tlie 

 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 un- 

 common 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 species 

 of locust closely resembles, and perhaps is identical with the 

 famous Grvllus migratorius of the East. 



We crossed the Luxan, which is a river of considerable size, 



