After traversing a distance of twenty-seven leagues, we arrive at the river. Travellers who are inured to fatigue, always make the journey in one ride. Dr Ried accomplished the whole distance without once dismounting. The stream is called Loa, and has its source in the snows of the mountain-tops. In the neighbourhood of a small Indian village called Chiuchiu, it is fed by a little volcanic stream, which contains a large quantity of salt in a state of dissolution, besides copper, arsenic, sulphur, and other matters. The quantity of the water is increased by this supply, but its quality by no means improved; yet the abominable mixture tastes on that spot like the choicest champagne! The stream is not perceived till you stand on the very edge. Its bed is between 300 and 400 yards broad, and is about 200 or 300 feet below the average surface of the table-land. The body of water which forms this river is very inconsiderable, and becomes more and more so as it nears the sea. Here Dr Reid saw some mosquitoes, as well as a small lizard; but the presence of the quick, bright-eyed creature in that dreary waste, rather added to the sense of loneliness. Its very name, too (_Musca domestica_), seemed a mockery, dwelling as it did in that vast solitude. In the water, no trace of life was to be found. 'From the stream, which has its source in the clouds,' writes Dr Ried to his friend, 'I took a bottleful, which I send you to analyse, and in order that you may say you have seen water from Atacama. I advise you, however, not to drink it.'
In the desert, it _never_ rains. At the foot of the Cordilleras--and only at the foot--rain falls to a distance of about ten leagues westward, but _never_ further; in Atacama, to a distance of about ten leagues from the mountains; in Chili, to far beyond the coast. Perhaps, however, the most extraordinary phenomenon of this strange land, is the sudden change of temperature which takes place over the whole desert. The heat at noon is oppressive--from 96 to 120 degrees Fahrenheit; and this continues till four P.M., when it begins to diminish. From ten A.M. till about sunset, there is a strong westerly wind, blowing from the sea towards the Cordilleras. It is always fierce, but sometimes so powerful, that it is impossible to advance against it. When the sun is down, the wind likewise subsides, and till nine or ten o'clock in the evening there is a perfect calm.