Narrative of the surveying voyages of His Majesty's Ships Adventure and Beagle, Vol. 3 [of 3] · Charles Darwin
NORTHERN CHILE AND PERU.
We staid two days at Freyrina. In the valley of Guasco there are four small towns. At the mouth, there is the port, a spot entirely desert, and without any water in the immediate neighbourhood. Five leagues higher up stands Freyrina, a long straggling village, with decent whitewashed houses. Again, ten leagues further up, Ballenar is situated, and above this Guasco Alto, a horticultural village, famous for its dried fruit. On a clear day, the view up the valley is very fine; the straight opening is terminated at a great distance by the outline of the snowy Cordillera; on each side an infinity of crossing lines blend together in a beautiful haze. The foreground is singular, from the number of parallel and extensive terraces; and the included strip of green valleys with its willow bushes, is contrasted on both hands by the naked hills. That the surrounding country was most barren, will be readily believed, from the circumstance of a shower of rain not having fallen during the last thirteen months. The inhabitants heard with the greatest envy of the rain in Coquimbo; from the appearance of the atmosphere they had strong expectations of equally good fortune, which, a fortnight afterwards, was realized. I was at Copiapó at the time; and there the people, with equal envy, talked of the abundant rain at Guasco. After two or three very dry years, perhaps with not more than one shower during the whole time, a rainy year generally follows; and this does more harm than even the drought. The river swells, and covers with gravel and sand the narrow strip of ground, which alone is fit for cultivation. The flood also injures the irrigating ditches. Great devastation had thus been caused three years ago.
JUNE 8TH.--We rode on to Ballenar. As the rocky mountains on each hand were concealed by clouds, the terrace-like plains gave the valley an appearance similar to that of Santa Cruz, in Patagonia. I staid the following day in the town, which is as large as Coquimbo and well built. It has only lately sprung up, and entirely owes its prosperity to some silver-mines. Ballenar takes its name from Ballenagh, in Ireland, the birthplace of the family of O’Higgins, who, under the Spanish government, were presidents and generals in Chile. 10TH.--Instead of going direct to the town of Copiapó, I determined to fall into the valley higher up and nearer the Cordillera. We rode all day over an uninteresting country; I am tired of repeating the epithets barren and sterile. These words, however, as commonly used, are comparative: I have always applied them to the plains of Patagonia; yet the vegetation there can boast of spiny bushes and some tufts of grass, which is absolute fertility to any thing that can be seen here. And here again there are not many spaces of two hundred yards square, where some little bush, cactus or lichen, may not be discovered by careful examination; and in the soil seeds lie dormant ready to spring up during the first rainy winter. In Peru real deserts occur, over wide tracts of country. In the evening we arrived at a valley, in which the bed of the streamlet was damp: following it up, we came to tolerably good water. During the night, the stream, before it is evaporated and absorbed, flows a league lower down than during the day. Sticks were plentiful for firewood, so that it was a good place of bivouac for us: but for the poor animals there was not a mouthful for them to eat.
JUNE 11TH.--We rode without stopping for twelve hours, till we reached an old smelting furnace, where there was water and firewood; but our horses again had nothing to eat, being shut up in an old courtyard. The line of road was hilly, and the distant views interesting from the splendid weather, and the varied colours of the bare mountains. It is a pity to see the sun shining constantly over so useless a country; such days should brighten a prospect of fields and gardens. The next day we reached the valley of Copiapó. I was heartily glad of it; for the whole journey was a continued source of anxiety; it was most disagreeable to hear, whilst eating our own supper, our horses gnawing the posts to which they were tied, and to have no means of relieving their hunger. To all appearance, however, the animals were quite fresh; and no one could have told that they had eaten nothing for the last fifty-five hours.
I had a letter of introduction to Mr. Bingley, who received me very kindly at the Hacienda of Potrero Seco. This estate is between twenty and thirty miles long; but it is very narrow, having generally a width of only two fields, one on each side the river. In some parts, the estate is of no width, that is to say, the land cannot be irrigated, and therefore is valueless, like the surrounding rocky desert. The small quantity of cultivated land in the whole line of valley, does not however so much depend on its inequality, or its unfitness for irrigation, as on the small supply of water. The river this year was remarkably full; in this part it reached as high as the horse’s belly, and was about fifteen yards wide, and rapid. It gradually decreases in volume till reaching the sea. This latter circumstance, however, rarely happens; and once for a period of thirty years not a drop entered the Pacific. The inhabitants watch a storm over the Cordillera with great interest: as one good fall of snow provides them with water for the ensuing year. This is of infinitely more consequence than rain in the lower country.
The latter, as often as it occurs, which is about once in every two or three years, is a great advantage, because the cattle and mules can for some time afterwards find pasture in the mountains. But without snow in the Andes, desolation extends throughout the valley. It is on record, that three times nearly all the inhabitants have been obliged to emigrate to the south. This year there was plenty of water, and every man irrigated his ground as much as he chose; but it has frequently been necessary to post soldiers at the sluices, to see that each estate took only its proper allowance during so many hours in the week. The valley is said to contain 12,000 souls, but its produce is sufficient only for three months in the year; the rest of the supply being drawn from Valparaiso and the south. Before the discovery of the famous silver-mines of Chanuncillo, Copiapó was in a rapid state of decay; but now it is in a very thriving condition; and the town, which was completely overthrown by an earthquake, has been rebuilt. The valley of Copiapó, forming a mere ribbon of green in a desert, runs in a very southerly direction; so that it is of considerable length to its origin in the Cordillera. The valleys of Guasco and Copiapó may both be considered as islands to the northward of Chile, separated by deserts instead of salt water. Beyond these, there is one other very miserable valley, called Paposo, which contains about 200 people; and then there extends the real desert of Atacama--a barrier far worse than the most turbulent ocean.
After staying a few days at Potrero Seco, I proceeded up the valley to the house of Don Benito Cruz, to whom I had a letter of introduction. I found him most hospitable; indeed it is impossible to bear too strong testimony to the kindness which travellers receive in almost every part of South America. The next day I hired some mules to take me by the ravine of Jolquera into the central Cordillera. On the second night the weather seemed to foretel a storm of snow or rain, and whilst lying in our beds we felt a trifling shock of an earthquake. The connexion between the latter phenomena and the weather has often been a disputed point: it appears to me to be one of very great interest, and not well understood. Humboldt[1] has remarked, “It would be difficult for a person, who has lived a long time in New Andalusia, or in the low regions of Peru, to deny that the season, the most to be dreaded from the frequency of earthquakes, is that of the beginning of the rains, which is, however, the time of thunderstorms. The atmosphere, and the state of the surface of the globe, seem to have an influence unknown to us, on the changes produced at great depths.” In Northern Chile, from the extreme infrequency of rain, or even of weather foreboding rain, the probability of accidental coincidences between the two phenomena necessarily becomes very small; yet the inhabitants in that part are most firmly convinced of some connexion between the state of the atmosphere and the tremblings of the ground. I was much struck by this, when mentioning to some people at Copiapó that there had been a sharp shock at Coquimbo: they immediately cried, “How fortunate! there will be plenty of pasture there this year.” To their minds an earthquake foretold rain, as surely, as rain foretold abundant pasture. Certainly it did so happen that on the very day of the earthquake, that shower of rain fell, which I have described as in ten days producing a thin sprinkling of grass.
Mr. Scrope has put forth an ingenious idea, that the period of subterranean disturbance, where the force is just on a balance with the resistance, may be determined by a sudden decrease in atmospheric pressure, which over a wide extent of country might produce a considerable effect. According to this explanation, the earthquake comes on at the given period from that state of the weather, which is generally accompanied by rain. But there is another class of phenomena, where the state of the weather evidently appears a consequence (and not the determining cause) of the earthquake. I allude to those cases, when rain falls at a period of the year, at which it is a greater prodigy than the earthquake itself: I may instance the rain after the shock of November, 1822, at Valparaiso. A person must be somewhat habituated to these climates, to understand the excessive improbability of rain falling at such seasons, except as a consequence of some law quite unconnected with the ordinary course of the weather. In the case of great volcanic eruptions, as that of Coseguina, where torrents of rain fell at a time of year most unusual for it, and “almost unprecedented in Central America,”[2] it is not difficult to understand that the volumes of vapour and clouds of ashes, might have disturbed the atmospheric equilibrium. Humboldt[3] extends this view to the case of earthquakes; but for my part, I cannot conceive it possible, that the small quantity of aeriform fluid which at such times escapes from the fissured ground, can produce such remarkable effects.
Humboldt[4] has stated that, “on the days when the earth is shaken by violent shocks, the regularity of the horary variations of the barometer is not disturbed under the tropics. I have verified this observation at Cumana, at Lima, and at Riobamba; and it is so much the more worthy of fixing the attention of natural philosophers, as at St. Domingo, at the town of Cape François, it is asserted, that a water barometer[5] was observed to sink two inches and a half immediately before the earthquake of 1770. In the same manner it is related, that, at the destruction of Oran, a druggist fled with his family, because observing accidentally a few minutes before the earthquake, the height of the mercury in his barometer, he perceived that the column sunk in an extraordinary manner. I know not whether we can give credit to this assertion.” Mr. Alison, in a letter dated Valparaiso, informs me, that just before the earthquake of November, 1822, the mercury in the tube of the barometer standing in his store, sank beneath the graduated part. The tube was a bent one; nineteen inches being exposed, and the lowest graduated part corresponded to twenty-six English inches. With this third case, and more especially considering the unquestionable fact of rain so frequently following severe earthquakes, even at the most unusual seasons, I cannot conclude otherwise, than that there exists some connexion between the subterranean and atmospheric disturbances, of which we are at present quite ignorant.
Mr. Miers,[6] in his account of the Valparaiso earthquake, November 19th, 1822, has added one more to the list of coincidences between luminous meteors and earthquakes. He says “one of very considerable size, in apparent dimensions little less than the moon, was observed in the southward, at no very great elevation. It traversed a considerable arch of the heavens, leaving behind it a long train of light; and when it disappeared, it seemed to do so from explosion--as it leaped in the same manner as those which eject meteoric stones; but in this instance no noise was heard to attend its extinction, nor was it known that any stones fell. This occurred about half-past two o’clock in the morning after the earthquake.” The earthquake itself happened at half-past ten o’clock. Mr. Miers then adds, that a friend of his “travelling on the night of the 4th of November, about a fortnight preceding the great earthquake, observed at a little past eleven o’clock in the _northern_ sky, a large meteor of great splendour.” It is remarkable that on this same day, according to the Journal of Science,[7] Copiapó to the _northward_ was visited by a severe earthquake, which on the fifth was followed by a much more violent shock.
Molina[8] states that the first shock which announced the great earthquake at midnight on the 24th of May, 1751, “was accompanied by a ball of fire, which precipitated itself from the Andes toward the sea.” It is said in the Encyclo. Metropol.--(art. _Meteorology_)--“At Kingston, in Jamaica, in November 1812, a large meteor appeared a few minutes previous to some alarming and tremendous concussions.” Aguerros[9] states, on the authority of Ovalle, that in the morning of May 14th, 1633, Carelmapu (north of Chiloe) was overthrown by a bad earthquake, accompanied by a great noise; and that while the people were considering the cause, they saw over a high hill near the village a globe of fire, which appeared to threaten the last day. It rose and quickly proceeded so as to fall in the sea, disturbing the neighbouring waters. This was accompanied by a great tempest, darkness, and a hail-storm, in which pieces of ice fell as large as musket-balls.
I have copied the foregoing notices, because under any point of view, it is remarkable that in one quarter of the globe there should have been so many coincidences between phenomena of not very common occurrence. It must, however, be observed, that the coincidence is not precise; the meteors having been seen in some cases a little before, in others a little after the earthquake. From the account given in Aguerros of the waters of the sea having been disturbed, and from that by Miers of an apparent explosion, it would appear that these meteors must be the same with those that accompany the fall of meteoric stones. This perhaps alone, is an argument that they are accidental accompaniments of earthquakes; for there seems to be no rational method of explaining the origin of meteorolites on any hypothesis directly connected with our world. It is however very singular, that all their constituent parts should be of the same nature as those found on this earth,--that the metals should be chiefly those most subject to magnetic influence,--and that olivine should frequently be present; a mineral[10] which is exclusively confined to a certain class of volcanic products.
To return to the valley of Copiapó. Finding little of interest in this part of the ravine, we retraced our steps to the house of Don Benito, where I staid two days collecting fossil shells and silicified wood. The latter was present in the most extraordinary quantity: it was here that I found a cylindrical trunk, fifteen feet in circumference, projecting from the side of a hill. It was amusing to hear discussions concerning the nature of the fossil shells,--whether or not they had been thus “born by nature,”--carried on almost in the same terms as were used a century before in Europe. My geological examination of the country generally created a good deal of surprise amongst the Chilenos: it was long before they would be convinced that I was not hunting for mines. This was sometimes troublesome. I found the most ready way of explaining my employment, was to ask them how it was that they themselves were not curious concerning earthquakes and volcanoes?--why some springs were hot and others cold?--why there were mountains in Chile, and not a hill in La Plata? These bare questions at once satisfied and silenced the greater number; some, however (like a few in England who are a century behindhand), thought that all such inquiries were useless and impious; and that it was quite sufficient that God had thus made the mountains.
An order had recently been issued that all stray dogs should be killed, and we saw many carcasses lying on the high road. A great number had lately been affected with hydrophobia, and several men had been bitten, and had died in consequence. On other occasions hydrophobia has prevailed in this valley. It is remarkable thus to find so strange and dreadful a disease appearing time after time in the same isolated spot. It has been remarked that certain villages in England are in like manner much more subject to this visitation than others. Hydrophobia must be extremely rare on the eastern side of the Andes, for Azara thought it was unknown in America; and Ulloa says the same with respect to Quito. I could not hear of a case having occurred in Van Diemen’s Land, or in Australia; and Burchell says, during the five years he was at the Cape of Good Hope, he never heard of an instance of it. Webster again asserts that at the Azores, hydrophobia has never occurred; and the same observation has been made with respect to Mauritius and St. Helena.[11] In so strange a disease, some information might possibly be gained by considering the circumstances under which it originates in distant climates. At night, a stranger arrived at the house of Don Benito, and asked permission to sleep there. He said he had been wandering about the mountains for seventeen days, having lost his way. He started from Guasco, and being accustomed to the mountains, did not expect any difficulty in following the track to Copiapó; but he soon became involved in a labyrinth of mountains, whence he could not escape. Some of his mules had fallen over precipices, and he had been in great distress. His chief difficulty arose from not knowing where to find water in the lower country, so that he was obliged to keep bordering the central ranges.
We returned down the valley, and on the 22d reached the town of Copiapó. The lower part of the valley is broad, forming a fine plain like that of Aconcagua or Quillota. The town covers a considerable space of ground, each house possessing a garden: but it is an uncomfortable place, and the dwellings are poorly furnished. Every one seems bent on the one object of making money, and then migrating as quickly as possible. All the inhabitants are more or less directly concerned with mines; and mines and ores are the sole subjects of conversation. Necessaries of all sorts are very dear; as the distance from the town to the port is eighteen leagues, and the land carriage very expensive. A fowl costs five or six shillings; meat is nearly as dear as in England; firewood, or rather sticks, are brought on donkeys from a distance of two and three days’ journey within the Cordillera; and pasturage for animals is a shilling a day: all this for South America is wonderfully exorbitant.
JUNE 26TH.--I hired a guide and eight mules to take me into the Cordillera by a different line from my last expedition. As the country was utterly desert, we took a cargo and a half of barley mixed with chopped straw. About two leagues above the town, a broad valley called the “Despoblado,” or uninhabited, branches off from the one by which we had descended. Although a valley of the grandest dimensions, and leading to a pass across the Cordillera, yet it is completely dry, excepting perhaps, for a few days during some very rainy winter. The bottom of the main valley was nearly flat, and the sides of the crumbling mountains were but little furrowed by ravines. No considerable river could ever have poured its waters over the bed of shingle, without having excavated a channel similar to those occurring in the southern valleys. I feel little doubt that it was left in the state we now see it, by the gradually retiring sea. The dry valleys mentioned by travellers in Peru, probably owe their origin to a similar agency, and not to the running streams of any former period.
I observed in one place, where a ravine (which amongst any other mountains would have been called a grand valley), joined the Despoblado, that the bed of the latter, though composed merely of sand and gravel, was higher than that of its tributary. A mere rivulet of water, in the course of an hour, would have cut a channel for itself; but it was evident that centuries had passed away, and no such rivulet had drained these great valleys. It was curious to behold this machinery (if such a term may be used) for the drainage, all, with the last trifling exception, perfect, yet without any signs of activity. Every one must have remarked how mud-banks, left by the retiring tide, imitate in miniature a country with hill and dale: and here we find a model, only on a grander scale, formed by the waves of a retiring ocean. Let thousands of years replace minutes of the tidal change, and the difference between soft mud and hard rock will barely modify the result. If a shower of rain falls on the mud-bank, when left dry, it deepens the shallow lines of excavation: and so will it be with the rain of successive centuries on the bank of rock and soil, which we call a continent.
We rode on after it was dark, till we reached a side ravine, with a small well called “Agua amarga.” The water deserved its name, for besides being saline it was most offensively putrid and bitter; so that we could not force ourselves to drink either tea or maté. I suppose the distance from the river of Copiapó to this spot was at least twenty-five or thirty English miles; in the whole space there was not a single drop of water, the country almost deserving the name of desert in the strictest sense. Yet about halfway we passed the old Indian ruins near Punta Gorda, which I have already mentioned. I noticed also in front of some of the valleys, which branch off from the Despoblado, two piles of stones placed a little distance apart, and directed so as to point up the mouth of the small valley. My companions knew nothing about them, and only answered my queries by their imperturbable “quien sabe?” JUNE 27TH.--We set out early in the morning, and by mid-day reached the ravine of Paypote, where there is a tiny rill of water, with a little vegetation, and even a few algarroba (a mimosa) trees. On this latter account a smelting furnace had formerly been built here. We found a solitary man in charge of it, whose sole employment was hunting guanacoes. At night it froze sharply; but having plenty of firewood, we kept ourselves warm.
Ideas discussed in this chapter
Text from Project Gutenberg, public domain in the United States.