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respect resembling the Carranchas) wait at the mouth of a

rabbit-hole, and together seize on the animal when it comes out. They were constantly flying on board the vessel when in the harbour; and it was necessary to keep a good lookout to prevent the leather being torn from the rigging, and the meat or game from the stern. These birds are very mischievous and inquisitive; they

will pick up almost anything from the ground; a large black glazed

hat was carried nearly a mile, as was a pair of the heavy balls

used in catching cattle. Mr. Usborne experienced during the survey

a more severe loss, in their stealing a small Kater's compass in a red morocco leather case, which was never recovered. These birds

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are, moreover, quarrelsome and very passionate; tearing up the

grass with their bills from rage. They are not truly gregarious; they do not soar, and their flight is heavy and clumsy; on the ground they run extremely fast, very much like pheasants. They are noisy, uttering several harsh cries, one of which is like that of

the English rook, hence the sealers always call them rooks. It is a curious circumstance that, when crying out, they throw their heads upwards and backwards, after the same manner as the Carrancha. They build in the rocky cliffs of the sea-coast, but only on the small

adjoining islets, and not on the two main islands: this is a

singular precaution in so tame and fearless a bird. The sealers say that the flesh of these birds, when cooked, is quite white, and very good eating; but bold must the man be who attempts such a meal.

We have now only to mention the turkey-buzzard (Vultur aura), and the Gallinazo. The former is found wherever the country is

moderately damp, from Cape Horn to North America. Differently from the Polyborus Brasiliensis and Chimango, it has found its way to

the Falkland Islands. The turkey-buzzard is a solitary bird, or at

most goes in pairs. It may at once be recognised from a long distance, by its lofty, soaring, and most elegant flight. It is well known to be a true carrion-feeder. On the west coast of

Patagonia, among the thickly-wooded islets and broken land, it

lives exclusively on what the sea throws up, and on the carcasses

of dead seals. Wherever these animals are congregated on the rocks,

there the vultures may be seen. The Gallinazo (Cathartes atratus) has a different range from the last species, as it never occurs southward of latitude 41 degrees. Azara states that there exists a

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tradition that these birds, at the time of the conquest, were not found near Monte Video, but that they subsequently followed the inhabitants from more northern districts. At the present day they are numerous in the valley of the Colorado, which is three hundred miles due south of Monte Video. It seems probable that this

additional migration has happened since the time of Azara. The

Gallinazo generally prefers a humid climate, or rather the neighbourhood of fresh water; hence it is extremely abundant in Brazil and La Plata, while it is never found on the desert and arid plains of Northern Patagonia, excepting near some stream. These birds frequent the whole Pampas to the foot of the Cordillera, but I never saw or heard of one in Chile: in Peru they are preserved as scavengers. These vultures certainly may be called gregarious, for they seem to have pleasure in society, and are not solely brought together by the attraction of a common prey. On a fine day a flock may often be observed at a great height, each bird wheeling round and round without closing its wings, in the most graceful evolutions. This is clearly performed for the mere pleasure of the exercise, or perhaps is connected with their matrimonial alliances.

I have now mentioned all the carrion-feeders, excepting the condor, an account of which will be more appropriately introduced when we visit a country more congenial to its habits than the plains of La Plata.

In a broad band of sand-hillocks which separate the Laguna del

Potrero from the shores of the Plata, at the distance of a few

miles from Maldonado, I found a group of those vitrified, siliceous

tubes, which are formed by lightning entering loose sand. These

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tubes resemble in every particular those from Drigg in Cumberland, described in the "Geological Transactions." (3/10. "Geological Transactions" volume 2 page 528. In the "Philosophical Transactions" 1790 page 294, Dr. Priestley has described some

imperfect siliceous tubes and a melted pebble of quartz, found in

digging into the ground, under a tree, where a man had been killed by lightning.) The sand-hillocks of Maldonado, not being protected by vegetation, are constantly changing their position. From this

cause the tubes projected above the surface; and numerous fragments

lying near, showed that they had formerly been buried to a greater depth. Four sets entered the sand perpendicularly: by working with my hands I traced one of them two feet deep; and some fragments which evidently had belonged to the same tube, when added to the other part, measured five feet three inches. The diameter of the whole tube was nearly equal, and therefore we must suppose that originally it extended to a much greater depth. These dimensions

are however small, compared to those of the tubes from Drigg, one of which was traced to a depth of not less than thirty feet.

The internal surface is completely vitrified, glossy, and smooth. A small fragment examined under the microscope appeared, from the number of minute entangled air or perhaps steam bubbles, like an assay fused before the blowpipe. The sand is entirely, or in

greater part, siliceous; but some points are of a black colour, and from their glossy surface possess a metallic lustre. The thickness of the wall of the tube varies from a thirtieth to a twentieth of

an inch, and occasionally even equals a tenth. On the outside the grains of sand are rounded, and have a slightly glazed appearance: I could not distinguish any signs of crystallisation. In a similar

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manner to that described in the "Geological Transactions," the

tubes are generally compressed, and have deep longitudinal furrows, so as closely to resemble a shrivelled vegetable stalk, or the bark

of the elm or cork tree. Their circumference is about two inches, but in some fragments, which are cylindrical and without any furrows, it is as much as four inches. The compression from the surrounding loose sand, acting while the tube was still softened from the effects of the intense heat, has evidently caused the creases or furrows. Judging from the uncompressed fragments, the

measure or bore of the lightning (if such a term may be used) must have been about one inch and a quarter. At Paris, M. Hachette and M. Beudant succeeded in making tubes, in most respects similar to these fulgurites, by passing very strong shocks of galvanism

through finely-powdered glass: when salt was added, so as to

increase its fusibility, the tubes were larger in every dimension.

(3/11. "Annales de Chimie et de Physique" tome 37 page 319.) They failed both with powdered feldspar and quartz. One tube, formed with pounded glass, was very nearly an inch long, namely .982, and had an internal diameter of .019 of an inch. When we hear that the strongest battery in Paris was used, and that its power on a

substance of such easy fusibility as glass was to form tubes so diminutive, we must feel greatly astonished at the force of a shock of lightning, which, striking the sand in several places, has

formed cylinders, in one instance of at least thirty feet long, and having an internal bore, where not compressed, of full an inch and

a half; and this in a material so extraordinarily refractory as

quartz!

The tubes, as I have already remarked, enter the sand nearly in a

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vertical direction. One, however, which was less regular than the others, deviated from a right line, at the most considerable bend, to the amount of thirty-three degrees. From this same tube, two

small branches, about a foot apart, were sent off; one pointed

downwards, and the other upwards. This latter case is remarkable,

as the electric fluid must have turned back at the acute angle of

26 degrees, to the line of its main course. Besides the four tubes which I found vertical, and traced beneath the surface, there were several other groups of fragments, the original sites of which without doubt were near. All occurred in a level area of shifting sand, sixty yards by twenty, situated among some high

sand-hillocks, and at the distance of about half a mile from a chain of hills four or five hundred feet in height. The most remarkable circumstance, as it appears to me, in this case as well as in that of Drigg, and in one described by M. Ribbentrop in

Germany, is the number of tubes found within such limited spaces. At Drigg, within an area of fifteen yards, three were observed, and the same number occurred in Germany. In the case which I have described, certainly more than four existed within the space of the sixty by twenty yards. As it does not appear probable that the

tubes are produced by successive distinct shocks, we must believe that the lightning, shortly before entering the ground, divides itself into separate branches.

The neighbourhood of the Rio Plata seems peculiarly subject to electric phenomena. In the year 1793, one of the most destructive thunderstorms perhaps on record happened at Buenos Ayres: thirty-seven places within the city were struck by lightning, and

nineteen people killed. (3/12. Azara's "Voyage" volume 1 page 36.)

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From facts stated in several books of travels, I am inclined to

suspect that thunderstorms are very common near the mouths of great

rivers. Is it not possible that the mixture of large bodies of

fresh and salt water may disturb the electrical equilibrium? Even during our occasional visits to this part of South America, we

heard of a ship, two churches, and a house having been struck. Both the church and the house I saw shortly afterwards: the house belonged to Mr. Hood, the consul-general at Monte Video. Some of the effects were curious: the paper, for nearly a foot on each side

of the line where the bell-wires had run, was blackened. The metal had been fused, and although the room was about fifteen feet high, the globules, dropping on the chairs and furniture, had drilled in

them a chain of minute holes. A part of the wall was shattered as

if by gunpowder, and the fragments had been blown off with force sufficient to dent the wall on the opposite side of the room. The frame of a looking-glass was blackened, and the gilding must have been volatilised, for a smelling-bottle, which stood on the

chimney-piece, was coated with bright metallic particles, which

adhered as firmly as if they had been enamelled.

(PLATE 17. HALT AT A PULPERIA ON THE PAMPAS.)

CHAPTER IV.

(PLATE 18. EL CARMEN, OR PATAGONES, RIO NEGRO.)

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Rio Negro.

Estancias attacked by the Indians. Salt Lakes.

Flamingoes.

R. Negro to R. Colorado. Sacred Tree.

Patagonian Hare. Indian Families. General Rosas.

Proceed to Bahia Blanca. Sand Dunes.

Negro Lieutenant. Bahia Blanca.

Saline Incrustations. Punta Alta.

Zorillo.

RIO NEGRO TO BAHIA BLANCA.

JULY 24, 1833.

The "Beagle" sailed from Maldonado, and on August the 3rd she arrived off the mouth of the Rio Negro. This is the principal river on the whole line of coast between the Strait of Magellan and the Plata. It enters the sea about three hundred miles south of the estuary of the Plata. About fifty years ago, under the old Spanish government, a small colony was established here; and it is still

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the most southern position (latitude 41 degrees) on this eastern coast of America inhabited by civilised man.

The country near the mouth of the river is wretched in the extreme: on the south side a long line of perpendicular cliffs commences, which exposes a section of the geological nature of the country.

The strata are of sandstone, and one layer was remarkable from

being composed of a firmly-cemented conglomerate of pumice pebbles, which must have travelled more than four hundred miles, from the Andes. The surface is everywhere covered up by a thick bed of

gravel, which extends far and wide over the open plain. Water is extremely scarce, and, where found, is almost invariably brackish. The vegetation is scanty; and although there are bushes of many kinds, all are armed with formidable thorns, which seem to warn the stranger not to enter on these inhospitable regions.

The settlement is situated eighteen miles up the river. The road follows the foot of the sloping cliff, which forms the northern boundary of the great valley in which the Rio Negro flows. On the way we passed the ruins of some fine estancias, which a few years since had been destroyed by the Indians. They withstood several attacks. A man present at one gave me a very lively description of what took place. The inhabitants had sufficient notice to drive all the cattle and horses into the corral which surrounded the house, and likewise to mount some small cannon. (4/1. The corral is an enclosure made of tall and strong stakes. Every estancia, or

farming estate, has one attached to it.)

The Indians were Araucanians from the south of Chile; several

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hundreds in number, and highly disciplined. They first appeared in

two bodies on a neighbouring hill; having there dismounted, and

taken off their fur mantles, they advanced naked to the charge. The

only weapon of an Indian is a very long bamboo or chuzo, ornamented

with ostrich feathers, and pointed by a sharp spear-head. My

informer seemed to remember with the greatest horror the quivering of these chuzos as they approached near. When close, the cacique Pincheira hailed the besieged to give up their arms, or he would

cut all their throats. As this would probably have been the result

of their entrance under any circumstances, the answer was given by a volley of musketry. The Indians, with great steadiness, came to

the very fence of the corral: but to their surprise they found the posts fastened together by iron nails instead of leather thongs, and, of course, in vain attempted to cut them with their knives.

This saved the lives of the Christians: many of the wounded Indians were carried away by their companions, and at last, one of the

under caciques being wounded, the bugle sounded a retreat. They retired to their horses, and seemed to hold a council of war. This was an awful pause for the Spaniards, as all their ammunition, with

the exception of a few cartridges, was expended. In an instant the

Indians mounted their horses, and galloped out of sight. Another attack was still more quickly repulsed. A cool Frenchman managed the gun; he stopped till the Indians approached close, and then raked their line with grape-shot: he thus laid thirty-nine of them

on the ground; and, of course, such a blow immediately routed the

whole party.

The town is indifferently called El Carmen or Patagones. It is built on the face of a cliff which fronts the river, and many of

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the houses are excavated even in the sandstone. The river is about

two or three hundred yards wide, and is deep and rapid. The many islands, with their willow-trees, and the flat headlands, seen one behind the other on the northern boundary of the broad green valley, form, by the aid of a bright sun, a view almost

picturesque. The number of inhabitants does not exceed a few hundreds. These Spanish colonies do not, like our British ones, carry within themselves the elements of growth. Many Indians of pure blood reside here: the tribe of the Cacique Lucanee constantly have their Toldos on the outskirts of the town. (4/2. The hovels of the Indians are thus called.) The local government partly supplies them with provisions, by giving them all the old worn-out horses, and they earn a little by making horse-rugs and other articles of riding-gear. These Indians are considered civilised; but what their character may have gained by a lesser degree of ferocity, is almost

counterbalanced by their entire immorality. Some of the younger men

are, however, improving; they are willing to labour, and a short

time since a party went on a sealing-voyage, and behaved very well. They were now enjoying the fruits of their labour, by being dressed in very gay, clean clothes, and by being very idle. The taste they showed in their dress was admirable; if you could have turned one of these young Indians into a statue of bronze, his drapery would have been perfectly graceful.

One day I rode to a large salt-lake, or Salina, which is distant fifteen miles from the town. During the winter it consists of a shallow lake of brine, which in summer is converted into a field of snow-white salt. The layer near the margin is from four to five inches thick, but towards the centre its thickness increases. This

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lake was two and a half miles long, and one broad. Others occur in the neighbourhood many times larger, and with a floor of salt, two and three feet in thickness, even when under water during the

winter. One of these brilliantly white and level expanses, in the

midst of the brown and desolate plain, offers an extraordinary spectacle. A large quantity of salt is annually drawn from the salina: and great piles, some hundred tons in weight, were lying ready for exportation.

The season for working the salinas forms the harvest of Patagones; for on it the prosperity of the place depends. Nearly the whole population encamps on the bank of the river, and the people are employed in drawing out the salt in bullock-waggons. This salt is crystallised in great cubes, and is remarkably pure: Mr. Trenham Reeks has kindly analysed some for me, and he finds in it only 0.26 of gypsum and 0.22 of earthy matter. It is a singular fact that it

does not serve so well for preserving meat as sea-salt from the

Cape de Verd islands; and a merchant at Buenos Ayres told me that he considered it as fifty per cent less valuable. Hence the Cape de Verd salt is constantly imported, and is mixed with that from these salinas. The purity of the Patagonian salt, or absence from it of those other saline bodies found in all sea-water, is the only assignable cause for this inferiority: a conclusion which no one, I think, would have suspected, but which is supported by the fact lately ascertained, that those salts answer best for preserving

cheese which contain most of the deliquescent chlorides. (4/3. Report of the Agricultural Chemistry Association in the "Agricultural Gazette" 1845 page 93.)

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The border of the lake is formed of mud: and in this numerous large crystals of gypsum, some of which are three inches long, lie

embedded; whilst on the surface others of sulphate of soda lie

scattered about. The Gauchos call the former the "Padre del sal," and the latter the "Madre;" they state that these progenitive salts always occur on the borders of the salinas, when the water begins to evaporate. The mud is black, and has a fetid odour. I could not at first imagine the cause of this, but I afterwards perceived that

the froth which the wind drifted on shore was coloured green, as if by confervae; I attempted to carry home some of this green matter, but from an accident failed. Parts of the lake seen from a short distance appeared of a reddish colour, and this perhaps was owing

to some infusorial animalcula. The mud in many places was thrown up by numbers of some kind of worm, or annelidous animal. How surprising it is that any creatures should be able to exist in

brine, and that they should be crawling among crystals of sulphate

of soda and lime! And what becomes of these worms when, during the

long summer, the surface is hardened into a solid layer of salt?

Flamingoes in considerable numbers inhabit this lake, and breed

here, throughout Patagonia, in Northern Chile, and at the Galapagos

Islands, I met with these birds wherever there were lakes of brine. I saw them here wading about in search of food--probably for the worms which burrow in the mud; and these latter probably feed on infusoria or confervae. Thus we have a little living world within itself, adapted to these inland lakes of brine. A minute

crustaceous animal (Cancer salinus) is said to live in countless numbers in the brine-pans at Lymington: but only in those in which the fluid has attained, from evaporation, considerable

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strength--namely, about a quarter of a pound of salt to a pint of water. (4/4. "Linnaean Transactions" volume 11 page 205. It is remarkable how all the circumstances connected with the salt-lakes in Siberia and Patagonia are similar. Siberia, like Patagonia,

appears to have been recently elevated above the waters of the sea. In both countries the salt-lakes occupy shallow depressions in the

plains; in both the mud on the borders is black and fetid; beneath

the crust of common salt, sulphate of soda or of magnesia occurs, imperfectly crystallised; and in both, the muddy sand is mixed with lentils of gypsum. The Siberian salt-lakes are inhabited by small crustaceous animals; and flamingoes ("Edinburgh New Philosical Journal" January 1830) likewise frequent them. As these circumstances, apparently so trifling, occur in two distant continents, we may feel sure that they are the necessary results of common causes.--See "Pallas's Travels" 1793 to 1794 pages 129 to

134.) Well may we affirm that every part of the world is habitable! Whether lakes of brine, or those subterranean ones hidden beneath volcanic mountains--warm mineral springs--the wide expanse and depths of the ocean--the upper regions of the atmosphere, and even the surface of perpetual snow--all support organic beings.

To the northward of the Rio Negro, between it and the inhabited country near Buenos Ayres, the Spaniards have only one small settlement, recently established at Bahia Blanca. The distance in a straight line to Buenos Ayres is very nearly five hundred British miles. The wandering tribes of horse Indians, which have always occupied the greater part of this country, having of late much harassed the outlying estancias, the government at Buenos Ayres

equipped some time since an army under the command of General Rosas

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for the purpose of exterminating them. The troops were now encamped

on the banks of the Colorado; a river lying about eighty miles

northward of the Rio Negro. When General Rosas left Buenos Ayres he

struck in a direct line across the unexplored plains: and as the country was thus pretty well cleared of Indians, he left behind him, at wide intervals, a small party of soldiers with a troop of horses (a posta), so as to be enabled to keep up a communication with the capital. As the "Beagle" intended to call at Bahia Blanca,

I determined to proceed there by land; and ultimately I extended my

plan to travel the whole way by the postas to Buenos Ayres.

AUGUST 11, 1833.

Mr. Harris, an Englishman residing at Patagones, a guide, and five Gauchos who were proceeding to the army on business, were my companions on the journey. The Colorado, as I have already said, is nearly eighty miles distant: and as we travelled slowly, we were

two days and a half on the road. The whole line of country deserves scarcely a better name than that of a desert. Water is found only

in two small wells; it is called fresh; but even at this time of

the year, during the rainy season, it was quite brackish. In the summer this must be a distressing passage; for now it was sufficiently desolate.

The valley of the Rio Negro, broad as it is, has merely been

excavated out of the sandstone plain; for immediately above the

bank on which the town stands, a level country commences, which is

interrupted only by a few trifling valleys and depressions. Everywhere the landscape wears the same sterile aspect; a dry

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gravelly soil supports tufts of brown withered grass, and low scattered bushes, armed with thorns.

Shortly after passing the first spring we came in sight of a famous tree, which the Indians reverence as the altar of Walleechu. It is situated on a high part of the plain; and hence is a landmark visible at a great distance. As soon as a tribe of Indians come in sight of it, they offer their adorations by loud shouts. The tree itself is low, much branched, and thorny: just above the root it

has a diameter of about three feet. It stands by itself without any neighbour, and was indeed the first tree we saw; afterwards we met with a few others of the same kind, but they were far from common. Being winter the tree had no leaves, but in their place numberless threads, by which the various offerings, such as cigars, bread,

meat, pieces of cloth, etc., had been suspended. Poor Indians, not having anything better, only pull a thread out of their ponchos, and fasten it to the tree. Richer Indians are accustomed to pour spirits and mate into a certain hole, and likewise to smoke upwards, thinking thus to afford all possible gratification to Walleechu. To complete the scene, the tree was surrounded by the

bleached bones of horses which had been slaughtered as sacrifices. All Indians of every age and sex make their offerings; they then think that their horses will not tire, and that they themselves

shall be prosperous. The Gaucho who told me this, said that in the time of peace he had witnessed this scene, and that he and others used to wait till the Indians had passed by, for the sake of

stealing from Walleechu the offerings.

The Gauchos think that the Indians consider the tree as the god

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itself; but it seems far more probable that they regard it as the

altar. The only cause which I can imagine for this choice, is its being a landmark in a dangerous passage. The Sierra de la Ventana

is visible at an immense distance; and a Gaucho told me that he was

once riding with an Indian a few miles to the north of the Rio Colorado, when the Indian commenced making the same loud noise, which is usual at the first sight of the distant tree, putting his

hand to his head, and then pointing in the direction of the Sierra. Upon being asked the reason of this, the Indian said in broken Spanish, "First see the Sierra."

About two leagues beyond this curious tree we halted for the night: at this instant an unfortunate cow was spied by the lynx-eyed Gauchos, who set off in full chase, and in a few minutes dragged her in with their lazos, and slaughtered her. We here had the four necessaries of life "en el campo,"--pasture for the horses, water

(only a muddy puddle), meat and firewood. The Gauchos were in high

spirits at finding all these luxuries; and we soon set to work at the poor cow. This was the first night which I passed under the open sky, with the gear of the recado for my bed. There is high

enjoyment in the independence of the Gaucho life--to be able at any moment to pull up your horse, and say, "Here we will pass the

night." The deathlike stillness of the plain, the dogs keeping

watch, the gipsy-group of Gauchos making their beds round the fire, have left in my mind a strongly-marked picture of this first night, which will never be forgotten.

The next day the country continued similar to that above described.

It is inhabited by few birds or animals of any kind. Occasionally a

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deer, or a Guanaco (wild Llama) may be seen; but the Agouti (Cavia

Patagonica) is the commonest quadruped. This animal here represents our hares. It differs, however, from that genus in many essential respects; for instance, it has only three toes behind. It is also

nearly twice the size, weighing from twenty to twenty-five pounds. The Agouti is a true friend of the desert; it is a common feature

of the landscape to see two or three hopping quickly one after the other in a straight line across these wild plains. They are found

as far north as the Sierra Tapalguen (latitude 37 degrees 30'),

where the plain rather suddenly becomes greener and more humid; and

their southern limit is between Port Desire and St. Julian, where there is no change in the nature of the country.

It is a singular fact, that although the Agouti is not now found as far south as Port St. Julian, yet that Captain Wood, in his voyage

in 1670, talks of them as being numerous there. What cause can have altered, in a wide, uninhabited, and rarely-visited country, the

range of an animal like this? It appears also, from the number shot

by Captain Wood in one day at Port Desire, that they must have been considerably more abundant there formerly than at present. Where the Bizcacha lives and makes its burrows, the Agouti uses them; but where, as at Bahia Blanca, the Bizcacha is not found, the Agouti burrows for itself. The same thing occurs with the little owl of

the Pampas (Athene cunicularia), which has so often been described

as standing like a sentinel at the mouth of the burrows; for in Banda Oriental, owing to the absence of the Bizcacha, it is obliged to hollow out its own habitation.

The next morning, as we approached the Rio Colorado, the appearance

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of the country changed; we soon came on a plain covered with turf,

which, from its flowers, tall clover, and little owls, resembled

the Pampas. We passed also a muddy swamp of considerable extent, which in summer dries, and becomes incrusted with various salts; and hence is called a salitral. It was covered by low succulent

plants, of the same kind with those growing on the sea-shore. The

Colorado, at the pass where we crossed it, is only about sixty yards wide; generally it must be nearly double that width. Its course is very tortuous, being marked by willow-trees and beds of reeds: in a direct line the distance to the mouth of the river is

said to be nine leagues, but by water twenty-five. We were delayed crossing in the canoe by some immense troops of mares, which were swimming the river in order to follow a division of troops into the interior. A more ludicrous spectacle I never beheld than the

hundreds and hundreds of heads, all directed one way, with pointed ears and distended snorting nostrils, appearing just above the

water like a great shoal of some amphibious animal. Mare's flesh is

the only food which the soldiers have when on an expedition. This gives them a great facility of movement; for the distance to which horses can be driven over these plains is quite surprising: I have been assured that an unloaded horse can travel a hundred miles a day for many days successively.