Page:The American Cyclopædia (1879) Volume I.djvu/725

 ARGENTIKE EEPUBLIC 689 gical features of the regions N". of the Plata present a striking contrast with those on the south. The former are elevated, and com- posed of granite, gneiss, and clay slate; and indeed all the rocks showing themselves above the plain of the Plata, in the Sierra Ventana S. of Buenos Ayres, in Entre-Rios, C6rdoba, and the upper provinces generally, are granitic, a superposition of pure white quartz rock as- sociated with glossy clay slate occurring, how- ever, over the granite of the Ventana. On the S. side of the Plata all rock formations disappear, and not even a pebble is to be found for hundreds of miles inland. The pam- psean regions are characterized by a diluvial formation consisting of calcareo-argillaceous conglomerate gradually deposited during the lapse of ages, in what was once an arm of the Atlantic, but is now dwindled within the pres- ent limits of the estuary of the Plata. It may be observed that this same deposition is still rapidly progressing in the bed of the river, in- eomuch that it is altogether likely that the great stream which, according to report, was navigable for ships of the heaviest burthen three centuries ago, will in the course of ages flow into the ocean by a delta, like the Nile or the Ganges, instead of entering it, as it now does, through a single mouth. In Entre-Rios there occur at the bottom of the cliffs beds containing sharks' teeth and sea shells of ex- tinct species, passing above into an indurated marl, and from that into the red clayey earth of the pampas, with its calcareous concretions and the bones of terrestrial quadrupeds, clearly telling of a large bay of pure salt water, grad- ually encroached on, and at last converted into a muddy estuary into which floating carcasses were swept. The number of the fossil remains imbedded in the grand estuary deposit, says Darwin, must be extraordinarily great. A line drawn in any direction through these regions would, observes the same writer, cut through some skeleton or bones. Fossil mammalia of nine species have been found: the megathe- rium, of huge dimensions ; the megalonyx and scelidotherium, the latter edentate and prob- ably as large as a rhinoceros, and both allied to the first; the mylodon Darwinii, and another gigantic edentate quadruped; a large animal with an osseous coat in compartments, bearing some resemblance to the armadillo ; an extinct kind of horse, the equus curvidens, indicative of the existence and disappearance of a native race before the introduction of the few indi- viduals by the Spanish colonists ; a pachyder- matous animal, perhaps the same with the macrauchenia ; and the toxodon, an elephant in size, a gnawer by the structure of the teeth, and probably aquatic like the manatee, to which it is allied. The Aconquija mountain chain abounds in gold, silver, and copper ores ; and the Famatina in La Rioja affords very fine silver ores. Iron has been found" in the Gran Chaco. An immense mass of this metal, pre- sented by Sir W. Parish to the British museum, 45 VOL. i. 45 and pronounced to be of meteoric origin, is re- garded by him as a genuine production of the soil. Salt, the most abundant mineral in the Argentine Republic, exists in a state of efflores- cence covering immense tracts, and in count- less brackish springs and pools ; but nowhere is it so common as near Bahia Blanca. The salt occurring far inland consists for the most part of sulphate of soda, and perhaps 7 per cent, of common salt, and does not preserve meat well ; while near the coast the proportion of common salt reaches 37 per cent., and the quality is superior. There are besides mines of rock salt in the country ; and sulphate of soda and sulphate of magnesia, from which the magnesia of commerce is prepared, occur in various localities. Coal is found in the N". "W. provinces, also gypsum, limestone, alum, min- eral pitch, bituminous shale, and large quanti- ties of sulphur ; and there are extensive coal beds in the extreme S. W. angle of the country. The climate, on the whole perhaps "one of the finest in the world, exhibits nevertheless considerable variety. In the north the heat is great, and in some localities oppressive, save where tempered by fresh breezes from the Andes. On travelling southward a cooler tem- perature is experienced, and especially in the province of Buenos Ayres, where the climate closely resembles that of some portions of south- ern Europe. In the plains reaching from the Andes to the banks of the Parana there is a great deficiency of moisture, while the coun- tries E. of that river are refreshed by abundant and frequent rains. In Buenos Ayres, where a luxuriant vegetation shows great humidity, the climate is chiefly governed by the wind, a change of which not infrequently brings an alteration of from 20 to 30 in the thermom- eter, which rarely rises above 90 in the shade. The prevailing winds are northerly, and these, passing over extensive marshy and saline dis- tricts, produce on reaching Buenos Ayres a universal dampness, and upon the bodily sys- tem an extreme lassitude, inducing a liability to all the maladies consequent upon checked perspiration. Although the northers are not generally regarded as unfavorable to health if the necessary precautions are taken, while they prevail the most trifling wound or hurt may terminate in lockjaw. The S. W. wind, or pampero, usually follows the norther, and blows at times with great violence, driving back the waters of the Plata miles from the shore, and bearing clouds of dust so dense as to produce total darkness. The pamperos very frequently end in a heavy shower of rain, or rather mud, formed by the mingling of the water and the dust. The thunder and lightning during one of these storms are perhaps unequalled in any other part of the world. A disease called el mal de siete dias (the seven days' sickness), mainly prevalent among the lower classes, carries off an immense number of infants in the first week after birth. The following table shows the range of Fahrenheit's ther-