S96 



MINERALOGY. 



Deierts. 



Llanos and 

 pampas of 

 South A- 



merica. 



Steppes of 

 Asia and 

 America. 



. its favannahs ; but by this distinction contrasts are 

 '' established, that are not founded either in the nature 

 of things, or the genius of languages. The existence 

 of a heath always supposes an association of plants of 

 the family of erica: the steppes of Asia are not every 

 where covered with saline plants ; the savannahs of 

 Venezuela furnish not only the gramina, but with 

 these small herbaceous mimosas, legumina, and other 

 dicotyledonous plants. The plains of Songaria, those 

 which extend between the Don and the Wolga, and 

 the Puszta of Hungary, are real savannahs, pasturages 

 abounding in grasses ; while the savannahs to the east 

 and west of the Stony mountains, and of New Mesico, 

 produce chenopodiums, containing muriate and carbo- 

 nate of soda. Asia has its real deserts, destitute of ve- 

 getation, in Arabia, in Gobi, and in Persia. Since we 

 have become better acquainted with the deserts in the 

 interior of Africa, so long and so vaguely confounded 

 together under the name of Desert of Sahara (Zahra ;) 

 it has been observed, that in this continent, toward 

 the east, savannahs and pastures are found, as in Ara- 

 bia, set in the midst of naked and barren tracts. It is 

 these last, these deserts covered with gravel, and desti- 

 tute of plants, that are almost entirely awanting in the 

 New World. I saw them only in the low part of 

 Peru, between Amotape and Coguimbo, on the bor- 

 ders of the South Sea. These are called by the Span- 

 iards, not Llanos, but the Dcticrtos of Sechura and 

 Atacamez. This solitary tract is not broad, but 440 

 leagues long. The rock pierces every where through 

 the quicksands. No drop of rain ever falls on it ; and, 

 like the desert of Sahara, to the north of Tombuctoo, 

 the Peruvian desert affords, near Huara, a rich mine of 

 rock-salt. Every where else, in the New World, there 

 are plains, desert because not inhabited, but no real 

 deserts. 



The same phenomena are repeated in the most dis- 

 tant regions ; and, instead of designating those vast 

 plains, destitute of trees, by the nature of the plants 

 they produce, it seems natural to distinguish them into 

 deserts, and steppes or savannahs ; into bare lands with- 

 out any appearance of vegetation, and lands covered 

 with gramina, or small plants of the dicotyledonous 

 tribe. The savannahs of America, especially those of 

 the temperate regions, have, in many works, been de- 

 signaled by the name prairies ; but this term appears 

 to me little applicable to pastures that are often very 

 dry, though covered with grass of four or five feet in 

 height. The llanos and the Pampas of South America 

 are real steppes. They display a beautiful verdure in 

 the rainy season, but in the time of great drought as- 

 sume the aspect of a desert. The grass is then re- 

 duced to powder ; the earth cracks ; the alligator and 

 the great serpents remain buried in the dried mud till 

 awakened from their long lethargy by the first showers 

 of spring. These phenomena are observed in barren 

 tracts of fifty or sixty leagues in length, wherever the 

 savannahs are not traversed by rivers ; for on the bor- 

 ders of rivulets, and around little pools of stagnant wa- 

 ter, the traveller finds, at certain distances, even during 

 the period of the great droughts, thickets of mauntia, 

 a palm, the leaves of which, spread out like a fan, 

 preserve a brilliant verdure. 



The steppes of Asia are all beyond the tropics, and 

 form very elevated table-lands. America, also, display s sa- 

 vannahs of considerable extent'on the backs of the moun- 

 tains of Mexico, Peru, and Quito ; but its most extensive 

 steppes, the Llanos of Cumana, Caraccas and Meta, are 

 "e raised above the level of the ocean, and all belong 



to the equinoctial zone. These circumstances give them Geognosy. 

 a peculiar character. They have not, like the steppes ^ V^ 1 ' 

 of southern Asia, and the deserts of Persia, those lakes 

 without issue, those small systems of rivers, that lose 

 themselves either in the sands, or by subterraneous fil- 

 trations. The Llanos of America are inclined towards 

 the east and south, and their running waters are branch- 

 es of the Oroonoko. 



The course of these rivers had once led me to believe 

 that the plains formed table- lands, raised at least from 

 one hundred to one hundred and fifty toises above the 

 level of the ocean. I supposed that the deserts of in- 

 terior Africa were also at a considerable height ; and 

 that they rose one above another, like stages," from the 

 coast to the interior of the continent. No barometer 

 has yet been carried into the Sahara. With respect to 

 the llanos of America, I found by barometric heights, 

 observed at Calabozo, at the Villa del Pao, and at the 

 mouth of the Meta, that their height is only 40 or 50 

 toises above the level of the sea. The fall of the river 

 is extremely gentle, often nearly imperceptible ; and, 

 therefore, the least wind, or the swelling of the Oroo- 

 noko, causes a reflux in those rivers that flow into it. 

 The Indians believe they descend during a whole day 

 in navigating from their mouths toward their sources. 

 The waters that descend are separated from those that 

 flow back by a great body of stagnant water, in which 

 the equilibrium being disturbed, whirlpools are formed 

 that are dangerous for boats. 



The chief characteristic of the savannahs, or steppes Characters 

 of South America, is the absolute want of hills and ine- of South ' 

 qualties, the perfect level of every part of the soil. American 

 Often in a space of thirty leagues there is not an emi- steppes. 

 nence of a foot high. This resemblance to the surface 

 of the ocean strikes the imagination most powerfully, 

 where the plains are altogether destitute of palm-trees ; 

 and where the mountains of the shore, and of the Oro- 

 nooko are so far distant, that they cannot be seen, as in 

 the Mesa de Pavones. The equality of surface is still 

 more perfect in the meridian of Calabozo than towards 

 the east, between the Cari, La Villa del Pao, and Nueva 

 Barcelona ; but it reigns without interruption from the 

 mouths of the Oronooko to Lavella de Araure and Os- 

 pinos, under a parallel of an hundred and eighty leagues 

 in length ; and from San Carlos to the savannahs of 

 Caqueta, on a meridian of two hundred leagues. It 

 particularly characterises the new continent, as it does 

 the low steppes of Asia, between the Borysthenes and the 

 Wolga, between the Irtisch and the Obi. The deserts 

 of central Africa, of Arabia, Syria, and Persia, Cobi, 

 and Casna, present, on the contrary, many inequalities, 

 ranges of hills, ravines without water, and rocks that 

 pierce the sands. 



The llanos, however, notwithstanding the apparent 

 uniformity of their surface, furnish two kinds of ine- 

 qualities that do not escape the observation of an at- 

 tentive observer. The first is known by the name 

 Buncos ; they are real shoals in the basin of the steppes, 

 fractured strata of sandstone, or compact limestone stand- 

 ing four or five feet higher than the rest of the plain. 

 These banks are sometimes three or four leagues in 

 length ; they are entirely smooth, with a horizontal sur- 

 face; theirexistence is only perceived by examining their 

 borders. The second species of inequality can be re- 

 cognised only by geodesical or barometric levellings, or 

 by the course of rivers. It is called Mesa, and is com- 

 posed of small flats, or rather convex eminences, that 

 rise insensibly to the height of a few toises. 



The uniform landscape of the llanos ; the extreme 





