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Show 48 STEPPES AND DESERTS. term the Llanos a gulf; for, when we consider their small elevation above the present sea level, their form open as it were to the equatorial current sweeping from east to west, and the lowness of the eastern coast between the mouth of the Orinoco and the Essequibo, we can scarcely doubt that the sea once overflowed the whole basin between the coast chain of Caraccas and the Sierra de la Parime, and beat against the mountains of Merida and Pamplona j (as it is supposed to have overflowed the plains of Lombardy, and beat against the Cottian and Pennine Alps.) The strike or inclination of the American Llanos is also directed from east to west. Their height at Calabozo, 400 geographical miles from the sea, is barely 30 toises (192 English feet); being 15 toises (96 English feet) less than that of Pavia, and 45 toises (288 English feet) less than that of Milan, in the plains of Lombardy between the Alps and Apennines. The form of the surface of this part of the globe reminds one of Claudian's expressi-on, "curva.ta tumore parvo planities." The horizontality of the Llanos is so perfect that in many portions of them no part of an area of more than 480 square miles appears to be a foot higher tha.n the rest. If, in addition to this, we ima.gine to ourselves the absence of all bushes, and even in the Mesa de Pavones the absence of any isolated palm trees, it will afford some idea of the singular aspect of this sea-like desert plain. As far as the eye can reach, it can hardly rest on a single object a few inches high. If it were not that the state of the lowest strata of the atmosphere, and the consequent changes of refraction, render the horizon continually indeterminate and undulating, altitudes of the sun might be taken with the sextant from the ma.rgin of the plain as well as from the horizon at sea. This great horizontality of the former sea bottom makes the " banks" more striking. They are broken strata which rise abruptly from two to three feet above the surrounding rock, and extend uniformly over a length of from 40 to 48 English geographical miles. The small streams of the Steppes take their rise on these banks. In passing through the Llanos of Barcelona, on our return from the Rio Negro, we found frequent traces of earthquakes. Instead of the banks standing Mglter than the surrounding rock, we found here solitary strata of gypsum from 3 to 4 toises (19 to 25 English |