France and Lombardy. Yet the vegetation is less vigorous, and the European plants do not grow with the same rapidity as in their natal soil. The winters, at an elevation of 2500 metres, are not extremely rude; but the sun has not sufficient power in summer over the rarefied air of these plains to accelerate the development of flowers, and to bring fruits to perfect maturity. This constant equality, this want of a strong ephemeral heat, imprints a peculiar character on the climate of the higher equinoxial regions. Thus the cultivation of several vegetables succeeds worse on the ridge of the Mexican Cordilleras than in plains situated to the north of the tropic, though frequently the mean heat of these plains is less than that of the plains between the 19° and 22° of latitude. These general considerations on the physical division of New Spain are extremely interesting in a political view. In France, even in the greatest part of Europe, the employment of the soil depends almost entirely on geographical latitude; but in the equinoxial regions of Peru, New Grenada, and Mexico, the climate, productions, aspect, I may say physiognomy, of the country, are solely modified by the elevation of the soil above the level of the sea. The influence of geographical position is absorbed in the effect of this elevation. Lines of cultivation similar to those drawn by Arthur Young and M. Decandolle on the hori zontal projections of France can only be indicated on sections of New Spain. Under the 19° and 22° of latitude, sugar, cotton, particularly cacas and indigo, are only produced abundantly at an elevation of from 6 to 800* metres t The wheat of Europe occupies a zone on the declivity of the mountains, which generally commences at 1400 metres, and ends at 3000 metres. The banana tree (musa paradisiaca), the fruit of which constitutes the principal nourishment of all the inhabitants of the tropics, bears almost no fruit above 1550 metres ; the oaks of Mexico grow only between 800 and 3000 metres ||; and the pines never descend towards the coast of Vera Cruz farther down than 1850 ¶, nor rise near the region of perpetual snow to an elevation of more than 4000 ** metres †t. The provinces called internas, situated in the temperate zone (particularly those included be * From 1968 to 2624 feet. Trans. + I speak here merely of the general distribution of the ve getable productions. I shall afterwards specify places where, favoured by a particular exposure, sugar and cotton may be cultivated 1700 metres (5576 feet) above the ocean. 4592 and 9842 feet. Trans. || Between-2624 and 9842 feet. ¶ 6068 feet. Trans. § 5084 feet. Trans. Trans. ** 13123 feet. Trans. + The reader may consult the section of the road from Mexico to Vera Cruz (plate VI.), and the agricultural scale in my essay on the geography of plants, p. 139. tween the 30° and 38° of latitude) enjoy, like the rest of North America, a climate essentially different from that of the same parallels in the old continent. A remarkable inequality prevails between the temperature of the different seasons. German winters succeed to Neapolitan and Sicilian summers. It would be superfluous to assign here other causes for this phenomenon than the great breadth of the continent and its prolongation towards the north pole. This subject has been discussed by enlightened natural philosophers, particularly by M. Volney, in his excellent work on the soil and climate of the United States, with all the care which it deserves. I shall merely observe that the difference of temperature observable between the same latitudes of Europe and America, is much less remarkable in those parts of the new continent bordering on the Pacific Ocean than in the eastern parts. M. Barton has proved, from the state of agriculture and the natural distribution of vegetables, that the Atlantic provinces are much colder than the extensive plains situated to the west of the Alleghany mountains. A remarkable advantage for the progress of national industry arises from the height at which nature, in New Spain, has deposited the precious metals. In Peru the most considerable silver mines, those of Potosi, Pasco, and Chota, are immensely elevated very near the region of petual snow. In working them, men, provisions, per and cattle must all be brought from a distance. Cities situated in plains, where water freezes the whole year round, and where trees never vegetate, can hardly be an attractive abode. Nothing can determine a free-man to abandon the delicious climate of the vallies to insulate himself on the top of the Andes but the hope of amassing wealth. But in Mexico, the richest seams of silver, those of Guanaxuato, Zacatecas, Tasco, and Real del Monte, are in moderate elevations of from 1700 to 2000 metres*. The mines are surrounded with cultivated fields, towns, and villages; the neighbouring summits are crowned with forests; and every thing facilitates the acquisition of this subterraneous wealth. In the midst of so many advantages bestowed by nature on the kingdom of New Spain, it suffers in general, like Old Spain, from the want of water and navigable rivers. The great river of the north (Rio Bravo del Norte) and the Rio Colorado, are the only rivers worthy of fixing the attention of travellers, either for the length of their course, or the mass of water which they pour into the ocean. The Rio del Norte, from the mountains of the Sierra Verde (to the east of the lake of Timpanogos) to its mouth in the province of New Santander, has a course of 512 leagues. The course of the Rio Colorado is 250. But these two rivers, . *From 5576 to 6561 feet. Trans. situated in the most uncultivated part of the kingdom, can never be interesting for commerce, till great changes in the social order, and other favourable events, introduce colonization into these fertile and temperate regions. These changes are not perhaps very distant. The banks of the Ohio were even in 1797 so thinly inhabited*, that thirty families could hardly be found in a space of 130 leagues, while the habitations are now so multiplied that they are never more than one or two leagues distant from one another. In the whole equinoxial part of Mexico there are only small rivers, the mouths of which are of considerable size. The narrow form of the continent prevents the collection of a great mass of water. The rapid declivity of the Cordillera abounds more properly with torrents than rivers. Mexico is in the same state with Peru, where the Andes approach so near to the coast as to occasion the aridity of the neighbouring plains. Among the small number of rivers in the southern part of New Spain, the only ones which may in time become interesting for interior commerce are, 1. The Rio Guasacualco, and the Rio Alvarado, both to the south-east of Vera Cruz, and adapted for facilitating the communication with the kingdom of Guatimala; 2. The Rio de Moctezuma, which carries the waters of the lakes and valley of Voyage de Michaux a l'ouest des Monts Alleghanys, p. 115. |