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especially in the provincias internas. We have already explained* the reason why these mines, the most important of all, are only wrought with any degree of spirit during a period of maritime war, when a stop is put to the importation of steel and iron from Europe; and we have already named the veins of Tecalitan, near Colima, which were suceessfully wrought ten years ago, and afterwards abandoned. Fibrous magnetic iron is found in conjunction with magnetic pyrite in veins which traverse gneiss in the kingdom of Oaxaca. The western slope of the mouna tains of Mechoacan abounds in ores of compact red iron and hematite brown iron. The former have also been observed in the intendancy of San Luis Potosi near Catorce. I saw christalized micaceous iron, near the village of Santa Cruz, east from Celaya, on the fertile table land extending from Queretaro to Guanaxuato. The Cerro del Mercado, situated near the town of Durango, contains an enormous · mass of ores of brown magnetic and micaceous iron. I enter into the detail of these localities for the sake of proving the falsity of the opinion delivered by several modern natural philosophers, that iron almost exclusively belongs to the most northern regions of the temperate zone. To
* See p. 106 of this volume.
M. Sonneschmidt we owe the knowledge of the meteoric iron*, which is found in several places of New Spain, for example at Zacatecas, Charcas, Durango, and if I am not deceived in the environs of the small town of Toluca.
Lead, which is very rare in the north of Asia, abounds in the mountains of calcareous formation, contained in the north east part of New Spain, especially in the district of Zimapan, near the Real del Cardonal and Lomo del Toro; in the kingdom of New Leon, near Linares; and in the province of New Santander, near St. Nicholas de Croix. The lead mines are not wrought with so much spirit as we could wish for in a country where the fourth part of all the silver minerals are smelted.
Among the metals, of which the use is the most limited, we have to name zinc, which is found, under the form of brown and black blende in the veins of Ramos, Sombrerete, Zacatecas, and Tasco; antimony, which is common to Catorce and los Pozuelos, near Cuencame; arsenic, which is found among the minerals of Zinapan, combined with sulphur, like orpiment. Cobalt, as far as I know, has never yet been discovered among the minerals of New Spain; and manganese*, which M. Ramirez recently discovered in the Island of Cuba, appears to me in general much less abundant in Equinoctial America, than in the temperate climates of the Old Continent.
* Sonneschmidt, p. 188 and 192. The mass of Zacatecas still weighed ten years ago, near 2000 lib. See a memoir of M. Chladni in the Journal des Mines, 1809, no. 151, p. 79, relative to a meteoric stone, which fell between Cicuic and Quivira according to the testimony of Cardanus and Mercati. The geographical position of Cicuic and Quivira, names which recal to us the fables of the El Dorado of South America, remains still unknown.
Mercury, which is very remote from tin, with respect to its relative antiquity, or the period of its formation, is almost as uncommon as it, in every part of the globe. The inhabitants of New Spain have procured for centuries, the mercury necessary in the process of amalgamation, partly from Peru, and partly from Europe; and hence they are accustomed to consider their country as destitute of this metal However, when we consider the examinations carried on under the reign of Charles the 4th, we are forced to admit that few countries have so many indications of cinnabar, as the table land of the Cordilleras from the 19° to the 22° of north latitude. In the intendancies
* To the west of the town of Cuenca, in the kingdom of Quito, there exists earthy grey manganese, which forms a bed in the freestone.
of Guanaxuato and Mexico, we find it almost wherever pits are dug between San Juan de la Chica and the town of San Felipe ; near Rincon del Centeno, in the environs of Celaya; and from Durasno, and Tierra Nueva to San Luis de la Paz, especially, near Chapin, Real de Pozos, San Rafael de los Lobos and" la Solędad. Sulphuretted mercury has been also discovered at Axuchitlan and Zapote *, near Chirangangueo, in the intendancy of Valladolid; at los Pregones near Tasco, in the district of mines of the Doctor; and in the valley of Tenochtitlan to the south of Gassayé in the road from Mexico to Pachuca. The works by which these different mineral depositories were proposed to be discovered, have been so frequently interrupted, and they have been conducted with so little zeal, and generally with so little intelligence, that it would be very imprudent to advance, as has been often done, that the mercury mines of New Spain are not worth the working. It appears, on the contrary, from the interesting information which we owe to the labours of M. Chovel, that the veins of San Juan de la Chica, as well as those of the Rincon del Centeno, and the Gigante, are 'very deserving of the attention of the Mexican miners. Was it to be expected that superficial works which were merely begun, should in the very first years, yield a 'net profit to the shareholders
*In the mines of San Ignacio del Zapote, where the cinnabar is constantly mixed with blue carbonated copper, while at Schemnitz and Poratich in Hungary the antimoniated grey copper (graugültigerz) contains 0.06 mercury. Klaproth, iv p. 65.
The mercury mines of New Spain are of very different formations. Some are found in beds in secondary earths; and others in veins which traverse trap porphyries. At Durasno, between Terra Nueva, and San Luis de la Paz, cinnabar mixed with a number of globules of native mercury, forms a horizontal bed (manto) which reposes on porphyry. This manto 'which has been pierced by pits of five or six metres * in depth, is covered with beds of sláte clay, which contains' fossil, wood, and coals. On examining the roof of the manto, we find from the surface, first a bed of slate clay (schieferthon) impregnated with nitrate of potash, and containing fragments of petrified "vegetables ; then a stråta of slate coal (schie'ferkohle) of a metre't in 'thickness; and lastly
slate "clay which immediately covers the cin'nabar minéral. From this 'mine there was drawn, eight years ago, in a very few months
* 16 or 19 feet. *+ 3.28 feet.