The annual produce of the mines of Buenos Ayres is estimated at 882,000_l._, including those of Caylloma in Arequipa, which are said to be attached to the government of La Plata. This produce is nearly all silver. The quantity that has annually paid the fifth being in fine gold 2200 marcs, and in fine silver 414,000 marcs, or 4,212,400 piastres. Its contraband trade in these metals has also been estimated at 67,000 marcs, most of which passes to Europe by the Rio de la Plata, while in Peru, by the Amazons and the South Sea, the same unlawful trade carries away 100,000 marcs. The trade of Buenos Ayres consists in these metals, and in exports of salt beef, tallow, fine furs, sea wolf-skins, wool, sheep-skins, flour, oil, copper, hides, &c.; to the interior provinces of Peru it sends Paraguay tea, swan skins, negro slaves, thread, &c., in exchange for sugar, cacao, cinnamon, rice, indigo, cotton, oil, pimento, wax, baize, woollen goods, quicksilver, &c. From Europe La Plata receives linens, woollens, silks, cottons, hats, iron, &c., and the imports may be estimated, in average years, at 758,400_l._, whilst its exports amount, in agricultural produce, to 434,000_l._, and in gold and silver to 1,183,400_l._, thus forming a total of 1,617,400_l._ sterling. It formerly remitted 700,000 piastres, at 4_s._ 4_d._ each, to the royal coffers: but since the late struggle its expences have been so great in maintaining the insurgent cause, that it can hardly defray them; especially since the viceroy of Peru has taken possession of the richest mines for the king. _Capital._--The capital of this viceroyalty is the city of BUENOS AYRES, containing a population of sixty thousand souls, or, according to Estalla, of forty thousand, of whom the greater part are creoles. This city is situated in 34° 35' south latitude and 57° 24' west longitude, on the south side of the Rio de la Plata, adjoining to a small river, from which the plain it is built on, gently ascends. It was founded in 1535 by Don Pedro de Mendoza, who gave it the name of Buenos Ayres, on account of its fine climate, but was abandoned soon after, and not rebuilt until 1582, after which it speedily increased and was erected into a bishopric in 1620, and into the capital in 1776. Buenos Ayres is well fortified, and its streets are straight, handsome, and clean, being paved on each side. The principal square is very large, and contains the residence of the governor, and the houses are built of brick or chalk, consisting generally of two stories, with a tiled roof. The cathedral is a spacious and elegant structure, and there is a church appropriated for the Indians, with several convents, chapels, &c.