dollars, or £1,089,615 8s. sterling, or upwards of 365,000 lbs. troy of 12 ounces per lb. All the veins of Hungary and Transylvania put together, only yield 85,000 marks of silver, or 55,686 lbs. troy; so that the annual produce of the mines of Guanaxuato, is to all these latter combined, as 6 to 1. The mine of Valenciana in Guanaxuato, originally belonged to two single individuals, namely, the count de Valenciana, and M. Otero. It was not begun to be worked till 1760; and then by a solitary adventurer. In 1766, the works were already 262 feet in depth; and the expenses greatly exceeded the metallic value of its produce. In 1768 it began to pay, in proportion as the pit grew deeper. From 1771 to 1804, this mine never yielded less than £583,380 sterling annually to the two proprietors; and in some years, the nett profits clear of all expenses amounted to £250,000 sterling. The mine is now wrought to the depth of 1,685 feet. The present expenses of working the mine have been prodigiously augmented by the depth of the shafts and the prolongation of the galleries; and it will require a large capital to establish forcing pumps to extract the water. "In many instances," says a late writer, "it will be impossible to employ steam as the moving power, from the great scarcity of fuel."

An American traveller gives the following account of the mines of Guanaxuato: "The excavations extend from S.E. to N.W. 1,600 yards, and 800 yards in a S.W. direction. There are three parallels, or plains, worked on ramifications of the principal vein. The veta madre, or mother-vein, was here found not more than 22 feet wide, and without any ramification, from the surface of the soil to the depth of 557 feet. at this depth, it divides into three branches, the entire mass being from 165 to 195 feet thick. Of these three branches, not more than one is in general very productive. They have all the same angle (45°), but vary in thickness from 9 to 40 yards. Four shafts descend to these parallels. The first, called San Antonio, is of 744 feet perpendicular depth: the cost of this shaft was 396,000 dollars. The square shaft of Santo Christo, 492 feet deep, cost 95,000 dollars. The hexagon shaft of our Lady of Guadeloupe, 1,131 feet perpendicular depth, cost 700,000 dollars. San Josè, an octagon shaft of more than 1,800 feet perpendicular depth, and 300 feet in the direction of the veta madre, which is an angle of 45°, cost 1,200,000 dollars. To understand the necessity of sinking so many shafts of different depths, it may be necessary to explain, that in following the dip of the vein, which is first discovered on the surface, and is almost invariably an angle of 45°, the work is impeded after a certain depth by A shaft is then sunk, so as to intercept the vein at the termination of a gallery, in order to free the mine from water. The work is then continued until it becomes necessary to sink another shaft still deeper, to clear the lower galleries. At the termination of each shaft a great many parallel galleries branch out on ramifications of the mother-vein.

water.

"From these parallels a vast number of smaller galleries branch out, worked to a greater or less distance as the ore proved to be of good or bad quality; and many of them were pierced with a view of discovering other veins. Besides the shafts, there are two descents by steps, winding down to the last parallel. On leaving the house of the administrator, we were conducted to the first flight of steps: preceded by four men carrying torches, we descended to the first parallel, and stopped where four galleries branch off. Our torch-bearers were sent off to the extremity of these galleries, that we might form some idea of their extent in a straight

fine. They are both extensive and solid; the vaults are of porphyry, and the bottom of gray slate. In some places where the ore proved very rich, it has been taken from the sides and vaults, and the voids filled up with masonry and beams, worked in so as to form a firm support to the sides and roof. These galleries have been blasted out, and must have cost great labour, for the whole mountain is of porphyry to a great depth.

"The exterior is covered with a crust of breccia, which extends not more than four or five feet from the surface. The ore is for the most part extracted by drilling and blasting: sometimes, but very rarely, the wedge can be used. On our return, we plodded painfully up these stairs, which the cargadores (porters) ascend with ease, with a load of ten or fifteen arrobas on their shoulders. They are paid according to the quantity they bring up; and some of these men will ascend, as we are told, from the perpendicular depth of 500 yards, carrying the enormous weight of twenty-four arrobas (600 lbs.). In the court-yard into which we entered from the gallery, and where the workmen are searched, there was a large heap of ore, accumulated by each workman being obliged to bring a stone up in his hand every time he ascends, and throw it on this heap. There are about 1,000 workmen at present employed, and in the course of a week a large pile is formed. The product of this belongs to the mine, and forms a fund for contingent expenses. The matrices of these ores, which we had here a good opportunity of examining, are principally quartz, amethyst, and rock-crystal, horn-stone here and there, and a small portion of calcareous spar of a dark brown and of pearl colour. The metals are, pyrites or iron, arsenic, yellow copper, galena, gray and yellow blende, virgin gold and silver, sulphate of silver, both brittle and ductile, and rosicler, a rich silver ore of a bright rosy colour, which we did not see. This ore is so rare, that I could not meet with a specimen during my residence in Mexico. There are likewise veins with copper, lead, tin, cinnamon, antimony, and manganese; and the crystals of the carbonate of lime that are found in this mine, are very large and perfect.

"We next visited the principal shaft, San Josè, an octagon, the diameter 11 yards, and the perpendicular depth 600. This great work, which cost upwards of a million of dollars, is in some places blasted through solid rock, and in others walled up with hewn stone: the masonry is admirably well executed. The workmen threw bundles of lighted hay down the shaft, which blazed as they descended, and which we saw fall into the water, now not more than 250 yards from the summit, and rising every day. After failing in his attack on the city of Guanaxuato, Mina caused the machinery of the mine of Valenciana to be burnt, and the owners have not funds to renew it.

"From these mines we went to a shaft called Guadeloupe, where we found two malacates in operation. These machines are used to free mines from water, and to draw up the ore. A malacate is a drum of about ten feet in diameter, attached to a vertical spindle, a shaft of 15 feet long, which is shod with steel, and turns in steel sockets. Poles project at right angles from the shaft, to which the horses are harnessed. Two ropes are passed round the drum, and over pulleys supported by poles 12 feet high, and about 10 feet apart, leading to the well. As the drum turns, one rope descends, and the other is wound up, and raises a large skin full of ore, or buckets of water, by what the French call a chapelet. At the principal or octagonal shaft, eight malacates were kept constantly at work, night and day. Each malacate was moved by 12 horses, and drew up,

by a succession of buckets, 78 arrobas (975 quarts) every 9 or 10 minutes: 95,000 arrobas, or 31,800 cubic feet of water, might be raised by this means every 24 hours. It happened to be a sale day, and in the same court where the malacates were at work, we saw three or four hundred people collected; some exposing the ore to the best advantage, and others examining its quality. This mine is now worked by halves, the workmen receiving one-half of the profits, and the owners of the mine the other. The workmen were busily employed in arranging the pieces of ore in parallelograms, composed of small circular heaps of ore. They were very careful to place the richest pieces at top, and the fairest side in sight. When all was prepared, the salesman placed himself at the head of the first parallelogram; and the buyers, after examining the quality of the ore, whispered in his ear the price they were willing to give for it. When all had made their offers, he declared aloud the highest bid and the name of the purchaser. A note was made of the sale, and the whole party moved to the next parcel of ore, and so on, until the whole was disposed of. There are two sale days in the week, Wednesday and Saturday; and the weekly sales amount to between 5 and 6,000 dollars."

On the following day, our traveller set out to visit a hacienda de plata, belonging to the Conde de Valenciana, in the Canada de Marfil. "It is a spacious building, divided into three large courts; one for preparing the ores (patio pa. beneficiar,) and the others for horses and mules. The front is two stories high, very neatly built, and forms an excellent dwelling-house. From the house, we walked through the first court, where men and mules were treading out masses of mud, and entered a long range of buildings, where there were 35 mills at work grinding the ore. This hacienda, in prosperous times, works 70 mills. They resemble bark-mills. A circle of about 11 feet in diameter is paved with stones set up edgeways, and rubbed down to a smooth surface; in the centre of the circle an upright shaft moves in sockets. From this an axle projects, and passes through the centre of a millstone that rolls on its periphery: to the end of this axle the traces of the mules that turn it are attached. The first process is, separating the ore from the stones and refuse. Women are employed in this work. They throw aside the stones that have no ore, and with a hammer chip off small pieces of ore from those that have a little only on the surface. They perform this operation with great skill and great despatch. The ore is then placed on a thick iron plate, and is pounded by wooden pestles shod with iron, and moved by a horizontal shaft furnished with arms, like the movement of the pestles in our rice-mills. Two men, stationed one on each side, draw the ore from under the pestles upon plates that slope down from the top, and are perforated with holes so as to shift the ore as it falls on them. The large pieces are thrown back under the pestles. After the ore is broken into very small pieces, it is put into the mill, mixed with water, and ground to an impalpable powder. A small quantity of quicksilver is sometimes mixed with this mass while in the mill. From the mills, the ore, ground to a powder and moistened, is conveyed to the patio pa. beneficiar, the open paved court-yard; salt is then added in the proportion of about two pounds to every hundred weight of ore. If the mass, which is left untouched for several days, heats too rapidly, lime is added, which, the superintendant told us, cools it; if, on the contrary, it continues cold, magistral is mixed with it, in order to give it the

proper temperature. The magistral is a copper ore, or more properly a mixture of pyrites of copper and sulphuretted iron, which is roasted in a furnace, cooled gradually, and then reduced to a powder; a small quantity of salt is afterwards mixed with it. A small quantity of the powder magistral was put into my hand, and water poured upon it. The heat evolved was so great, that I was obliged to throw it away instantly; probably owing to the sulphuric acid acting upon the metals and disengag ing heat. The next operation is, to add quicksilver to the mass, commonly six times the quantity which it is supposed the mass contains of silver. This mixture of ore, ground to a fine powder and moistened, of quicksilver, muriate of soda, and the sulphates of iron and copper, is made into an amal gam, by being trodden by mules, which are driven round for hours together; or by men, who tread the mass with naked feet. We saw both in one mass; twelve mules were trotting round up to their fetlocks in the mixture; and in another, ten men were following each other, and treading up to their ankles in it. The superintendant examines the appearance of the amalgam from time to time, by taking up a little of it in a wooden bowl, and adds either salt, quicksilver, or magistral, as he finds necessary to complete the amalgamation. This process is repeated every other day until a perfect amalgam is made, when it is conveyed into large vats filled with water. In the centre of the vat there is an upright shaft, furnished with arms and turned by mules, so as to stir up the ore and mix it well with the water. It is left to subside, and the water is let off gently, carrying with is a portion of earth, and leaving the amalgam, which is precipitated; this process is repeated until the amalgamation is freed from all extraneous matter. It is then moulded into triangles, which are placed under stout iron recipients of a bell shape, and the mercury is separated by heat, leaving the silver with a small portion of copper, not enough for the usual alloy.

"One of the grinding-mills, in which quicksilver had been added to the mass, was emptied and cleaned in my presence, in order to get out the amalgam, which is precipitated, and lodges in the interstices of the stones with which these mills are paved. After the floating mass was removed, the stones were scraped, and the crevices emptied. The contents were put into a wooden bowl and washed. This amalgam, besides silver, contains a large portion of gold. The ore of the mine of Valenciana contains some gold, which unites with the quicksilver, and this amalgam being so much heavier, is more quickly precipitated. The bars of silver made from these cleanings contain always the largest portion of gold, and are kept apart."

Mines of Zacatecas.] The mines of Zacatecas produce annually from 2,500 to 3,000 bars of silver, at 134 marks each, or from 2,19,866 to 268,839 lbs. troy. The value of this annual produce is from 2,847,000 to 3,417,000 dollars, or from £640,687 to £768,825 sterling; but the mineral produce of the mines of Zacatecas is not very constant. In 1770, their produce scarcely furnished 50,000 marks of silver annually to the mint at Mexico, or 32,815 lbs. troy; in a short time after, by the activity of Laborde, a French miner, their produce rose to 500,000 marks, or 328,150 lbs. troy annually, value 4,250,000 dollars, or £956,250 sterling. The mine of Fresnillo, in this intendancy, is very feebly wrought; and would produce much more, if wrought with vigour and skill. According to Sonnenshmidt, the rock is there traversed by innumerable veins, rich in grey and green muriated silver. The mines of Sombrerete, in this intendancy, are celebrated from the immense riches of the vein of the vcta