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Alexandro Bustamente, was courageous enough to undertake a level near Moran; but he died before completing this great work, which is 7715 feet in length from its mouth to the point where it crosses the vein de la Biscaina. The direction of this vein is hor. 6; and its inclination is 85° to the south its extent is from 13 to 19 feet. The direction of the porphyry of this district is generally hor. 7-8, with an inclination of 60° to the northeast, particularly in the road from Pachuca to Real del Monte. The level is at first cut through the solid rock (querschlagsweise) in a direction of hor. 7, towards the west; but further on it takes its way over three different veins, hor. 11-12, of which one alone, the veta de le Soledad*, has furnished a sufficiency of silver ores to pay all the expenses of the undertaking. The level was only finished in 1762, by Don Pedro Tereros, the partner of Bustamente. The former, known by the title of Count de Regla as one of the richest men of his age, had already drawn, in 1774, a net profit of more than 1,041,750/. from the mine of Biscaina. Besides the two ships of war which he presented to King Charles the Third, one of them of 120 guns, he

*It is believed that this vein is the same with that which M. D'Eluyhar began to work in the pit of Cambrera, at Moran. It appeared to me, however, that the veta de Cabrera is rather the same with that of Santa Brigida, and that its principal wealth is to be found in following it towards the mine of Jesus.

lent 208,350. sterling to the Court of Madrid, which have never yet been repaid him. He erected the great works of Regla at an expense of 416,7007. sterling; and he purchased estates of an immense extent, and left a fortune to his children, which has only been equalled in Mexico by that of the Count de la Valenciana.

The level of Moran traverses the vein of La Biscaina, in the San Ramon shaft, at a depth of 115 fathoms, below the level of the surface, on which the whims are placed. The profit of the proprietor has been annually diminishing since 1774. In place of driving levels for trial, to discover the vein on a great extent, they continued their sinking to a depth of nearly 53 fathoms below the level. At that depth the vein preserved its great wealth in sulphuret of silver mixed with native silver; but the abundance of water increased to such a degree that 28 whims, each of which required more than 40 horses, were not sufficient to draw it off. In 1783, the weekly

After the death of

expense amounted to 18757. the old Count de Regla, the works were suspended till 1791, when they ventured to re-establish all the whims. The expense of these machines, which drew up the water not by means of pumps but by bags suspended by ropes, then amounted to more than 31,2527. per annum. At length they reached the deepest point of the mine, which according to my measurements is only 1064 feet above

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the level of the lake of Zumpango; but the ores which they extracted did not compensate the expense of the process, and the mine was again abandoned in 1801..

It is surprising that they never thought of substituting for this wretched plan of drawing off the water by bags, proper pump apparatus put in motion by horse whims, by hydraulic wheels, or by machines moved by a column of water (colonne d'eau). A level begun at Pachuca, or lower down towards Gazave in the valley of Mexico, would have exhausted the mine of Biscaina at the pit of San Ramon, for a depth of 202 fathoms. The same object could be attained at less expense by following the project of M. D'Elhuyar, in placing the mouth of a new level near Omitlan, in the road which leads from Moran to the place of amalgamation at Regla. This last level, before reaching 12,466 feet in length, would cut the vein of Biscaina.

The very wise plan which the Count de Regla at present follows is, to leave off the clearing of the old works, and to investigate the mineral repository, in points where it has never yet been worked (in unverfahrenem felde). In studying at Real del Monte the surface and undulations of the ground, we observe that the vein of Biscaina has furnished for three centuries its greatest riches from a single spot, that is to say, from a natural hollow (enfoncement) contained between the shafts

of Dolores, Joya, San Cayetano, Santa Teresa, and Guadalupe. The shaft from which the greatest quantity of silver ores has been extracted is that of Santa Teresa. To the east and west of this central point the vein is contracted for a distance of more than 1300 feet. It preserves its primitive direction, but becomes destitute of metals, and reduced to an almost imperceptible vein. For a long time it was believed that the vein of Biscaina was insensibly lost in the rock; but they discovered in 1798 very rich metals, at a distance of more than 1640 feet, to the east and west of the centre of the old works. They then sunk the shafts San Ramon and San Pedro, and discovered that the vein resumed its old power, and that an immense field was opened to new undertakings. When I visited the mines in the month of May 1803, the San Ramon shaft was then only 16 fathoms in depth; and it will be nearly 131 fathoms to the bottom of the level of Moran, which is itself still distant 147 feet from the point which corresponds to the intersection of the new shaft, and the roof of the level. In its present state, the mine of the Count de Regla annually yields more than from 30,000 to 40,000lbs. troy of silver.

The vein of Biscaina contains in the points of the principal mines, milk-quartz, which frequently passes into splintery hornstone, amethyst, carbonate of lime, a little sulphate of barytes, sulphuret of silver mixed with native silver, and sometimes pris

matic black silver (sprödglaserz), deep-red silver, galena, and iron and copper pyrites. The same silver ores are found near the surface of the ground in a state of decomposition, and mixed with oxide of iron, like the pacos of Peru. Near the San Pedro shaft, the pyrites are sometimes richer in silver than the sulphuret of silver.

The mines of Moran, formerly of great celebrity, have been abandoned for 40 years, on account of the abundance of water which could not be drawn off. In this district of mines, which is in the vicinity of that of Real del Monte, near the mouth of the great level of Biscaina, there was placed in 1801 a machine à colonne d'eau, of which the cylinder is 10.23 inches in height, and 6.29 in diameter. This machine, the first of the kind ever constructed in America, is much superior to those of the mines of Hungary. It was executed agreeably to the calculations and plans of M. del Rio, professor of mineralogy in Mexico, who has visited the most celebrated mines of Europe, and who possesses at once the most solid and the most various acquirements. The merit of the execution is due to M. Lachausée, a Brabant artist of great talents, who has also fitted up for the school of mines of Mexico a very remarkable collection of models, for the use of students of mechanics and hydrodynamics. It is to be regretted that this fine machine, in which the regulator of the suckers is put in motion by a particular mechanism, was placed in a situation