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in an alarming proportion, when the norks have reached a perpendicular depth of 500 metres". The piercing and walling of the three old draught-pits cost the count de Walenciana nearly six millions of francs, viz.

Piastres The square pit of San Antonio or

tiro viejo, 227 metres of perpendicular depth, and four baritels a chevaux, 396,000

The square pit of Santo Christo de Burgos 150 metres in depth and tno baritels a chevaux • 95,000

The hexagonal pit of Nuestra Señora de Guadalupe (tiro nuevo) 345 metres in perpendicular depth and six baritels a chevaux 700,000

Expence of the three pits. 1,191,000

Within these twelve years they have begun to dig in the solid rock, in the roof of the vein a new draught-pit (tiro general) which will have the enormous perpendicular depth of 514 metres t, terminating at the actual bottom of the mine or at the planes of San Bernardo. This pit which will be in the centre of the works, will considerably diminish the number of the 980 miners (tenateros) employed as beasts of burden to carry the minerals to the upper places of assemblage. The tiro general which will cost more than a million of piastres * is octagonal and contains 26". 8 of circumferencef. Its walling is most beautiful. It is believed that they will reach the vein in 1815, although in the month of September 1803 the depth was not yet more than 184 metres f. The piercing of this pit is one of the greatest and boldest undertakings to be found in the history of mines. It may be questioned, however, whether for the sake of diminishing the expences of carriage and draught, it was expedient to recur to a remedy which is at once slow, expensive, and uncertain.

* 1640 feet. Trans.

+ 1685 feet. Trans.

I reduce the varas mericanas on the principle that a vars is equal to 0° 839 or a toise = 2. 332 paras mericanar * {218,767 Sterling.

(See Vol. ii. p. 165). In that country they consider the mines of Valenciana the deepest ever dug by man. At the period when I measured the planes of San Bernardo, the mine of Berchert Glück, at Freiberg in Saxony had reached 447 metres of perpendicular depth (1465 feet Trans.) It is believed that in the sixteenth century the works of the Saxon mines on the vein Alter Thurmhof went as far as 545 feet in depth (1787 feet. Trans.). Author. The expences of working the mine of Valenciana have been on an average annually: Piastres From 1787 to 1791 - - - - 410,000* From 1794 to 1802 - - - - 890,000 + Although the expences are doubled, the profits of the share-holders have remained nearly the same. The following table contains an exact state of the mine for the last nine

+ 87 feet. Trans.

£ 603 feet. Trans.


* e89,694. Sterling. Trans.

+ é194,708 Sterling.

Estado que manifiesta el valor de los frutos que ha producido la mina de Valenciana, costa de sus memorias y hiquido producto, a favor de sus duenos; lo presentó Don Joseph Antonio del Maso al Ercellentissimo Senior Virey de Nueva Espana Don Joseph de Yturigarray, el 3 de Julio 1803. (M.S.)

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PERIODS. Total of e- _ - the 9 1794 | 1795 1796 1797 1798 1799 1800 1801 1802 years' Produce of the sale of | o: 128.2042-1696640. 1315424; 2128439-1724437] 1584,393, 1480933|-1394.338-1229631||13835380 na (in ity tres). Expences - - of working 799328 815817; 832847 878789-890735. 915488 977314|| 991981| 944809 8046063 (in piastres) a lo --- Net profit | - || -divided a- - - --- o -- mong the - - sharehold- 48.2713| 8808 so * * * * 5791.317 rs (in pias- - ---|-- - - - - - -tres). p o - - - - - - -t. o - - o - o -- - - ... - o o - - - - o - o o


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The result of this table is, that the net profit of the share-holders, has been latterly at an average of 640,000 piastres per annum.” In 1802 circumstances were extremely unfavourable. The greater part of the minerals were very poor, and their extraction attended with great expence; and besides this, the produce was sold at very low prices, because the want of mercury impeded the amalgamation, and all the mines were incumbered with minerals. The year 1803 promised greater advantages to the proprietors, and they reckoned on a nett profit of more than half a million of piastrest. I saw them sell weekly at Valenciana, silver minerals to the amount of more than 27,000 piastres: The expences amounted to 17,000. At Rayas, the profit of the proprietor was greater, though the produce was less; for this mine furnished more than 15,000 piastres of minerals weekly, while the expence of working only amounted to 4000 piastres. This was the effect of the richness of the minerals, their concentration in the vein, the inconsiderable depth of the mine, and consequently a less expensive draught.

* Above 3,360,000 livres tournois (<140,011 sterling. Trans.) The profit distributed annually among the share-" holders of the district of Freiberg, only amounts to 250,000 livres (<10,417 Sterling. Trass.)

+ £109,383 Sterling. Trans.

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