Guanajuato, when it yielded its six millions a year of silver, besides a fair supply of gold, was one of the most important States in the republic. With every successful speculation, new adventurers were found to invest their capital in resuming the working of abandoned mines, until at last men have become bold enough to undertake, for the third time, the draining of the great shaft of the Valenciana, so famous in the last century. When I was last in Mexico that undertaking was reported to have been accomplished. This mine is on a more magnificent scale than even the Real del Monte. Its central shaft alone cost a million of dollars; and though steam power can not be used, yet it is so dry that horse windlasses can keep it clear of water. Its abandonment in every instance has been in consequence of some insurrectionary chief setting the works of the mine on fire, and not from any deficiency in its product of silver. When I was in Mexico, so little progress had been made in restoring the mine that it was not thought worth visiting. But the most sanguine hopes were entertained that it would again be as productive as in the times when its abundant riches secured for its owner the title of Marquis of Valenciana, though he had worked with his own hands on the shaft which afterward yielded him its millions. THE MINE OF LOS RAYAS. Second in importance among the old mines of Guanajuato is _Los Rayas_. Its history presents a new feature in the mining system of Mexico, not before mentioned, but which is important to a right understanding of the operation of the mining code. The right of discovery gives title to two hundred _varas_ along the mine, and to two hundred _varas_ (about 500 feet) in depth. The consequence of this limitation is, that when a very rich claim is made, there immediately springs up a contest to get below it, and to cut off the lucky discoverer from the lower part of his expected fortune, and he has no means of avoiding such a result but by driving his shaft downward until he reaches a point below his first two hundred _varas_, which entitles him to claim another section downward. This principle is strikingly illustrated in the case of the famous mine of the priest Flores at Cuatorce, which he blasphemously named "the Purse of God the Father,"[77] where there are marks of divers attempts being made to undermine him, though without success. But the case is a different one when the _bonanza_ is upon a high ridge, and it can be undermined by drifting in from a lower level. Then commences a lively contest to determine who can dig the fastest, and make the most rapid progress in this contest of mining and countermining. The Marquis de los Rayas owes his title and his princely fortune of $11,000,000 to a successful contest of this character. The Santa Amita was in _bonanza_, yielding an ore so pregnant with gold that the crude mass often sold for its weight in silver. DEEP MINING.