In 1619 another great silver find was made, this time near Lake Titicaca. A few years later civil war broke out among the Potosi miners caused by the rancorous greed of the speculators who worked the mines under contract. Official authority could do little to suppress the bloody encounters, and the factions were only reconciled after three years of fighting. The discovery, in 1657, of another very rich silver mine near the lake brought on desperate fights among the miners who flocked to the place. The chief contractor enraged the other Spaniards by his exactions, and the situation became so serious that in 1665 the viceroy went in person and summarily tried and executed forty-two persons, among them the contractor's own brother. For one hundred and fifty years the Spaniards had failed to find gold deposits equal to those from which the Incas had drawn the fabulous treasures that paid Atahuallpa's ransom, but about the end of the seventeenth century rich placers were discovered in the mountains east of Lake Titicaca. The town of Sorata soon rivalled Potosi in opulence. Shortly thereafter other great gold deposits were found on the eastern slope of the inner Andes by adventurous Brazilians who had made their way across the continent to the eastern headwaters of the Madeira and ascended the Beni River as far as the escarpment of the great plateau. The news of the discovery brought a crowd of Spanish miners from Chile, and as the placers were rich and Indian labour abounded, fortunes were rapidly accumulated. The gold was sold in annual fairs which continue to be held to this day, but as is always the case in gold washings the first results were the best. The region is too difficult of access for quartz mining, and the production rapidly fell off. Activity in that part of Bolivia ceased in the eighteenth century and only a few Indians continued to wash a little gold in the remoter streams. In 1781 Sorata was destroyed and the gold country virtually abandoned. CHAPTER II THE COLONIAL SYSTEM AND TUPAC'S REVOLT