work, which enraged the Indians in Backhouse's service, and a quarrel ensued, ending in the massacre of Backhouse and all his party. Those who were out collecting bark, on discovering what had happened, fled to Colonel Bologenesi; but in their retreat, while fording a river, the Chunchos poured in a volley of arrows amongst them, and killed forty of their number. Bologenesi then collected a military force and advanced into the forests, where he suffered great hardships, fighting with the Chunchos all day, and harassed by alarms during the night. He, however, collected a thousand quintals of bark, at a cost of fifty lives and three hundred thousand dollars. During this expedition indications were met with of the ancient gold-washings. It will thus be seen that fevers and perilous roads are not the only dangers to be apprehended in a search for chinchona-plants. Lastly, and extending for a distance of one hundred and eighty miles, from Marcapata to the frontier of Bolivia, is the watershed along that part of the eastern Andes known as the Snowy Range of Caravaya, where the numerous streams take their rise which unite to form the Ynambari. The Madre de Dios, Marcapata, and Ynambari are thus the three great sources of the Purus. The tributaries of the latter drain the province of Caravaya. The first mention of this region is to be found in the pages of the old Inca historian, Garcilasso de la Vega, who says that "the richest gold-mines in Peru are those of Collahuaya, which the Spaniards call Caravaya, whence they obtain much very fine gold of twenty-four carats, and they still get some, but not in such abundance."[291] The Jesuit Acosta also mentions "the famous gold of Caravaya in Peru."[292] After the final overthrow of the younger Almagro in the battle of Chupas in 1542, some of his followers crossed the snowy range, and descended into the great tropical forests of Caravaya,[293] where they discovered rivers, the sands of which were full of gold. On the banks of these rivers they built the towns of Sandia, San Gavan, and San Juan del Oro; large sums in gold were sent home to Spain, and the last-named settlement received the title of a royal city from Charles V. In 1553 these settlers received a pardon from the Viceroy Don Antonio de Mendoza, in consideration of the gold they sent home to the Emperor. It is said that they sent him a nugget weighing four arrobas, in the shape of a bullock's head; and that afterwards another nugget, in the shape of a bullock's tongue, was sent to Philip II., but that the ship which carried it was lost at sea. Eventually the wild Chuncho Indians of the Sirineyri tribe fell upon the gold-washers, and overpowered them. In the following century certain mulattos occupied the gold-washings in Caravaya, and the king, as a reward for their labours in extracting treasure, offered to comply with any request they might make. The mulattos asked to be called Señores, and for the privilege of entering