116
AMERICAN MINES.
CHAP. XXI.
nificant that an error cannot exist to an extentwhich would make a difference in the whole cal-culation of two per cent.
Although there was much fluctuation in theproduce of the American mines during the seven-teenth century, yet upon the whole there was anincrease, though not a large one. The mines inthe district of Potosi in Peru had declined to agreat extent. In the first fifteen years of the cen-tury they had yielded one million six hundred andseventy thousand three hundred and forty-fourpiastres, or about three hundred and fifty thousandpounds; and in the last fifteen years, from 1685 to1699, both years inclusive, the average amountsto no more than five hundred and fifty-nine thou-sand nine hundred and forty-three piastres, orabout one hundred and sixteen thousand six hun-dred and sixty pounds. At the first discovery ofthat mass of mineral wealth, the Spanish con-querors exercised the most unlimited power overthe natives. They were driven to the severe labourof the mines in a cold and inhospitable climate,where subsistence was difficult to be obtained ; andthe change from the deep and warm and fruitfulvalleys where they had passed their time in tran-quillity and abundance swept them away in greatnumbers. The interference of the government ofSpain , which sent commissioners and strict ordersto mitigate the lot of the natives, was ineffectual:the rude adventurers who had conquered the