of livres tournois *. Ulloa has communicated some historical information respecting this mining operation, which has had the most powerful effect on the commerce and price of commodities of Europe; but he could only collect very incomplete materials, founding his calculations on the consumption of mercury in the amalgamation works. I am enabled to publish from official papers, year after year, between 1556 and 1789, the value of the duties (derechos de reales) paid into the provincial treasury of Potosi, on the silver given into the mint. As the proportion which has existed at different periods between these duties and the value of the silver extracted from the mines, is known, we may deduce from the three following tables the annual produce in piastres.

* 234,693,840 Sterling. Trans.

ROYAL DUTIES (DERECHOS REALES)

Paid on the silver extracted from the Cerro de Potosi

TABLE 1.

First period, from 1st January, 1556, to 31st December, 1578, during which the fifth alone was paid.

Fifth.

Fifth.

Fitth.

Years. Piastres. Reals. Years. Piastres. Reals. Years. Piastres. |Reals.

TABLE II.

econd period from the 1st January, 1579, to the 19th July, 1736, during which at first one and a half per cent. de cobos was paid, and afterwards the fifth of the remaining 98 piastres 4 reals.

579 1,091,025 3 1613 1,200,947 6 1647 891,287 0 580 1,189,323 1 1614 1,269,692 7 1648 1,123,932 2 581 1,276,872 6 16151,354,412 3 1649 1,067,376-1 582 1,362,855 7 1616 1,257,599 0 1650 5831,221,428 3 16171,071,932 4 1651 5841,215,558 1 16181,061,264 2 1652 585 1,526,455 1 16191,108,744 6 1653 5861,456,958 0 1620 1,069,599 3 1654 587 1,226,328 0 1621 1,099,244 1 1655 5881,441,657 0 1622 1,093,201 41656 1623 1,083,641 7 1657 1624 1,086,999 0 1658

589 1,578,823 7

590 1,422,576 1
5911,562,522 2 1625 1,024,794 3 1659
592 1,578,449 6 1626 1,033,868 7 1660
593 1,589,662 1 1627 1,068,612 3 1661
594 1,403,555 7 16281,172,352 3 1662
5951,557,221 3 1629 972,807 0 1663
5961,468,182 5 1630 962,250 4 1664
5971,355,954 6 16311,067,001 6 1665
598 1,310,911 7 1632 964,370 6 1665
599 1,339,685 2 1633 1,003,756 0 1667
600 1,299,028 5 1634 984,414 6 1668
601 1,477,489 7 1635 946,781 0 1669
6021,519,152 7 1636 1,424,758 6 1670
603 1,178,697 6 1637 1,197,572 4 1671
6041,326,231 6 1638 1,174,393 0 1672
6051,532,646 6 1639 1,128,738 2 1673
6061,434,981 5 1640 978,483 2 1674

917,8457 757,418 6 796,244 2 759,904 5 835,109 4 754,784 1 804,071 0 933,441 4

877,862 1

799,609 1 652,728 4 623,250 7 638,167 3 579,126 7 605,450 3 655,557 0 675,729 4 708,879 2 691,169 0 624,126 4 554,614 0 667,992 3 624,037 6 676,811 0

673,694 7

607 1,414,660 1 1641 940,867 1 1675

567,827 5

608 1,200,488 5 1642

905,797 6 1676

514,530 4

609 1,132,680 4 1643

924,659 0 1677

550,099 3

6101,139,725 4 1644

871,174 3 1678

653,067 1

6116,299,052 2 1645

908,414 4 1679

622,979 5

6121,329,701 71646

840,982 0 1680

629,270 0

SEQUEL OF TABLE II.

One and a hal
per cent, and tifth.

One and a half,
per cent. and fifth.

One and a bali per cent.and fifth.

Years.

Piastres. Reals. Years. Piastres. Reals Years. Piastres. Reals.

1681685,791 0 1700 405,492 5 1719 283,593 3 1682 659,341 0 1701 338,572 4 1720231,256 7 1683 731,599 6 1702372,447 1 1721229,002 0 1684 719,082 0 1703 360,114 6 1722 228,208 5 1685 655,256 0 1704 333,702 0 1723 214,740 3 1686586,835 7 1705319,264 7 1724245,793 4 1687 645,318 1 1706354,600 1 1725223,083 3 1688 646,077 3 1707 364,415 0 1726274,416 1 1689 647,189 0 1708374,183 6 1727286,328 3 1690 673,097 1 1709334,080 4 1728 220,698 1 1691 593,976 1 1710309,008 1 1729 360,414 7 1692 424,761 7 1711246,147 1 1730303,361 6| 1693570,870 2 1712204,931 6 1731 293,497 3 1694546,928 3 1713279,913 11732308,137 3 1695 557,145 1 1714265,087 1 1733 504,768|| 3| 1696 500,965 3 1715 228,224 01734 273,084 5 1697 471,686 4 1716 239,287 01735 271,621 6

1698 434,772 1 1717356,804 1 1736 149,567 0 1699434,287 0 1718 322,251 1

Total of the 158 years, 129,417,273 piastres.

TABLE III.

Third period between the 20th July, 1736, and the 31st December, 1789, during which one and a half per cent. and the half of the fifth were paid, or 11 piastres, 3 reals per 100 piastres.

Years. Piastres. Reals. Years. Piastres. Reals. Years. Piastres. Reals,

1736 85,410 2 1754244,148 2 1772298,983 14 1737 183,704 3 1755221,872 4 1773306,925 3 1738159,252 7 1756249,513 7 1774,317,703 4 1739 183,295 6 1757 244,760 6 1775332,329 44 1740 170,229 4 1758 262,835 4 1776346,319 5 1741 179,573 6 1759 263,701 6 1777390,676 5 1742 161,976 0 1760272,059 1 1778351,994 6 1743 166,131 11761261,580 7 1779,348,035 4 1744 155,926 3 1762257,201 7 1780 400,062 1₫ 1745163,140 0 1763 279,646 6 1781323,109 2 1746 178,080 6 1764263,092 12 1782350,199 2 1747 184,156 5 1765 281,985 5 1783 400,238 31 1748 197,022 71766282,405 0 1784371,362 2 1749215,283 3 1767 303,650 6 1785351,777 7 1750 233,677 5 1768 306,674 7 1786532,507 1 1751 238,502 31769291,075 3 1787 390,836 7 1752 227,133 5 1770 292,203 3 1788380,600 1 1753 244,888 141771|307,765| 34 |1789|335,468 6

Total of the 54 years 14,542,684 piastres.