Many years elapsed before much addition was made to the processes described by Agricola. In the year 1566, Pedro Fernandes de Velasco introduced a method of extracting gold and silver from their ores in Mexico and Peru by means of quicksilver. But I have never seen a description of his process. Alonzo Barba claims for himself, and seemingly with justice, the method of amalgamating the ores of gold and silver by boiling. Barba was a Spanish priest, who lived about the year 1609, at Tarabuco, a market-town in the province of Charcso, eight miles from Plata, in South America. In the year 1615 he was curate at Tiaguacano, in the Province of Pacayes, and in 1617, he lived at Lepas in Peru. He is said to have been a native of Lepe, a small township in Andalusia, and had for many years the living of the church of St. Bernard at Potosi. His work on the amalgamation of gold and silver ores appeared at Madrid in the year 1640, in quarto.[174] In the year 1629 a new edition of it appeared with an appendix, under the title of “Trattado de las Antiquas Minas de España de Alonzo Carillo Lasso.” The English minister at the Court of Madrid, the Earl of Sandwich, published the first part of it in an English translation at London, in 1674, under the title of “The First Book of the Art of Metals, in which is declared the manner of their generation, and the concomitants of them, written in Spanish by Albaro Alonzo Barba. By E. Earl of Sandwich.” [174] It is entitled, “El Arte de los Metales, en que se ensena el verdadero beneficio de los de oro y plata por azoque,” &c.