Quinine using the bark of the cinchona tree for that purpose. While its effect in treating malaria (and malaria-induced shivering) was unrelated to its effect in controlling shivering from rigors, it was a successful medicine against malaria. At the first opportunity, Salumbrino sent a small quantity to Rome for testing as a malaria treatment. In the years that followed, cinchona bark, known as Jesuit's bark or Peruvian bark, became one of the most valuable commodities shipped from Peru to Europe. When King Charles II was cured of malaria at the end of the 17th Century with quinine, it became popular in
Jesuit's bark of the long list of brochures defending its use and the only independent article on this bark which has been issued by a Jesuit. The two Genoese, Girolamo Bardi, a priest, and Sebastiano Baldo, a physician, who were among the pioneer advocates of the plant, were intimate with the cardinal, and Baldo prefixed to his principal work a letter from de Lugo, dated 1659, on cinchona, which shows that the cardinal even when seventy-seven years old was still active in its behalf. Circumstances created a suitable opportunity for disseminating the bark from Rome throughout Europe by means of the Jesuits.