An empirical discovery of the first importance marks the middle of the century. The story of cinchona is of special interest, as it was the first great specific in disease to be discovered. In 1638, the wife of the Viceroy of Peru, the Countess of Chinchon, lay sick of an intermittent fever in the Palace of Lima. A friend of her husband's, who had become acquainted with the virtues, in fever, of the bark of a certain tree, sent a parcel of it to the Viceroy, and the remedy administered by her physician, Don Juan del Vego, rapidly effected a cure. In 1640, the Countess returned to Spain, bringing with her a supply of quina bark, which thus became known in Europe as "the Countess's Powder" (pulvis Comitissae). A little later, her doctor followed, bringing additional quantities. Later in the century, the Jesuit Fathers sent parcels of the bark to Rome, whence it was distributed to the priests of the community and used for the cure of ague; hence the name of "Jesuits' bark." Its value was early recognized by Sydenham and by Locke. At first there was a great deal of opposition, and the Protestants did not like it because of its introduction by the Jesuits. The famous quack, Robert Talbor, sold the secret of preparing quinquina to Louis XIV in 1679 for two thousand louis d'or, a pension and a title. That the profession was divided in opinion on the subject was probably due to sophistication, or to the importation of other and inert barks. It was well into the eighteenth century before its virtues were universally acknowledged. The tree itself was not described until 1738, and Linnaeus established the genus "Chinchona" in honor of the Countess.(1) (1) Clements R. Markham: Peruvian Bark, John Murray, London, 1880; Memoir of the Lady Anna di Osoria, Countess of Chinchona and Vice-Queen of Peru, 1874. A step in advance followed the objective study of the changes wrought in the body by disease. To a few of these the anatomists had already called attention. Vesalius, always keen in his description of aberrations from the normal, was one of the first to describe internal aneurysm. The truth is, even the best of men had little or no appreciation of the importance of the study of these changes. Sydenham scoffs at the value of post-mortems.