THE middle of the seventeenth century saw the profession thus far on its way--certain objective features of disease were known, the art of careful observation had been cultivated, many empirical remedies had been discovered, the coarser structure of man's body had been well worked out, and a good beginning had been made in the knowledge of how the machinery worked--nothing more.

What disease really was, where it was, how it was caused, had not even begun to be discussed intelligently.
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.