Early history indicates that the practice of medicine was relatively well developed in Egypt and India before it had reached even a primitive stage in the temperate zone. The primeval method of treating diseases was, however, that known as empiricism. A certain drug or method would be used in a certain disease because it had seemed to do good in similar cases. Nearly all advances made in diagnostic methods seem to have been followed very soon by a corresponding advance in therapeutics. A great stimulus to the study of tropical medicine was the discovery of land in the tropics of the western hemisphere. This was followed by the migrations of many adventurous, courageous peoples who settled in the wide-spread primitive regions of the hot countries. Many European colonies were established and the people began to report their experiences. Cinchona was made known in 1640 as a treatment for malaria yet the parasite of this disease was not established as a fact until 1880 by Laveran.