In the seventeenth century, however, at least one discovery in therapeutics was made that has been an inestimable boon to humanity ever since.

This was the introduction of cinchona bark (from which quinine is obtained) in 1640.

But this century was productive of many medical SYSTEMS, and could boast of many great names among the medical profession, and, on the whole, made considerably more progress than the preceding century.
Of the founders of medical systems, one of the most widely known is Jan Baptista van Helmont (1578-1644), an eccentric genius who constructed a system of medicine of his own and for a time exerted considerable influence.

But in the end his system was destined to pass out of existence, not very long after the death of its author.

Van Helmont was not only a physician, but was master of all the other branches of learning of the time, taking up the study of medicine and chemistry as an after-thought, but devoting himself to them with the greatest enthusiasm once he had begun his investigations.