Starting in Egypt, alchemists were the predecessor to the modern chemist. Though they are largely discredited by the scientific community due to the fact that many included religion and the occult to 'fill in the blanks', they made great strides in scientific research, sometimes by accident (i.e. discovery of gunpowder trying to find immortality). After egypt, the next earliest is probably in China, where gunpowder was discovered. Many famous physicists were alchemistds, such as Isaac Newton. Today there are still alchemists, though they practice (usually) practical alchemy. This is the practice of alchemy that actually has a purpose, and the study and reproducion o=f ancient alchemical experiments, usually involving finding out both how the experiments were beleived to work by ancient alchemists, and how they work in terms of current chemists, and whether there is any connection.
One practical alchemy experiment is the extraction of salt from rosemary (popular experiment by some alchemist on the web), while other alchemy experiments include the accidental discovery of gunpowder in China.