The common perception of alchemists is that they were pseudo-scientists, who attempted to turn lead into gold, believing that the universe was composed of the four elements of earth, water, fire, air, and spent most of their time concocting miraculous remedies, poisons, and magic potions.
Most alchemist were well-meaning and intelligent men and distinguished scientists, such as Isaac Newton and Robert Boyle. These innovators attempted to explore the nature of chemical substances and processes. They had to rely on experimentation, traditional know-how, rules of thumb and speculative thought in their attempts to uncover the mysteries of the physical universe.
At the same time, it was clear to the alchemists that "something" was generally being conserved in chemical processes, even in the most dramatic changes of physical state and appearance; that is, that substances contained some "principles" that could be hidden under many outer forms, and revealed by proper manipulation. Throughout the history of the discipline, alchemists struggled to understand the nature of these principles, and find some order and sense in the results of their chemical experiments