He worked during the years just after Paracelsus and iatrochemistry, and is ...Van Helmont is remembered today largely for his ideas on spontaneous ...For Van Helmont, air and water were the two primitive elements. Fire he explicitly denied to be an element, and earth is not one because it can be reduced to water.

practical period-was traced back during the prehistoric times when primitive men were pre occupied for survival

-marked the use of fire& production of metals, pottery,wine making, etc

-was based from the practical experience of primitive men w/o reference from the underlying principles of science

-to prevent sickness, they became expert in making medicine w/ the use of the roots and other parts of plants...(medicine,marked the beginning of chem. process)

philosophical period-dominance of greek philosophies

-used logic and reason in exploring the natural phenomena

-3 phases of matter was discovered

_4 element theory by Aristotle

`fire-hot

`earth- dry

`water-wet

`air-cold

anaxagoras&empedocles assured that all are made up of seeds

-atomic theory of democritus

`the seeds were considered atoms

3.period of alchemy

-by the religious mysticism of Egypt

-transmutation of common metal into gold

-iatrochemistry

-Robert boyle criticized chemistry

4. phlogiston period

by george ernst stahl

the first great principle in chemistry

5.modern times chemistry

experimentation had been gaining acceptance to the community

Antoine lavoisier-father of modern chemistry