Ask HN: How did people think plants worked before photosynthesis was discovered? - hammock
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serf
The ancient Greeks thought that plants gained mass by stealing it from the
soil. Not that wrong.

Later on a Belgian scientist (Jan Baptista van Helmont) thought that he had
discovered that plants gained nutrients from water, using an experiment that
weighed a plant over time versus the weight of the soil over time.

Even later on a British scientist (Joseph Priestly) discovered gas exchange
from plants by measuring how much time had elapsed before a flame could be re-
ignited after allowing the flame to deprive the experiment area of oxygen.

Even more later on a Dutch scientist (Jan Ingenhousz) correlated light with
the process of gas exchange, then met up with the previous British scientist
(Joseph Priestly) and discovered that the gas output from the process was
oxygen.

Read about it all here :
[https://www.bbc.co.uk/bitesize/guides/zq8s2nb/revision/4](https://www.bbc.co.uk/bitesize/guides/zq8s2nb/revision/4)

~~~
sova
Related Explanation/Discovery : "But if you ask, where the substance comes
from... the trees come out of the air?!" -Richard Feynman
[https://www.youtube.com/watch?v=N1pIYI5JQLE&feature=youtu.be...](https://www.youtube.com/watch?v=N1pIYI5JQLE&feature=youtu.be&t=133)

