The color of life on our planet is green, because green chlorophyll molecules in plants, which form the basis of all life and convert the energy of incident sunlight into materials from which living things are built. One can only be surprised that in the past centuries people were almost not interested in the mechanism of this energy conversion - the process that we now call photosynthesis. It so happened that the patterns of movement of planets and stars became clear to people long before they had the slightest idea about the role of grass under their feet.
The first serious study of the mechanism of plant growth was carried out by the Flemish aristocrat Jan Baptist Van Helmont. Before planting a tree in a pot, he weighed the earth in it. For several years, Van Helmont watered the tree, and then weighed the tree and earth again and found that the weight of the tree increased by 74 kg, while the weight of the soil decreased by about one hundred grams. It became clear that the soil is not a source of material for building a growing tree.
In fact, Van Helmont drew the wrong conclusion from his discovery - he claimed that the extra weight came from water. It was two centuries before the idea that the carbon in wood is formed by the conversion of atmospheric carbon dioxide, and another century before the molecular mechanism of photosynthesis was understood. Nevertheless, Van Helmont left no one in doubt that the material we call biomass does not come from the soil, but from another source, and this discovery later became the basis for our ideas about the role of plants.
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Jan Baptist VAN HELMONT. Jan Baptista Van Helmont, 1579-1644
Flemish physician and chemist. Born in Brussels into an aristocratic family. He studied medicine and chemistry at the Catholic University of Louvain, but did not receive a degree, but took up his own research. He first used the word "gas" to describe the state of matter and identified four types of gases - carbon monoxide (carbon monoxide), carbon dioxide (carbon dioxide), nitrous oxide (laughing gas) and methane known to us today. At the time of Van Helmont, chemistry was a young and rapidly developing science, in which the influence of alchemy was still strongly felt. Although he did not have immeasurable respect for the ancient teachings considered inviolable, he still believed in the Philosopher's Stone. However, his experience with growing willow trees shows that Van Helmont understood the value of the experiment. And once he even came into conflict with the church,questioning the popular belief that a wound can be healed by healing the weapon that inflicted it.