It’s all about plants this time and the chemical process that’s been a frequent mainstay in spelling bees and quizzes out there, that is, photosynthesis. Not just about the process, but the Dutch-born chemist who discovered photosynthesis.

Photosynthesis is the process in plants and also in other organisms that convert light energy sources into chemical energy, which provides compounds utilized to become “food” or fuel the activities of organisms.

Jan Ingenhousz

It was 18th century’s Jan Ingenhousz who discovered the process the moment he started experimenting with plants underwater. He was also the person behind the phenomenon of how metals conduct heat. As a physician, he helped provide treatment for an Austrian royal family during the outbreak of smallpox and was also a royal doctor. You’ll also learn more about his family.

Jan Ingenhousz was born on December 8, 1730, in Breda, Netherlands. If you happen to be in that corner of the world and want to know where Breda is, don’t bother. The city is known nowadays as the Southern Netherlands.

Born December 8th in the Netherlands

Ingenhousz was born on December 8, 1730 in Netherlands’ southern city and municipality, Breda. Today, the city is more known to be Southern Netherlands.

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Enrolled in Medicine at age 16

Science is his passion. Unlike many students of Medicine these days, who usually begin with the studies after a pre-med course, Ingenhousz started studying the field at only 16 years old. He enrolled at the University of Leuven in Belgium and successfully received M.D. in the 1750s.

He took his first job as their hometown's doctor

Many fresh graduates today will also work at corporations or multinational firms or even travel the world after college. Not for Ingenhousz. After getting his medical degree, he decided to work as a doctor in his hometown, Breda.


Interested with electricity

He was particularly interested in electricity, taking inspiration from another famous scientist of his time, Pieter van Musschenbroek. It all began when he first heard Pieter speak at the University of Leiden where he studied medicine.

Smallpox vaccine

He was considered a royal family doctor, especially when he helped treat King George III and his family, saving them from the smallpox epidemic that took the community by storm. He also gave the vaccine to about 700 Austrian villages.

A royal family doctor

The royal family heard about the success of the vaccinations, and Ingenhousz was named a doctor for The Royal Family of Austria. During this stint, he also saved the life of King Kaiser Leopold II, giving him the smallpox vaccine.

Elected into the "Royal Society"

His contributions to the fields of medical science, math, and engineering led him into being elected into the Fellow of the Royal Society in the 18th century. This was an award given to those in the field by the Royal Society of London.

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The advent of photosynthesis

People first heard of the concept of photosynthesis after he discovered this process where sunlight absorbs carbon dioxide in plants, releasing this into oxygen that fuels these plants for their activities.

Plants underwater

When plants are put underwater, they will form light bubbles. This was during the early stages of the experiment. This remarkable discovery heralded a profound interest in how plants interact with their surroundings.

Joseph Priestly and his oxygen

The same laboratory where scientist Joseph Priestly discovered Oxygen was where Ingenhousz discovered photosynthesis. Science flows in a spectrum, you’ll never know what serendipitous moment can come at you. The experiment into the discovery of photosynthesis also revealed how the plants’ green parts inhaled carbon and released oxygen in the morning while the sun is up.

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Wrote a book of experiments

With this achievement, he also was able to become an author writing a book titled, “Experiments upon Vegetables—Discovering Their Great Power of Purifying the Common Air in the Sunshine and of Injuring It in the Shade and at Night.”

Silver, the best metal for heat conduction

Because electricity is also one of his fortes, this scientist also experimented with metals by dipping them in wax and seeing how much of the metal melted off. This experiment led to the discovery that silver was a great choice when you want to have a metal conducting heat. Lead was the least favorable option.

Did he also discover chlorophyll?

DC Comics Batman’s Poison Ivy will be flattered since she usually talks about chlorophyll in the story. Did Ingenhousz also discover chlorophyll? Yes. They refer to the green parts of the plants that helped through the photosynthesis process.

He's a follower of Benjamin Franklin and his works

If there’s another scientist who he admired, it would be Benjamin Franklin. They also shared ideas with each other.

History of Sorts

The "Brownian Motion"

You’ve heard this one time or another, but don’t try to recall unless you are a student of science and practicing the field. It was also him who discovered the way random movement of particles suspended in a fluid, either liquid or gas, is from interacting with quick atoms or molecules in the liquid or gas.


His scientific work wasn’t without controversy. The Brownian Motion is credited to Robert Brown, but many critics say Ingenhousz’s experiments with gas and fire led to the scientific process.

History and Biography

Fellow scientists

His works in botany won’t be successful without collaborations from Christiaan Huygens and Heike Kamerlingh Onnes, his fellow scientists.


Ingenhousz had one older brother, Ludovicus. He took a different career path from the scientist and went on to study apothecary. He married Agatha Maria Jacquin in 1775 while he was in Vienna. However, they did not bear any children. History does not reveal many details about his parents, known to be Arnoldus Ingenhousz and Maria Ingenhousz. They gave him a good education.

His legacy lives on

Ingenhousz died on September 7, 1799 in England. He was suffering from an illness several months before his death. He would be more than 200 years old today, and his legacy will live on, more so in those people part of the scientific community.