Thin Air comic cover. Black Sabbath album cartoon. Sydney Opera house drawing.
Forest grid drawing. Trees cartoon aerial arrows. A silent construction project is building the world around us. Collectively filling the gaps of Earth's horizontal limits...individually pushing the peaks of Earth's vertical limits.
Low-angle drawing of man under tree. Cartoon tree trunks. Trees engineer mighty columns of wood...and send them skywards in defiance of gravity.
Man reading book under a tree cartoon. Drawing field grass. Countless tonnes of mass hangs in thin air above our heads at all times. But where does this bulk come from? What do trees use to build themselves?
Jean Baptista van Helmont cartoon. Science lab balance scales drawing. This question was asked by Belgian chemist Jean Baptista van Helmont in the 1600s. Conducting one of the first biological experiments, van Helmont carefully weighed 200 pounds (90 kilograms) of dried soil, and then placed it into a pot.
Jean Baptista van Helmont cartoon. Brushing soil from willow tree drawing. Van Helmont then planted a 5 pound willow shoot...and left it to grow, watering when necessary. After five years, Van Helmont dug the plant from the pot and shook off the soil.
Jean Baptista van Helmont cartoon. Van Helmont willow tree drawing. The shoot which first weighed 5 pounds (2 ¼ kilograms) was now a tree weighing 169 pounds (76 ½ kilograms). Van Helmont then dried and weighed the remaining soil.
Soil on balance scales cartoon drawing. Had it lost the 164 pounds of matter which now formed the wood of the willow? No. The soil had lost only 2 ounces (56 grams) of mass. In five years, the willow had burgeoned in size, but where had its mass come from? How had the plant built itself?
Drawing of tree carbon hydrogen oxygen atoms. Carbon dioxide molecules. Hundreds of years of scientific experimentation provided the surprising answer: the wood of plants is made almost entirely from thin air.
Tree bark leaves drawing. Cartoon carbon hydrogen oxygen atoms. Carbon dioxide molecules. Standing tall in the breeze…tree trunks are made of the same stuff that blows past their leaves. A baffling, counterintuitive process which creates structure and mass from little more than a puff of air.
Goanna cartoon. Lace monitor drawing. Lizard in tree. Plants build complex structures to store the energy pulled from the environment...which allows the baton to be passed to the animal kingdom...who use these very same chemical building blocks to construct their own materials of toughness and flexibility.
Rock crab cartoon. Sydney Harbour Bridge reflection in rock pool drawing. Just as trees uptake trace elements to improve their function and form...animals borrow minerals from the environment and crystallise them into the reinforced structures of their bodies. What are the differences between the construction methods of nature and those of human industry?
Urban nature cartoon. Skyscrapers next to bushland drawing.
Office towers and forest cartoon. Aerial view of city trees drawing.
City tree next to building cartoon. Hotel surrounded by trees drawing. Our prized constructions are surrounded by engineering alternatives. Unassuming rivals...built from thin air.
Carbon dioxide molecules diffusion leaves. High angle tree leaf atoms cartoon. Bird's-eye view tree branch drawing. Consider the elegance, consider the efficiency of trees' construction techniques. Self-powered assembly. Built from abundant resources drawn from the local environment. Gradually assembled, yet fully functional at all stages of growth.
High angle skyscraper construction cartoon. Bird's-eye office tower cranes drawing. Open cut mines landscape grid. Consider the crudeness, consider the waste of humanity's construction techniques. The fossil fuels burnt to power the process. The manhandling needed to wrangle construction materials into place.
High angle skyscraper construction cartoon. Bird's-eye office tower cranes drawing. Open cut mines landscape grid. The rare and exotic materials used to build with. The enormous distances resources are carried to the construction site.
Cartoon blimp above Sydney Harbour Bridge. Lizard climbing tree drawing. Comparing the two processes shows nature trumping human industry hands-down for efficiency and resourcefulness. But comparing the products of the two construction methods reveals no clear 'winner'. Human ingenuity has created achievements which had never before been produced by nature. And yet nature has its own showroom of technologies which we are far from understanding or duplicating.
Hermit crab cartoon. Sydney Opera House drawing. We should be proud of our amazing successes...but we should also be aware of our shortcomings...and be willing to learn from others.
Bird in tree branch near Sydney Opera House cartoon. Surprised man Sydney Harbour drawing. Sharing the same planet, the same universal laws, humans have the opportunity to study the fruits of a 3.8 billion year old invention factory.
Bird flying away near Sydney Opera House cartoon. Man thought bubble jumbo jet aeroplane drawing. Nature alerts us to what is possible. What works. Giving us inspiration to try things for ourselves.
Sydney Harbour panorama drawing. Sydney Harbour Bridge cartoon. Side-by-side, the two construction techniques offer a stark contrast.
Sydney Harbour panorama drawing. Sydney Opera House cartoon. All of this was created by pulling matter from the Earth.
Australian bushland scene drawing. Eucalyptus trees cartoon. Gum tree Bearded Dragon lizard comic.
Australian bushland scene drawing. Eucalyptus trees cartoon. Gum tree Kookaburra bird comic. All of this was created by pulling matter from thin air.
Sydney Botanical Gardens gum tree parkland drawing. Sydney Harbour Bridge and Sydney Opera House behind eucalyptus trees cartoon. The prototype exists, the prototype works.
Sydney Botanical Gardens gum tree parkland drawing. Sydney Harbour Bridge and Sydney Opera House behind eucalyptus trees cartoon. Can our future be made from thin air?

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Read some reflections and insights into the Thin Air comic and the way trees build themselves in the blog section of this website.

Support the artist, and buy a $2 PDF of Thin Air.

Thin Air is also available in these languages:

Čeština (cs)


Ελληνικά (el)


Português brasileiro (pt-BR)


中文 (zh)

(Email me to join my volunteer translation / proofreading team!)

If you enjoyed Thin Air, try reading this similar comic:
Type III comic by Stuart McMillen.
What does the Mount St. Helens ecosystem have in common with the human industrial system?

Or for something completely different:
St Matthew Island by Stuart McMillen
What happens when you introduce 29 reindeer to an isolated island of untouched natural resources?
Peak Oil by Stuart McMillen
Roughly half of the world’s entire oil supply is gone; half is left. How will our society choose to use the oil that remains?
  1. Lily Larson says:

    Super helpful with my science, actually. Just ran across one of your images on a Google search, and read the comic. Very helpful! Thanks! And you other things look very interesting , too!

  2. Bill Safstrom says:

    Your cartoons are great. I noticed four of them that are translated into Spanish. Do you have more in Spanish? I guess the Van Helmont cartoon is new. When will it be translated into Spanish?

  3. Pingback: Thin Air | Beautiful New Story

  4. Victor says:

    Thank you so much for these comics. They are wonderful visual representations that I use to teach Life Science and Biology, while making students and people in general think differently about the world around them.

  5. Tesia Bird says:

    This is beautiful and so true & everyone should have a copy of this to show the world and to show there kids and then show there grandkids. Thank you!

  6. Sue Boudreau says:

    Lovely resource for inquiry science curriculum I’ll be using with our 300 7th graders in Orinda, California. Thank you so much. Sue Boudreau

  7. Michael says:

    I find your work very inspiring. Never stop creating!

  8. Pingback: The Great Disruption (moving to Canberra) - Stuart McMillen blog

  9. John Warren says:

    This is fascinating to see this perspective in the context of the book I am reading, “The Tree” by Colin Tudge. Thanks, with much appreciation of the world that they make possible to be creative in.

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  11. Pingback: Comic connecting nature to building, reminded me of Community Rebuilds | Lauren Builds

  12. Lauren says:

    This could serve as an incredible introduction to introduction into natural home building. Will send to the executive director of Community Rebuilds ( and other straw bale and natural builders. Thank you!

  13. Pingback: Thin Air reflections - Stuart McMillen blog

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  15. Paul & Deb McMillen says:

    Once again your attention to detail leaves us breathless. Congratulations on yet another thoughtful piece.

  16. Paul Dutch says:

    Interesting cartoon, but what it neglected to mention is that the tree needs water also to grow, not just air..
    But in essence this is a world view that should not stop at the imaginary barrier between Nature and the Human world. All the world “things” are made from the same building blocks if you go to a small enough scale. The tree is built from the same stuff as the skyscraper.
    But I like the way the cartoonist pushes a more organic way of producing and building.
    It is certainly the way that the world will go I think.

    • Paul Dutch says:

      It does mention the water element, but doesn’t emphasize it greatly..

  17. Django says:

    Thank you for this insight in the world around me *us ! (: ^.^

  18. Pingback: Thin Air – Stuart McMillen comics « John Cameron's Blog

  19. Alex Noriega says:

    Amazing! I love it

  20. Leon says:

    Amazing Comic, as usual.
    One quick question, did you take your inspiration for this from one of Feynman’s videos on the trees carbon coming from the air’s carbon?

    Don’t stop doing this man, you are just tooooo good.

  21. Sam says:

    Yes – glad you mentioned that ‘Nature’ has a 3.8 billion year start on us in the field of ‘design’ and construction…. 😉 …but we’re getting there. Nice dream though -the ability to construct what we need for our civilisation from thin air…. Thanks again Stuart -lovely images, really well drawn!! – love the way you draw trees! You somehow manage to capture their majesty…

  22. Pingback: Stuart McMillen's Insightful Cartoon Uncovers the Engineering Secrets Hidden In Trees | Inhabitat - Sustainable Design Innovation, Eco Architecture, Green Building

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