Wager's experiment

Dit werk maakt onderdeel uit van het onderzoekstraject  Exploded View, zone2source, Amstelpark Amsterdam. 

Exploded View startte in 2018 als een serie van bijeenkomsten en expedities met ecologen, parkmanagers, tuinmannen, beleidsmakers, park gebruikers met het doel  nieuwe perspectieven en visies op het park binnen een hedendaagse stedelijke context te ontwikkelen.

Zie ook 



Professor Mancuso schrijft in zijn boek Plant Revolution in het hoofdstuk 'The sublime art of mimesis' dat de beroemde botanicus Haberlandt in 1905 suggereerde dat planten kunnen waarnemen. De epidermale cellen van bladeren zouden convex zijn net als lenzen en beelden kunnen doorsturen naar onderliggende cellagen. Als bewijs toonde Haberlandt een portret van Francis Darwin (zoon van Charles Darwin) geportretteerd door Professor Wager in 1908.

Ik raakte na het lezen van dat hoofdstuk gefascineerd door de gedachte dat de planten in het Amstelpark beelden zouden kunnen genereren en besloot het onderzoek van Wager te herhalen, met behulp van de epidermale cellen van de planten uit het park.


Omdat ik geen beschrijving kon vinden van Wagers experiment ging ik te rade bij een aantal biologen. Sommigen vonden het onzin, anderen stelden experimenten voor die ik heb uitgevoerd, maar zonder resultaat.

Vervolgens keerde ik de vraag om: Hoe zou Professor Wager in 1907 de beelden die deze theorie zo overweldigend illustreren kunnen hebben gemaakt?


Uiteindelijk is het  (denkt ik) gelukt het experiment van Wager te herhalen.

In de Oranjerie in het Amstelpark werd het resultaat samen met het beeld van Wager en een brief aan Professor Mancuso getoond. De vele exotische planten in de tuin voor de Oranjerie staan in het gelid, klaar om mee te kijken.

Nu het ernaar uitziet dat Professor Mancuso haar brief niet zal beantwoorden heeft Birthe Leemeijer bioloog en schrijver Thijs Goldschmidt benaderd om in zijn plaats een reactie te formuleren.

September 25th, 2019

Dear Professor Mancuso,


In your book The Revolutionary Genius of Plants I read about  the compelling results of professor Wager’s experiment in 1908 on the Plants’ Eye View. I am a visual artist from The Netherlands and was fascinated by your book and this chapter in particular. Your research offers new perspectives on all living things – whether they be plants, animals or people. Reading your book means reconsidering everything I feel familiar with, for example: What are the senses, and how can I define them?


In the chapter titled ‘The Sublime Art of Mimesis’ you write that plants contain a sort of eyesight. You base this conclusion on the work done by the well-known botanist Gottlieb Haberland who, in 1905, suggested plants could observe via their epidermal cells. Epidermal cells are often convex and can function as lenses. This enables them to convey images to their underlying layers of cells.


Around the same time Haberland’s colleague, Professor Wager, conducted photographic experiments using the epidermal cells of various plant types. These experiments resulted in relatively detailed portraits of people and English landscapes which, as you wrote, supported the plausibility that plants could indeed observe.


I became fascinated by these images and began looking for a more detailed description of the Wager’s experiment. Unable to find anything on the Internet, I used the photographs in your book as my point of departure. I then discussed Wager’s experiment with several biologists and ecologists, some of them found the whole thing complete nonsensical, a few even dismissing it entirely. There were, however, a few who believed they understood how Wager conducted his experiment. Following their instructions, I attempted to research the epidermal cells by laying the leaf of a Zamioculcas and later of a Scindapsus Epipremnum onto a lightbox with a diapositive and looking at it through a microscope.

In doing so, the leaf became a medium through which I could perceive the world. Yet even though I succeeded in isolating a few transparent cells, I was ultimately unable to see through the leaf or observe any sort of lens distortion.


Rethinking the portraits and landscapes of Wager you described as being very convincing, I decided maybe the best course of action was to reverse the experiment: How was Wager able to take photographs that so perfectly supported this theory?


Once again, I turned to one of the four photographs included in your book. More specifically, the black and white portrait of Francis Darwin, Charles Darwin’s son. I looked at the portrait as I had observed the epidermal cells of the leaf – through a microscope, arranged in exactly the same way. Wager’s photograph seems to say: “Every cell observes its own portrait.”


Using this arrangement, I then poked holes into the aluminum foil of my pinhole camera and took a self-portrait. And I saw the exact same composed photograph as the one Wager took.


This makes me believe I succeeded in mimicking Wager’s experiment. If so, then Wager didn’t use epidermal leaf cells to produce photographs of recognizable landscapes and portraits.

Perhaps this was an initial step in a process of identification? By creating photographs that were both familiar and resembled the way human being see the world, Wager was able to arrest the public’s attention – and even their admiration – at the Dublin conference. Was he hoping to increase his odds of a new research project? Whatever the answer is, he certainly got the attention he was looking for. In response to his photographs, in 1908 the New York Times informed its readers that: “Plants have eyes.”


The reason I am writing you today is that I am curious about your opinion on this. Do you think Wager manipulated the photographs to support this theory? Or did he use another method to create the images? Have you had the opportunity to research the original photographs? And, to your knowledge, are there any existing notes that outline his working methods?


I look forward to hearing from you. Attached is a copy of my interpretation of Wager’s experiment. 


With kind regards.


Birthe Leemeijer. Haarlem, the Netherlands

Het portret van  Francis Darwin  dat Wager maakte in 1909

Boven: Oppervlaktecellen van de Scindapsus Epipremnum

Onder: De resultaten van mijn versie van het experiment