Different Kinds of Air

A man, like  mouse, should have more than one avenue of escapeA man, like a mouse, should have more than one avenue of escape
Joris Hoefnagel (1542 – 1604)

                    Observations on Different Kinds of Air
. . . . I flatter myself that I have accidentally hit upon a method of restoring air which has been injured by the burning of candles, and that I have discovered at least one of the restoratives which nature employs for this purpose. It is vegetation. In what manner this process in nature operates, to produce so remarkable an effect, I do not pretend to have discovered; but a number of facts declare in favour of this hypothesis…
One might have imagined that, since common air is necessary to vegetable, as well as to animal life, both plants and animal had affected it in the same manner, and I own that I had that expectation, when I first put a sprig of mint into a glass-jar, standing inverted in a vessel of water; but when it had continued growing there for some months, I found that the air would neither extinguish a candle, nor was it at all inconvenient to a mouse, which I put into it.
…Accordingly, on the 17th of August 1771, I put a sprig of mint into a quantity of air, in which a wax candle had burned out, and found that, on the 27th of the same month, another candle burned perfectly well in it. This experiment I repeated, without least variation in the event, not less than eight or ten times in the remainder of the summer.
Joseph Priestley (24 March 1733 – 6 February 1804)

In 1771, about the time of the first stirrings of the industrial revolution and its appetite for fossil fuel, an English minister grasped key processes of the natural carbon cycle. In a series of ingenious experiments, Joseph Priestley found that flames and animals’ breath “injure” the air in a sealed jar, making it unwholesome to breathe. But a green sprig of mint, he found, could restore its goodness. Priestley could not name the gases responsible, but we know now that the fire and respiration used up oxygen and gave off carbon dioxide. The mint reversed both processes. Photosynthesis took up the carbon dioxide, converted it into plant tissue, and gave off oxygen as a by-product.

The world is just a bigger jar. Tens of billions of tons of carbon a year pass between land and the atmosphere: given off by living things as they breathe and decay and taken up by green plants, which produce oxygen. A similar traffic in carbon, between marine plants and animals, takes place within the waters of the ocean. And nearly a hundred billion tons of carbon diffuse back and forth between ocean and atmosphere.

In other words:
Alone in a sealed jar, a mouse would die from exhaled CO2. But as Priestley observed in 1771, adding a plant allows the mouse to thrive. In this proof of photosynthesis, the mint absorbed CO2, retained carbon for growth, and released oxygen



The URI to TrackBack this entry is: https://secretgardening.wordpress.com/2015/03/26/different-kinds-of-air/trackback/

RSS feed for comments on this post.

2 CommentsLeave a comment

  1. Wonderful find, Cassie. You really have a genius for it – how beautiful and relevant and critically important – thank you. xxx

    • Thank you.
      Over and over I find how dear knowledge was to those who had to struggle to find ways of understanding. While now that we have sources of information at our actual fingertips—AND all the instructions and instruments with which to test that information and re-prove the facts– a huge proportion of the world prefer to CHOOSE blindness and ignorance.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s