We all need oxygen to survive.  Oxygen-rich air gets into our bodies via our lungs.  Unlike other passageways in our body, the muscular wall of the trachea is braced.  So, the connection into our lungs always stays open - except when swallowing temporarily covers the opening.

From the trachea, a system of bronchial tubes spreads out like an inverted tree.  Thinner and thinner branches end in clusters of air sacks, that hang like bunches of grapes.

In our lungs there are over seven hundred and fifty million of these tiny air sacks, known as alveoli.  These sacks have a thin membrane, comprised of a fine network of capillaries.  Across this membrane, air and blood exchange oxygen and carbon dioxide gases.

The lungs have a separate loop of blood vessels leading to and from the heart.  As these blood vessels divide in the lung, into a network of capillaries, their surface area greatly increases.  In total, this vast surface of thread-like capillaries is about fifty times the area of the skin.

In this way, a huge film of blood is spread to a depth of only one blood cell.  In the alveoli, the haemoglobin of the red blood cells takes on massive amounts of oxygen, which circulates throughout the body delivering oxygen to all our cells.

So next time you feel your lungs expand, be grateful for that magnificent breathing machine that keeps you alive.

MOVING BEYOND MATTER
by Christopher Shennan

How can something so basic to our survival, like breathing, be so unconscious an action that we hardly ever think about it?

Only in extraordinary circumstances, like being trapped in an airless hull under the sea, or perhaps when asthma afflicts us, does the need to breathe become of absorbing interest to us.  Or, perhaps the issue of air quality in our industrialized society may turn our thoughts in that direction.  But in general, though, most of us go through entire days or weeks without thinking about our need to breathe.  We do it unconsciously and undramatically, hardly aware we are doing it at all.  And what a blessing that is.  It would be very distracting, and inconvenient, to have to think about every breath we take.

There are other things, however, we should train ourselves to be constantly aware of, like the beauty of a sunset, the love of family, or the ability to earn a living.  Such awareness will add an element of thanksgiving to our lives.  It will rescue us from the glum disease of a complaining spirit.

It is quite natural to be on automatic pilot when it comes to breathing.  But we should never take other blessings of life for granted.

How long has it been since you were thankful for the air you breathe, or the daily benefits of everyday life?  How long has it been since you thought of yourself as more than mere body and mind with a personality? Have you remembered to give some attention to the spiritual dimension of your life?

We don't have to give a great deal of thought to breathing to stay alive.  To have a wholly satisfying life, however, it is vital we realize humans are endowed with soul and spirit, as well as body and mind.  Even if we don't care much for religion, most of us (when cornered) will admit to an empty space in our lives that  - well, it's just hard to fill.

It may not be a bad idea to investigate the possibility that the solution to our emptiness is, in fact, spiritual.