One photo a day until I meet Jonathan Harris meetingjonathanharris@gmail.com

11th March

How many bones do you have in your body?

There is a shop just around the corner from where I live called the Centre Matériel Para Médical. Its huge store-front window proudly displays a bizarre array of medical paraphernalia that you normally don't like to think about: stool trays, crutches, stethoscopes and their ilk. For this reason I used to walk past it without a second thought, but these days I can't help but stop and stare every time I walk past.

Why? Its all because of little film called Powers of 10. Even though this film has been around since 1977, I only saw it for the first time about a year and a half ago. In just over 9 minutes it completely blew me away, effortlessly summarising the entire spectrum of scientific understanding and among other things making me realise that even after 30 years, I still didn't know how many bones I had in my own body.

The film begins with a couple picnicking by the shores of Lake Michigan at the start of a lazy afternoon. The picnic is viewed from above at a distance of 1 meter. Then, every 10 seconds the camera zooms out and moves ten times further away. At 10 seconds, we see the picnic from the height of 10 meters. At 20 seconds we see it from 100 meters, at 30 from 1km and so on. If you have ever played with Google Earth, you know exactly what this looks like. First you type in your address and see your house from above, then you slowly zoom out and see the street, the neighbourhood, the city, the country and finally the entire globe. Its a great ride, and Google Earth does a splendid job, but what I realised from watching Powers of 10, is that Google Earth only tells half of the story.

In the second half of the film, we return to the picnic viewed from a height of 1 meter, but this time every 10 seconds, instead of moving away, we zoom in by 10 times. At 10 seconds we see the picnicker from a distance of 10 cm (his hand fills the entire frame), at 20 seconds from a distance of 1 cm (we see just the skin of his hand). And this continues: 1 millimeter, 100 micros. At 10 micros we are inside the hand of the picnicker and looking at one of his white blood cells. It is also a great trip, but I realised with a shock: we don't get to do this in Google Earth! You might be able to see if you parked your car in the driveway on the day the satellite took the photo, but unfortunately with Google Earth, that's about as far as you can go.

This started me thinking. Surely our insides are just as important as our outsides. I knew where Africa was in relation to America, I even knew where Kansas was in relation to Lake Michigan, but it was highly unlikely that my life might ever depend on this information. When it came to my own body, I knew that I had ten fingers and that was about it. In contrast, knowledge about how my body works could have real consequences for my health and well-being. I'd already let 30 years slip by without knowing if my spleen was on my left side or on my right. We might be able to trade-in for a new car every few years, so leaving detailed knowledge of the engine to the mechanics seems sensible, but with our bodies, we hold onto them for life. I'd rather know sooner than later how many cylinders I was running. I needed to start learning my internal geography, and fast. I soon discovered that the subject I was scratching the surface of is well known as the bane of every medical student's early education: Anatomy.

I started searching on the internet for solutions to my problem. Maybe a "Google Anatomy" already existed: all I would have to do was install it in order to have the most up to date anatomical knowledge for the whole body available at my fingertips. To my discontent I found that anatomy is really still the domain of medical students and professionals. Of course everything you wanted to know was available: Wikipedia pages about the different bones, MRI images of the skull, photos of cross sections through the body, but you had to put it all together yourself. If you wanted 3D models and tools that really let you understand how everything fits together you either needed to shell out big bucks for specialist software or try and weasel your way into the libraries of medical schools. Well, I didn't have much money and when I could find the medical schools, my passing-amateur status rarely got me past the first grumpy librarian.

How many bones did I have in my body? Well, Wikipedia told me the answer, but that wasn't enough. I needed to understand how the hip bone was connected to the thigh bone. I needed to be able to see the skeleton from all different angles, in all different positions. "Aha!" I thought, remembering that there might be another option: the Centre Matériel Para Médical

But my hope was short-lived. I raced around the corner only to stop dead in my tracks and stare forlornly through the shop window, my eyes fixed on the small price tag plastered across the plastic cranium: €480. It was then I realised that the skeletons on display were rather like Coronelli's Globes, that is, very expensive and quite inaccessible. Whereas since Coronelli's time we have made a lot of progress toward the accessibility of geographical information (vive Google Earth!), when it comes to anatomy we are still in the dark ages.

So on days like today, I have to content myself with longing glances through the shop window. I did write to Google begging them to work their world-changing magic on our current body of anatomical knowledge, but I am yet to receive a reply.
As for Powers of 10, its probably a lot cheaper than the plastic skeleton. I don't own a copy yet, but considering the amount this film has influenced me, maybe its time that should I should get one... that and a blue leather suitcase.

The answer by the way is 206.