Monday, December 26, 2011

Valley of the Cable Ties: the material culture of the contemporary past

Back in November, me and my intrepid group of graduate students paid a visit to the former Orroral Valley Tracking Station in the ACT.

In the 1990s, what remained of the above-ground structures was demolished, leaving only the concrete footings of numerous buildings and antennas.  Near the entrance to the facility, now used by tourists, hikers and other visitors, the grass is cut and the gardens sort of maintained. Deeper into the site, tall weeds and grasses are more prevalent and are invading the antenna footprints. 

In general, surface visibility is on the low side, and as you walk about, there's not much evidence of past human activities apart from the big stuff.  No obvious artefact scatters; no personal objects; no bits of antenna support lying discarded.  Occasionally there's a bit of recent rubbish near the picnic/parking area. The Maralinga nuclear test sites are littered with lovely radioactive garbage, despite three remediation campaigns; by comparison, Orroral has been cleaned up and maintained in a well-ordered fashion.

But I wasn't so sure this tidy surface would yield nothing to the eagle eye of the archaeologist.  On my last visit, we found an old scrubbing brush lying outside the canteen building, the sturdy bristly kind with a wooden back, as used in a million domestic and industrial kitchens across the land.  I was very keen to do a pedestrian transect survey of the entire site to see what else we could find relating to the tracking station period, and what its spatial distribution might tell us.  I imagined we might be able to knock the whole site over in a day with 10 people.

You'll already have guessed that my expectations were confounded.

We started at what I thought would be the easiest part of the site, below the main 26 m antenna, which is fairly thickly grassed with few weeds. This was possibly the narrowest section of the main site, defined by fences, and with no buildings to confuse things.  I really didn't think there would be much there; I thought it would be a nice, quick demonstration of the principles of surface survey.

The team walked 5 m apart, slowly observing the ground within their swath of vision, and placed a pin flag at every location where they saw human material or animal scratchings/burrows.  The latter was so that I could get an idea of how disturbed the surface was.  We had 100 pin flags (these are spikes of metal with a coloured plastic tag on top) and I thought these would last us a good while.  The line would move from one boundary fence to the next in formation, flagging everything of interest, and then we would look back and see how material was distributed by the density of the flags.  Then, in small groups, the team would fully record each artefact or trace, including its coordinates, material, dimensions, shape, colour, likely function if known, etc etc, removing the flag as each location was completed (and leaving the artefact in situ). We'd then move on to the next 50 m traverse.

From L to R: Joan, Rob and Susan in their 5 m transects. (Author's photograph)
Well. Once you start looking ...... the 100 pin flags were running dangerously low before we had even reached the opposite fence.  There was stuff everywhere, despite the low visibility as you see in the image above.  I was amazed, and so were the students. There were bits of concrete, star pickets, bricks, lead, tin cans, insulation, wire, nails, leather, cable trenches (some of the rabbit scratches turned out not to be, once you examined them closely), metal steps, pipes, and much more.  When we made a list of all the observed artefact materials or types, there were over 30. 

Southwest from the antenna footing, showing the location of pin flags. (Author's photograph)
This was all great, obviously, although now it was clear that we would be lucky to get through half of this small area in a day, let alone the whole site.  But the best was yet to come. 

In the picture below, you see an erosion scar with a high density of artefacts, as evidenced by the density of pin flags.
Artefact density in the erosion scar (with Lance, Tom and Steve). (Author's photograph)
 Obviously visibility was highest in this exposed area, and so we would expect a higher density of artefacts than the surrounding grassed areas. Some, at least, were being washed down or out of the slope; the presence of a small culvert under a path nearby attested to the movement of water through this area.  But it was the content of this artefact scatter which was the biggest eye-opener.

Pretty soon, as the teams moved systematically through recording the artefacts, we became aware that there were quite a few cable ties present; so many that some people suggested that there was no need to individually photograph and measure every one.  Tempting though that thought was .... I stuck to my guns. This was the methodology and we were going to follow it to the letter.! There was a little grumbling. Why record the same features on so many of them, when they were all identical? What would we learn?

Again, once you start looking...... the first thing to note was that these were used cable ties, not new ones. They had been removed from something.  One team observed a tie that had been torn apart, as the edges were jagged.  I then instructed everyone to pay attention to the ends and record their state.  Three variations then became evident: some had been torn, some cut, and some melted.  This tiny observation on a discarded piece of plastic translated into a decision and an action taken by a real person in carrying out a task.

From this starting point, as we compared the cable ties that occurred across the erosion scar, other variations emerged.  There were different colours: black, white, translucent. There were different lengths and different widths, from the very skinny and short to the very long and thick.   The length, and thickness could be an indication of the diameter and load that the tie was used for.  Some had had the loose ends trimmed off. Some had patent numbers on them, or manufacturer's labels. Some were lying flat on the surface; others were actively eroding out, standing upright in a layer of silt.

I was delighted. This ubiquitous, seemingly simple object was raising all kinds of questions about how and why the cable ties had been used. How did they get there? Were they associated with the tracking station?  What date were they?  When, exactly, had cable ties been invented?  None of us knew.  We all knew what they were, but we knew absolutely nothing else about this very modern artefact type.

By this time someone had decided to start substituting cable ties in film names - such a shame that we had no mobile coverage or there would have been a great Twitter hashtag in it - #cabletiemovies - such gems as The Texas Cable Tie Massacre (Jonathan) and The Valley of the Cable Ties (Susan) raised much hilarity. (My own effort:  The Cable Tie, being a film starring Jim Carrey). But I could tell that despite their ostensible skepticism, everyone was getting caught up in the cable tie story.  I decided to have a brainstorm session.

First we considered when cable ties were invented.  (We couldn't just look this up; out here our phones didn't have reception. The whole point of locating a satellite tracking station in this valley was its radio quietness).  Like many things that people assume are very modern, I thought perhaps cable ties were quite old, 1850s or something like that.  Others thought they might be 1950s or 1960s.  Rob pointed out that an omega-shaped clip used to be used to secure pipes and cables to structures. Another question was mass production.  While the technology may be old, their accessibility may be recent.  Early cable ties, he proposed, may have been expensive, and those at Orroral may have all been imported from the US.  Perhaps they were not throw-away technology in the early days.

What were so many cable ties doing near the main antenna?  Were they associated with the dismantling of the antenna?  Steve imagined a bunch of blokes climbing all over the structure cutting the ties off, as they took it apart to be transported to Tasmania (where it became part of the Mt Pleasant Observatory). The prevailing wind over the last couple of days had been from the north east; if it had been so in the 1980s, then perhaps the cable ties were just whisked off to the ground, scattering over the grass to the south west of the antenna. It was a plausible theory.

Joan, however, drew our attention to the huge numbers of kangaroos throughout the area (they were all over the site - and of course Canberra is renowned for being the one city in Australia where you can actually see a mob of roos hopping through the streets!).  What if the national park had culling programs? The cable ties might be used to tie the feet of the corpse together so it could be transported. (Sorry to raise this gruesome topic).

It was Tom who had first noticed the melted ends of some cable ties, and he told us that cable ties were commonly used by hikers and backpackers to secure their baggage.  They would then burn them off with cigarette lighters.  Just to the right of us was a path that already we had seen several groups of outward bounders travel down to the other end of the valley.  These groups of high school students were camping up near the old canteen, and every day two different groups would walk right past our erosion site.  However, as someone else pointed out, they were just walking through: you would expect to see old cable ties more at camping locations.

So we had some reasonable hypotheses here, and would need to do some research to discriminate between them.  It was no good making assumptions that antenna cables = cable ties.  We had also to consider that many may have washed down from further upslope, and may not have blown down from the main antenna at all.  A key piece of evidence was clearly going to be the distribution of cable ties over the whole site.  What features were they most associated with?

We didn't get a chance to do any more transects, but we did investigate the 9 m antenna footing with a group of home school children who came out to visit us.  Around the footing, we found a sparse scatter of cable ties. So clearly they were present elsewhere at the site, although the association with the actual antennas was not certain since we had only looked at two of them.

Later, we had a wonderful morning out at the Canberra Deep Space Communications Complex with Glen Nagle.  Towards the end of his talk to us, he asked if anyone had any questions.  I saw a few significant glances exchanged between the students.  Hello, I thought.  I was pretty sure they wanted someone to ask about cable ties - but no-one wanted to be the patsy!  Joan, though, was made of sterner stuff.  The glances coalesced into consensus and Joan gave a wry smile before asking Glen how common cable ties were in the construction and operation of the antennas at Tidbinbilla.

Glen Nagle tells us about the history of the Tidbinbilla tracking station. (Author's photograph)
Now, I thought, my moment of vindication.  I was a little disconcerted when Glen roared with laughter! But when he recovered, he had some interesting insights.  On the main 70 m dish at Tid, he said, there would be 1000s of cable ties.  They were in fact an OH & S issue, and one of their engineers was meticulous about enforcing this - if the ends are not cut off, then they can easily take an eye out, as had happened to one unfortunate employee.  So we had another factor to consider in our assessment of the cable ties from Orroral. Then he sent his off-sider to the office to get us all a genuine Tidbinbilla cable tie!  I was in seventh heaven.

It wasn't until Susan got to the airport and logged in that we found out when the plastic mass-produced cable tie was invented - 1958, as it happens, by the US company Thomas & Betts, to use for securing wire harnesses in aircraft.

Of all the things I expected to get out of using a very "traditional" archaeological technique on a space site, the discovery of cable ties was certainly not amongst them. My initial field seasons to Orroral had led to me realise the importance of cables, as opposed to the fancy, obvious stuff like antennas (and don't get me wrong, I'm still completely in love with antennas), but it took the application of the archaeological eye and a systematic approach to recording to tease out the implications.  It's so obvious when you think about it.  Glen, once he had recovered from his hilarity, agreed: there is another story to be told about technology through cable ties, and part of that story is their dissemination throughout contemporary culture, their adaptation to all kinds of uses, leading to their virtual invisibility.

As far as I'm concerned, cable ties are the quintessential artefact representing the potential of the archaeology of the contemporary past.

I will make them visible again.

A few weeks later, I'm having dinner with the president of the Australian Archaeological Association, my esteemed colleague Dr Lynley Wallis, in a regional Queensland town on a Sunday night.  There's not many places open and we have to settle for a cafe which is also hosting a Christian a capella group.  "Lynley", I say, "I have to tell you about my recent discovery concerning cable ties!"  "Keep your voice down", she replies.  "There's a lot of elderly Christians about who may not be comfortable overhearing such a conversation".  I'm nonplussed.  Why would anyone care?  Then I realise: she assumes I am about to impart some revelation concerning kinky sex.  And this, sadly, is the immediate association that many people have with cable ties:  restraint, whether in the boudoir, down at the police station, or in a hostage situation.

Saturday, December 10, 2011

Happy Christmas from Dr Space Junk

I'm organised this year!  This collage is from my Facebook status updates, those (mostly) with a space theme, of course.

If the text is too small to read click on the picture to get a larger version.  That's if you really want to know my innermost thoughts.